LM3643 具有 1.5A 高侧电流源的同步升压双 LED 闪光灯驱动器
- ZHCSCQ7A August 2014 – November 2014 LM3643
  
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LM3643 具有 1.5A 高侧电流源的同步升压双 LED 闪光灯驱动器

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1 特性

工作期间允许的总 LED 电流为 1.5A
(I_LED1 + I_LED2 = 1.5A)
两个可独立编程的 LED 电流源
准确的可编程 LED 电流范围为 1.4mA 到 1.5A
优化了低电池电量条件下的闪存 LED 电流（输入电压闪存监控器 (IVFM)）
手电筒模式（100mA 时）和闪存模式（1A 至 1.5A 时）的效率超过 85%
支持阴极接地 LED 操作，改进了热管理
小型解决方案尺寸：< 16mm²
硬件选通使能 (STROBE)
射频功率放大器脉冲事件的同步输入 (TX)
硬件火炬使能 (TORCH/TEMP)
远程 NTC 监控 (TORCH/TEMP)
400kHz I²C 兼容接口
- LM3643（I²C 地址 = 0x63）
- LM3643A（I²C 地址 = 0x67）

2 应用

可拍照手机白色 LED 闪光灯

3 说明

LM3643 是一款双 LED 闪存驱动器，能够以较小的解决方案尺寸提供高度可调节性。LM3643 采用 2MHz 或 4MHz 固定频率同步升压转换器为 1.5A 恒流 LED 源供电。LM3643 升压闪存驱动器可提供的总 LED 电流为 1.5A (I_LED1 + I_LED2)。两个 128 级电流源可灵活调整 LED1 与 LED2 之间的电流比，每个驱动器最多能够提供 1.5A 电流（例如：I_LED1 = 1.5A 和 I_LED2 = 0FF；I_LED1 = 0FF 和 I_LED2 = 1.5A；或者电流低于 1.5A 的电流配置：I_LED1 = 950mA，I_LED2 = 250mA）。自适应调节方法可确保电流源保持可调节状态，并且最大限度地提升效率。

LM3643 的功能由兼容 I²C 的接口控制。这些功能包括：硬件闪光灯和硬件手电筒引脚（STROBE 和 TORCH/TEMP）、TX 中断和负温度系数 (NTC) 热敏电阻监视器。器件在每个输出引脚均提供了可独立编程的电流，以便在闪存模式或录像（手电筒）模式条件下驱动 LED。

该器件的开关频率选项为 2MHz 或 4MHz，具备过压保护 (OVP) 和可调节限流功能，因此可采用微型超薄电感和 10μF 陶瓷电容。该器件的工作环境温度范围为 -40°C 至 +85°C。

器件信息⁽¹⁾

器件型号	封装	封装尺寸（最大值）
LM3643	芯片级球状引脚栅格阵列 (DSBGA) (12)	1.69mm x 1.31mm

要了解所有可用封装，请见数据表末尾的可订购产品附录。

简化电路原理图

4 修订历史记录

Changes from * Revision (August 2014) to A Revision

Added 有关 LM3643A 的信息 Go
Changed '011' to '000' - typoGo

5 Device Comparison Table

ORDERING PART NUMBER	I²C ADDRESS
LM3643YFFR	0x63
LM3643AYFFR	0x67

6 Pin Configuration and Functions

YFF Package

12-Pin DSBGA

Pin Functions

PIN		DESCRIPTION
NUMBER	NAME	DESCRIPTION
A1	GND	Input voltage connection. Connect IN to the input supply and bypass to GND with a 10-µF or larger ceramic capacitor.
A2	IN	Serial data input/output in the I²C Mode on LM3643.
A3	SDA	Drain Connection for Internal NMOS and Synchronous PMOS Switches.
B1	SW	Active high hardware flash enable. Drive STROBE high to turn on Flash pulse. Internal pulldown resistor of 300 kΩ between STROBE and GND.
B2	STROBE	Serial clock input for LM3643.
B3	SCL	Step-up DC-DC converter output. Connect a 10-µF ceramic capacitor between this terminal and GND.
C1	OUT	Active high enable pin. High = Standby, Low = Shutdown/Reset. Internal pulldown resistor of 300 kΩ between HWEN and GND.
C2	HWEN	Torch terminal input or threshold detector for NTC temperature sensing and current scale back.
C3	TORCH/TEMP	High-side current source output for flash LED.
D1	LED2	Configurable dual polarity power amplifier synchronization input. Internal pulldown resistor of 300 kΩ between TX and GND.
D2	TX	High-side current source output for flash LED.
D3	LED1

7 Specifications

7.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)⁽¹⁾⁽²⁾

	MIN	MAX	UNIT
IN, SW, OUT, LED1, LED2	−0.3	6	V
SDA, SCL, TX, TORCH/TEMP, HWEN, STROBE	−0.3 to the lesser of (V_IN+0.3) w/ 6 V max		V
Continuous power dissipation⁽³⁾	Internally limited
Junction temperature (T_J-MAX)		150	°C
Maximum lead temperature (soldering)	See⁽⁴⁾
Storage temperature, T_stg	−65	150	°C

(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(2) All voltages are with respect to the potential at the GND terminal.

(3) Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at T_J = 150°C (typical) and disengages at T_J = 135°C (typical). Thermal shutdown is ensured by design.

(4) For detailed soldering specifications and information, please refer to TI Application Note DSBGA Wafer Level Chip Scale Package (SNVA009).

7.2 ESD Ratings

			VALUE	UNIT
V_(ESD)	Electrostatic discharge	Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001⁽¹⁾	±2500	V
V_(ESD)	Electrostatic discharge	Charged-device model (CDM), per JEDEC specification JESD22-C101⁽²⁾	±1500	V

(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.

(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.

7.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)⁽¹⁾⁽²⁾

	MIN	MAX	UNIT
V_IN	2.5	5.5	V
Junction temperature (T_J)	−40	125	°C
Ambient temperature (T_A)⁽³⁾	−40	85	°C

(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

(2) All voltages are with respect to the potential at the GND terminal.

(3) In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may have to be derated. Maximum ambient temperature (T_A-MAX) is dependent on the maximum operating junction temperature (T_J-MAX-OP = 125°C), the maximum power dissipation of the device in the application (P_D-MAX), and the junction-to-ambient thermal resistance of the part/package in the application (R_θJA), as given by the following equation: T_A-MAX = T_J-MAX-OP – (R_θJA × P_D-MAX).

7.4 Thermal Information

THERMAL METRIC⁽¹⁾		LM3643	UNIT
		DSBGA
		12 PINS
R_θJA	Junction-to-ambient thermal resistance	90.2	°C/W
R_θJC(top)	Junction-to-case (top) thermal resistance	0.5
R_θJB	Junction-to-board thermal resistance	40.0
ψ_JT	Junction-to-top characterization parameter	3.0
ψ_JB	Junction-to-board characterization parameter	39.2

(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.

7.5 Electrical Characteristics

Typical limits tested at T_A = 25°C. Minimum and maximum limits apply over the full operating ambient temperature range (−40°C ≤ T_A ≤ 85°C). Unless otherwise specified, V_IN = 3.6 V, HWEN = V_IN.⁽¹⁾⁽²⁾

PARAMETER		TEST CONDITIONS		MIN	TYP	MAX	UNIT
CURRENT SOURCE SPECIFICATIONS
I_LED1/2	Current source accuracy	V_OUT = 4 V, flash code = 0x7F = 1.5 A flash		–7%	1.5	7%	A
I_LED1/2	Current source accuracy	V_OUT = 4 V, torch code = 0x3F = 89.3 mA torch or		–10%	89.3	10%	mA
V_HR	LED1 and LED2 current source regulation voltage	I_LED1/2 = 729 mA	Flash		290		mV
V_HR	LED1 and LED2 current source regulation voltage	I_LED1/2 = 179 mA	Torch		158		mV
V_OVP		ON threshold		4.86	5	5.1	V
V_OVP		OFF threshold		4.75	4.88	4.99	V
STEP-UP DC/DC CONVERTER SPECIFICATIONS
R_PMOS	PMOS switch on-resistance				86		mΩ
R_NMOS	NMOS switch on-resistance				65		mΩ
I_CL	Switch current limit	Reg 0x07, bit[0] = 0		–12%	1.9	12%	A
I_CL	Switch current limit	Reg 0x07, bit[0] = 1		–12%	2.8	12%	A
UVLO	Undervoltage lockout threshold	Falling V_IN		–2%	2.5	2%	V
V_TRIP	NTC comparator trip threshold	Reg 0x09, bits[3:1] = '100'		–5%	0.6	5%	V
I_NTC	NTC current			–6%	50	6%	µA
V_IVFM	Input voltage flash monitor trip threshold	Reg 0x02, bits[5:3] = '000'		–3%	2.9	3%	V
I_Q	Quiescent supply current	Device not switching pass mode			0.3	0.75	mA
I_SD	Shutdown supply current	Device disabled, HWEN = 0 V 2.5 V ≤ V_IN ≤ 5.5 V			0.1	4	µA
I_SB	Standby supply current	Device disabled, HWEN = 1.8 V 2.5 V ≤ V_IN ≤ 5.5 V			2.5	10	µA
HWEN, TORCH/TEMP, STROBE, TX VOLTAGE SPECIFICATIONS
V_IL	Input logic low	2.5 V ≤ V_IN ≤ 5.5 V		0		0.4	V
V_IH	Input logic high	2.5 V ≤ V_IN ≤ 5.5 V		1.2		V_IN	V
I²C-COMPATIBLE INTERFACE SPECIFICATIONS (SCL, SDA)
V_IL	Input logic low	2.5 V ≤ V_IN ≤ 4.2 V		0		0.4	V
V_IH	Input logic high	2.5 V ≤ V_IN ≤ 4.2 V		1.2		V_IN	V
V_OL	Output logic low	I_LOAD = 3 mA				400	mV

(1) Minimum (Min) and Maximum (Max) limits are specified by design, test, or statistical analysis. Typical (typ.) numbers are not verified, but do represent the most likely norm. Unless otherwise specified, conditions for typical specifications are: V_IN = 3.6 V and T_A = 25°C.

(2) All voltages are with respect to the potential at the GND pin.

7.6 Timing Requirements

		MIN	UNIT
t₁	SCL clock period	2.4	µs
t₂	Data in set-up time to SCL high	100	ns
t₃	Data out stable After SCL low	0	ns
t₄	SDA low set-up time to SCL Low (start)	100	ns
t₅	SDA high hold time after SCL high (stop)	100	ns

7.7 Switching Characteristics

over operating free-air temperature range (unless otherwise noted)

PARAMETER		TEST CONDITIONS	MIN	TYP	MAX	UNIT
ƒ_SW	Switching frequency	2.5 V ≤ V_IN ≤ 5.5 V	–6%	4	6%	MHz

Figure 1. I²C-Compatible Interface Specifications

7.8 Typical Characteristics

Ambient temperature is 25°C, input voltage is 3.6 V, HWEN = V_IN, C_IN = C_OUT= 2 × 10 µF and L = 1 µH, unless otherwise noted .

Figure 2. LED1 Flash Current vs Brightness Code

Figure 3. LED2 Flash Current vs Brightness Code

Figure 4. LED1 Torch Current vs Brightness Code

Figure 6. LED1 Current vs Input Voltage

Figure 8. LED2 Current vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 2 MHz	Flash

Figure 10. LED1/2 Current vs Input Voltage

I_LED = 1 A	ƒ_SW = 2 MHz	Flash

Figure 12. LED1/2 Current vs Input Voltage

I_LED = 179 mA	ƒ_SW = 2 MHz	Torch

Figure 14. LED Current vs Input Voltage

I_LED = 179 mA	ƒ_SW = 2 MHz	Torch

Figure 16. LED1 and LED2 Current vs Input Voltage

HWEN = VIN	I2C = VIN

Figure 18. Standby Current vs Input Voltage

HWEN = 1.8 V	I2C = 1.8 V

Figure 20. Standby Current vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 4 MHz	V_LED = 4.5 V
I_CL = 1.9 A

Figure 22. Inductor Current Limit vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 4 MHz	V_LED = 4.5 V
I_CL = 2.8 A

Figure 24. Inductor Current Limit vs Input Voltage

Figure 26. 4-MHz Switching Frequency vs Input Voltage

Figure 5. LED2 Torch Current vs Brightness Code

Figure 7. LED1 Current vs Input Voltage

Figure 9. LED2 Current vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 4 MHz	Flash

Figure 11. LED1/2 Current vs Input Voltage

I_LED = 730 mA	ƒ_SW = 2 MHz	Flash

Figure 13. LED1 and LED2 Current vs Input Voltage

I_LED = 179 mA	ƒ_SW = 4 MHz	Torch

Figure 15. LED Current vs Input Voltage

HWEN = 0 V	I2C = 0 V

Figure 17. Shutdown Current vs Input Voltage

HWEN = 1.8 V	I2C = 0 V

Figure 19. Standby Current vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 2 MHz	V_LED = 4.5 V
I_CL = 1.9 A

Figure 21. Inductor Current Limit vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 2 MHz	V_LED = 4.5 V
I_CL = 2.8 A

Figure 23. Inductor Current Limit vs Input Voltage

Figure 25. 2-MHz Switching Frequency vs Input Voltage

8 Detailed Description

8.1 Overview

The LM3643 is a high-power white LED flash driver capable of delivering up to 1.5 A in either of the two parallel LEDs. The total allowed LED current during operation of the LM3643 (I_LED1 + I_LED2) is 1.5 A. The device incorporates a 2-MHz or 4-MHz constant frequency-synchronous current-mode PWM boost converter and dual high-side current sources to regulate the LED current over the 2.5-V to 5.5-V input voltage range.

The LM3643 PWM DC-DC boost converter switches and boosts the output to maintain at least V_HR across each of the current sources (LED1/2). This minimum headroom voltage ensures that both current sources remain in regulation. If the input voltage is above the LED voltage + current source headroom voltage the device does not switch, but turns the PFET on continuously (Pass mode). In Pass mode the difference between (V_IN − I_LED × R_PMOS) and the voltage across the LED is dropped across the current source.

The LM3643 has three logic inputs including a hardware Flash Enable (STROBE), a hardware Torch Enable (TORCH/TEMP, TORCH = default), and a Flash Interrupt input (TX) designed to interrupt the flash pulse during high battery-current conditions. These logic inputs have internal 300-kΩ (typical) pulldown resistors to GND.

Additional features of the LM3643 include an internal comparator for LED thermal sensing via an external NTC thermistor and an input voltage monitor that can reduce the Flash current during low V_IN conditions. It also has a Hardware Enable (HWEN) pin that can be used to reset the state of the device and the registers by pulling the HWEN pin to ground.

Control is done via an I²C-compatible interface. This includes adjustment of the Flash and Torch current levels, changing the Flash Timeout Duration, and changing the switch current limit. Additionally, there are flag and status bits that indicate flash current time-out, LED overtemperature condition, LED failure (open/short), device thermal shutdown, TX interrupt, and V_IN undervoltage conditions.

8.2 Functional Block Diagram

8.3 Feature Description

8.3.1 Flash Mode

In Flash Mode, the LED current sources (LED1/2) provide 128 target current levels from 10.9 mA to 1500 mA. The total allowed LED current during operation is 1.5 A (I_LED1 + I_LED2 = 1.5 A). Once the Flash sequence is activated the current source (LED) ramps up to the programmed Flash current by stepping through all current steps until the programmed current is reached. The headroom in the two current sources can be regulated to provide 10.9 mA to 1.5 A on each of the two output legs. There is an option in the register settings to keep the two currents in the output leg the same.

When the device is enabled in Flash Mode through the Enable Register, all mode bits in the Enable Register are cleared after a flash time-out event.

8.3.2 Torch Mode

In Torch mode, the LED current sources (LED1/2) provide 128 target current levels from 0.977 mA to 179 mA . The Torch currents are adjusted via the LED1 and LED2 LED Torch Brightness Registers. Torch mode is activated by the Enable Register (setting M1, M0 to '10'), or by pulling the TORCH/TEMP pin HIGH when the pin is enabled (Enable Register) and set to Torch Mode. Once the TORCH sequence is activated the active current sources (LED1/2) ramps up to the programmed Torch current by stepping through all current steps until the programmed current is reached. The rate at which the current ramps is determined by the value chosen in the Timing Register.

Torch Mode is not affected by Flash Timeout or by a TX Interrupt event.

8.3.3 IR Mode

In IR Mode, the target LED current is equal to the value stored in the LED1/2 Flash Brightness Registers. When IR mode is enabled (setting M1, M0 to '01'), the boost converter turns on and set the output equal to the input (pass-mode). At this point, toggling the STROBE pin enables and disables the LED1/2 current sources (if enabled). The strobe pin can only be set to be Level sensitive, meaning all timing of the IR pulse is externally controlled. In IR Mode, the current sources do not ramp the LED outputs to the target. The current transitions immediately from off to on and then on to off.

Figure 27. IR Mode with Boost

Figure 28. IR Mode Pass Only

Figure 29. IR Mode Timeout

8.4 Device Functioning Modes

8.4.1 Start-Up (Enabling The Device)

Turn on of the LM3643 Torch and Flash modes can be done through the Enable Register. On start-up, when V_OUT is less than V_IN the internal synchronous PFET turns on as a current source and delivers 200 mA (typical) to the output capacitor. During this time the current source (LED) is off. When the voltage across the output capacitor reaches 2.2 V (typical) the current source turns on. At turnon the current source steps through each FLASH or TORCH level until the target LED current is reached. This gives the device a controlled turnon and limits inrush current from the V_IN supply.

8.4.2 Pass Mode

The LM3643 starts up in Pass Mode and stays there until Boost Mode is needed to maintain regulation. If the voltage difference between V_OUT and V_LED falls below V_HR, the device switches to Boost Mode. In Pass Mode the boost converter does not switch, and the synchronous PFET turns fully on bringing V_OUT up to V_IN − I_LED × R_PMOS. In Pass Mode the inductor current is not limited by the peak current limit.

8.4.3 Power Amplifier Synchronization (TX)

The TX pin is a Power Amplifier Synchronization input. This is designed to reduce the flash LED current and thus limit the battery current during high battery current conditions such as PA transmit events. When the LM3643 is engaged in a Flash event, and the TX pin is pulled high, the LED current is forced into Torch Mode at the programmed Torch current setting. If the TX pin is then pulled low before the Flash pulse terminates, the LED current returns to the previous Flash current level. At the end of the Flash time-out, whether the TX pin is high or low, the LED current turns off.

8.4.4 Input Voltage Flash Monitor (IVFM)

The LM3643 has the ability to adjust the flash current based upon the voltage level present at the IN pin utilizing the Input Voltage Flash Monitor (IVFM). The adjustable threshold IVFM-D ranges from 2.9 V to 3.6 V in 100-mV steps, with three different usage modes (Stop and Hold, Adjust Down Only, Adjust Up and Down). The Flags2 Register has the IVFM flag bit set when the input voltage crosses the IVFM-D value. Additionally, the IVFM-D threshold sets the input voltage boundary that forces the LM3643 to either stop ramping the flash current during start-up (Stop and Hold Mode) or to start decreasing the LED current during the flash (Down Adjust Only and Up and Down Adjust). In Adjust Up and Down mode, the IVFM-D value plus the hysteresis voltage threshold set the input voltage boundary that forces the LM3643 to start ramping the flash current back up towards the target.

Figure 30. IVFM Modes

8.4.5 Fault/Protections

8.4.5.1 Fault Operation

If the LM3643 enters a fault condition, the device sets the appropriate flag in the Flags1 and Flags2 Registers (0x0A and 0x0B), and place the device into standby by clearing the Mode Bits ([1],[0]) in the Enable Register. The LM3643 remains in standby until an I²C read of the Flags1 and Flags2 Registers are completed. Upon clearing the flags/faults, the device can be restarted (Flash, Torch, IR, etc.). If the fault is still present, the LM3643 re-enters the fault state and enters standby again.

8.4.5.2 Flash Time-Out

The Flash Time-Out period sets the amount of time that the Flash Current is being sourced from the current sources (LED1/2). The LM3643 has 16 timeout levels ranging from 10 ms to 400 ms (see Timing Configuration Register (0x08) for more detail).

8.4.5.3 Overvoltage Protection (OVP)

The output voltage is limited to typically 5 V (see V_OVP spec in the Electrical Characteristics). In situations such as an open LED, the LM3643 raises the output voltage in order to try and keep the LED current at its target value. When V_OUT reaches 5 V (typical) the overvoltage comparator trips and turns off the internal NFET. When V_OUT falls below the “V_OVP Off Threshold”, the LM3643 begins switching again. The mode bits are cleared, and the OVP flag is set, when an OVP condition is present for three rising OVP edges. This prevents momentary OVP events from forcing the device to shut down.

8.4.5.4 Current Limit

The LM3643 features two selectable inductor current limits that are programmable through the I²C-compatible interface. When the inductor current limit is reached, the LM3643 terminates the charging phase of the switching cycle. Switching resumes at the start of the next switching period. If the overcurrent condition persists, the device operates continuously in current limit.

Since the current limit is sensed in the NMOS switch, there is no mechanism to limit the current when the device operates in Pass Mode (current does not flow through the NMOS in pass mode). In Boost mode or Pass mode if V_OUT falls below 2.3 V, the device stops switching, and the PFET operates as a current source limiting the current to 200 mA. This prevents damage to the LM3643 and excessive current draw from the battery during output short-circuit conditions. The mode bits are not cleared upon a Current Limit event, but a flag is set.

8.4.5.5 NTC Thermistor Input (Torch/Temp)

The TORCH/TEMP pin, when set to TEMP mode, serves as a threshold detector and bias source for negative temperature coefficient (NTC) thermistors. When the voltage at TEMP goes below the programmed threshold, the LM3643 is placed into standby mode. The NTC threshold voltage is adjustable from 200 mV to 900 mV in 100-mV steps. The NTC bias current is set to 50 µA. The NTC detection circuitry can be enabled or disabled via the Enable Register. If enabled, the NTC block turns on and off during the start and stop of a Flash/Torch event.

Additionally, the NTC input looks for an open NTC connection and a shorted NTC connection. If the NTC input falls below 100 mV, the NTC short flag is set, and the device is disabled. If the NTC input rises above 2.3 V, the NTC Open flag is set, and the device is disabled. These fault detections can be individually disabled/enabled via the NTC Open Fault Enable bit and the NTC Short Fault Enable bit.

Figure 31. Temp Detection Diagram

8.4.5.6 Undervoltage Lockout (UVLO)

The LM3643 has an internal comparator that monitors the voltage at IN and forces the LM3643 into standby if the input voltage drops to 2.5 V. If the UVLO monitor threshold is tripped, the UVLO flag bit is set in the Flags1 Register (0x0A). If the input voltage rises above 2.5 V, the LM3643 is not available for operation until there is an I²C read of the Flags1 Register (0x0A). Upon a read, the Flags1 register is cleared, and normal operation can resume if the input voltage is greater than 2.5 V.

8.4.5.7 Thermal Shutdown (TSD)

When the LM3643 die temperature reaches 150°C, the thermal shutdown detection circuit trips, forcing the LM3643 into standby and writing a '1' to the corresponding bit of the Flags1 Register (0x0A) (Thermal Shutdown bit). The LM3643 is only allowed to restart after the Flags1 Register (0x0A) is read, clearing the fault flag. Upon restart, if the die temperature is still above 150°C, the LM3643 resets the Fault flag and re-enters standby.

8.4.5.8 LED and/or VOUT Short Fault

The LED Fault flags read back a '1' if the device is active in Flash or Torch mode and either active LED output experiences a short condition. The Output Short Fault flag reads back a '1' if the device is active in Flash or Torch mode and the boost output experiences a short condition. An LED short condition is determined if the voltage at LED1 or LED2 goes below 500 mV (typ.) while the device is in Torch or Flash mode. There is a deglitch time of 256 μs before the LED Short flag is valid and a deglitch time of 2.048 ms before the VOUT Short flag is valid. The LED Short Faults can be reset to '0' by removing power to the LM3643, setting HWEN to '0', setting the SW RESET bit to a '1', or by reading back the Flags1 Register (0x0A on LM3643). The mode bits are cleared upon an LED and/or V_OUT short fault.

8.5 Programming

8.5.1 Control Truth Table

MODE1	MODE0	STROBE EN	TORCH EN	STROBE PIN	TORCH PIN	ACTION
0	0	0	0	X	X	Standby
0	0	0	1	X	pos edge	Ext Torch
0	0	1	0	pos edge	X	Ext Flash
0	0	1	1	0	pos edge	Standalone Torch
0	0	1	1	pos edge	0	Standalone Flash
0	0	1	1	pos edge	pos edge	Standalone Flash
1	0	X	X	X	X	Int Torch
1	1	X	X	X	X	Int Flash
0	1	0	X	X	X	IRLED Standby
0	1	1	X	0	X	IRLED Standby
0	1	1	X	pos edge	X	IRLED enabled

8.5.2 I²C-Compatible Interface

8.5.2.1 Data Validity

The data on SDA must be stable during the HIGH period of the clock signal (SCL). In other words, the state of the data line can only be changed when SCL is LOW.

Figure 32. Data Validity Data

A pullup resistor between the controller's VIO line and SDA must be greater than [(VIO - V_OL) / 3 mA] to meet the V_OL requirement on SDA. Using a larger pullup resistor results in lower switching current with slower edges, while using a smaller pullup results in higher switching currents with faster edges.

8.5.2.2 Start and Stop Conditions

START and STOP conditions classify the beginning and the end of the I²C session. A START condition is defined as the SDA signal transitioning from HIGH to LOW while SCL line is HIGH. A STOP condition is defined as the SDA transitioning from LOW to HIGH while SCL is HIGH. The I²C master always generates START and STOP conditions. The I²C bus is considered busy after a START condition and free after a STOP condition. During data transmission, the I²C master can generate repeated START conditions. First START and repeated START conditions are equivalent, function-wise.

Figure 33. Start and Stop Conditions

8.5.2.3 Transferring Data

Every byte put on the SDA line must be eight bits long, with the most significant bit (MSB) transferred first. Each byte of data has to be followed by an acknowledge bit. The acknowledge related clock pulse is generated by the master. The master releases the SDA line (HIGH) during the acknowledge clock pulse. The LM3643 pulls down the SDA line during the 9th clock pulse, signifying an acknowledge. The LM3643 generates an acknowledge after each byte is received. There is no acknowledge created after data is read from the device.

After the START condition, the I²C master sends a chip address. This address is seven bits long followed by an eighth bit which is a data direction bit (R/W). The LM3643 7-bit address is 0x63. The device address for the LM3643A is 0x67. For the eighth bit, a '0' indicates a WRITE and a '1' indicates a READ. The second byte selects the register to which the data is written. The third byte contains data to write to the selected register.

Figure 34. Write Cycle W = Write (SDA = "0") R = Read (SDA = "1") Ack = Acknowledge
(SDA Pulled Down by Either Master or Slave) ID = Chip Address, 63h for LM3643

8.5.2.4 I²C-Compatible Chip Address

The device address for the LM3643 is 1100011 (0x63). The device address for the LM3643A is 1100111 (0x67). After the START condition, the I²C-compatible master sends the 7-bit address followed by an eighth read or write bit (R/W). R/W = 0 indicates a WRITE and R/W = 1 indicates a READ. The second byte following the device address selects the register address to which the data is written. The third byte contains the data for the selected register.

Figure 35. I²C-Compatible Chip Address

8.6 Register Descriptions

REGISTER NAME	INTERNAL HEX ADDRESS	POWER ON/RESET VALUE
REGISTER NAME	INTERNAL HEX ADDRESS	LM3643
Enable Register	0x01	0x80
IVFM Register	0x02	0x01
LED1 Flash Brightness Register	0x03	0xBF
LED2 Flash Brightness Register	0x04	0x3F
LED1 Torch Brightness Register	0x05	0xBF
LED2 Torch Brightness Register	0x06	0x3F
Boost Configuration Register	0x07	0x09
Timing Configuration Register	0x08	0x1A
TEMP Register	0x09	0x08
Flags1 Register	0x0A	0x00
Flags2 Register	0x0B	0x00
Device ID Register	0x0C	0x02
Last Flash Register	0x0D	0x00

8.6.1 Enable Register (0x01)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
TX Pin Enable 0 = Disabled 1 = Enabled (Default )	Strobe Type 0 = Level Triggered (Default) 1 = Edge Triggered	Strobe Enable 0 = Disabled (Default ) 1 = Enabled	TORCH/TEMP Pin Enable 0 = Disabled (Default ) 1 = Enabled	Mode Bits: M1, M0 00 = Standby (Default) 01 = IR Drive 10 = Torch 11 = Flash		LED2 Enable 0 = OFF (Default ) 1 = ON	LED1 Enable 0 = OFF (Default) 1 = ON

NOTE

Edge Strobe Mode is not valid in IR MODE. Switching between Level and Edge Strobe Types while the device is enabled is not recommended.

In Edge or Level Strobe Mode, it is recommended that the trigger pulse width be set greater than 1 ms to ensure proper turn-on of the device.

8.6.2 IVFM Register (0x02)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	UVLO Circuitry (Default) 0 = Disabled (Default) 1 = Enabled	IVFM Levels 000 = 2.9 V (Default) 001 = 3 V 010 = 3.1 V 011 = 3.2 V 100 = 3.3 V 101 = 3.4 V 110 = 3.5 V 111 = 3.6 V			IVFM Hysteresis 0 = 0 mV (Default) 1 = 50 mV	IVFM Selection 00 = Disabled 01 = Stop and Hold Mode (Default) 10 = Down Mode 11 = Up and Down Mode

NOTE

IVFM Mode Bits are static once the LM3643 is enabled in Torch, Flash or IR modes. If the IVFM mode needs to be updated, disable the device and then change the mode bits to the desired state.

8.6.3 LED1 Flash Brightness Register (0x03)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
LED2 Flash Current Override 0 = LED2 Flash Current is not set to LED1 Flash Current 1 = LED2 Flash Current is set to LED1 Flash Current (Default)	LED1 Flash Brightness Level I_FLASH1/2 (mA) ≈ (Brightness Code × 11.725 mA) + 10.9 mA 0000000 = 10.9 mA ....................... 0111111 = 729 mA (Default) ....................... 1111111 = 1.5 A

8.6.4 LED2 Flash Brightness Register (0x04)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	LED2 Flash Brightness Levels I_FLASH1/2 (mA) ≈ (Brightness Code × 11.725 mA) + 10.9 mA 0000000 = 10.9 mA ....................... 0111111 = 729 mA (Default) ....................... 1111111 = 1.5 A

8.6.5 LED1 Torch Brightness Register (0x05)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
LED2 Torch Current Override 0 = LED2 Torch Current is not set to LED1 Torch Current 1 = LED2 Torch Current is set to LED1 Torch Current (Default)	LED1 Torch Brightness Levels I_TORCH1/2 (mA) ≈ (Brightness Code × 1.4 mA) + 0.977 mA 0000000 = 0.977 mA ....................... 0111111 = 89.3 mA (Default) ....................... 1111111 = 179 mA

8.6.6 LED2 Torch Brightness Register (0x06)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	LED2 Torch Brightness Levels I_TORCH1/2 (mA) ≈ (Brightness Code × 1.4 mA) + 0.977 mA 0000000 = 0.977 mA ....................... 0111111 = 89.3 mA (Default) ....................... 1111111 = 179 mA

8.6.7 Boost Configuration Register (0x07)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
Software Reset Bit 0 = Not Reset (Default) 1 = Reset	RFU	RFU	RFU	LED Pin Short Fault Detect 0 = Disabled 1 = Enabled (Default)	Boost Mode 0 = Normal (Default) 1 = Pass Mode Only	Boost Frequency Select 0 = 2 MHz (Default) 1 = 4 MHz	Boost Current Limit Setting 0 = 1.9 A 1 = 2.8 A (Default)

8.6.8 Timing Configuration Register (0x08)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	Torch Current Ramp Time 000 = No Ramp 001 = 1 ms (Default) 010 = 32 ms 011 = 64 ms 100 = 128 ms 101 = 256 ms 110 = 512 ms 111 = 1024 ms			Flash Time-Out Duration 0000 = 10 ms 0001 = 20 ms 0010 = 30 ms 0011 = 40 ms 0100 = 50 ms 0101 = 60 ms 0110 = 70 ms 0111 = 80 ms 1000 = 90 ms 1001 = 100 ms 1010 = 150 ms (Default) 1011 = 200 ms 1100 = 250 ms 1101 = 300 ms 1110 = 350 ms 1111 = 400 ms

8.6.9 TEMP Register (0x09)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	TORCH Polarity 0 = Active High (Default) (Pulldown Resistor Enabled) 1 = Active Low (Pulldown Resistor Disabled)	NTC Open Fault Enable 0 = Disabled (Default) 1 =Enable	NTC Short Fault Enable 0 = Disabled (Default) 1 =Enable	TEMP Detect Voltage Threshold 000 = 0.2 V 001 = 0.3 V 010 = 0.4 V 011 = 0.5 V 100 = 0.6 V (Default) 101 = 0.7 V 110 = 0.8 V 111 = 0.9 V			TORCH/TEMP Function Select 0 = TORCH (Default) 1 = TEMP

NOTE

The Torch Polarity bit is static once the LM3643 is enabled in Torch, Flash or IR modes. If the Torch Polarity bit needs to be updated, disable the device and then change the Torch Polarity bit to the desired state.

8.6.10 Flags1 Register (0x0A)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
TX Flag	V_OUT Short Fault	VLED1 Short Fault	VLED2 Short Fault	Current Limit Flag	Thermal Shutdown (TSD) Fault	UVLO Fault	Flash Time-Out Flag

8.6.11 Flags2 Register (0x0B)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	RFU	RFU	NTC Short Fault	NTC Open Fault	IVFM Trip Flag	OVP Fault	TEMP Trip Fault

8.6.12 Device ID Register (0x0C)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	RFU	Device ID '000'			Silicon Revision Bits '010'

8.6.13 Last Flash Register (0x0D)

Bit 7	Bit 6	Bit 5	Bit 4	Bit 3	Bit 2	Bit 1	Bit 0
RFU	The value stored is always the last current value the IVFM detection block set. I_LED = I_{FLASH – TARGET} × ((Code + 1) / 128)

9 Applications and Implementation

NOTE

Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI’s customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality.

9.1 Application Information

The LM3643 can drive two flash LEDs at currents up to 1.5 A per LED. The total LED current the LM3643 boost can deliver is 1.5 A (I_LED1 + I_LED2 ). The 2-MHz/4-MHz DC-DC boost regulator allows for the use of small value discrete external components.

9.2 Typical Application

Figure 36. LM3643 Typical Application

9.2.1 Design Requirements

Example requirements based on default register values:

DESIGN PARAMETER	EXAMPLE VALUE
Input voltage range	2.5 V to 5.5 V
Brightness control	I²C Register
LED configuration	2 parallel flash LEDs
Boost switching frequency	2 MHz (4 MHz selectable)
Flash brightness	750 mA per LED

9.2.2 Detailed Design Procedure

9.2.2.1 Output Capacitor Selection

The LM3643 is designed to operate with a 10-µF ceramic output capacitor. When the boost converter is running, the output capacitor supplies the load current during the boost converter on-time. When the NMOS switch turns off, the inductor energy is discharged through the internal PMOS switch, supplying power to the load and restoring charge to the output capacitor. This causes a sag in the output voltage during the on-time and a rise in the output voltage during the off-time. The output capacitor is therefore chosen to limit the output ripple to an acceptable level depending on load current and input/output voltage differentials and also to ensure the converter remains stable.

Larger capacitors such as a 22-µF or capacitors in parallel can be used if lower output voltage ripple is desired. To estimate the output voltage ripple considering the ripple due to capacitor discharge (ΔV_Q) and the ripple due to the capacitors ESR (ΔV_ESR) use the following equations:

For continuous conduction mode, the output voltage ripple due to the capacitor discharge is:

Equation 1. LM3643 LM3643A 30171827.gif

The output voltage ripple due to the output capacitors ESR is found by:

Equation 2. LM3643 LM3643A 30171828.gif

In ceramic capacitors the ESR is very low so the assumption is that 80% of the output voltage ripple is due to capacitor discharge and 20% from ESR. Table 1 lists different manufacturers for various output capacitors and their case sizes suitable for use with the LM3643.

9.2.2.2 Input Capacitor Selection

Choosing the correct size and type of input capacitor helps minimize the voltage ripple caused by the switching of the LM3643 boost converter and reduce noise on the boost converter's input pin that can feed through and disrupt internal analog signals. In the typical application circuit a 10-µF ceramic input capacitor works well. It is important to place the input capacitor as close as possible to the LM3643 input (IN) pin. This reduces the series resistance and inductance that can inject noise into the device due to the input switching currents. Table 1 lists various input capacitors recommended for use with the LM3643.

Table 1. Recommended Input/Output Capacitors (X5R/X7R Dielectric)

MANUFACTURER	PART NUMBER	VALUE	CASE SIZE	VOLTAGE RATING
TDK Corporation	C1608JB0J106M	10 µF	0603 (1.6 mm × 0.8 mm × 0.8 mm)	6.3 V
TDK Corporation	C2012JB1A106M	10 µF	0805 (2.0 mm × 1.25 mm × 1.25 mm)	10 V
Murata	GRM188R60J106M	10 µF	0603 (1.6 mm x 0.8 mm x 0.8 mm)	6.3 V
Murata	GRM21BR61A106KE19	10 µF	0805 (2.0 mm × 1.25 mm × 1.25 mm)	10 V

9.2.2.3 Inductor Selection

The LM3643 is designed to use a 0.47-µH or 1-µH inductor. Table 2 lists various inductors and their manufacturers that work well with the LM3643. When the device is boosting (V_OUT > V_IN) the inductor is typically the largest area of efficiency loss in the circuit. Therefore, choosing an inductor with the lowest possible series resistance is important. Additionally, the saturation rating of the inductor should be greater than the maximum operating peak current of the LM3643. This prevents excess efficiency loss that can occur with inductors that operate in saturation. For proper inductor operation and circuit performance, ensure that the inductor saturation and the peak current limit setting of the LM3643 are greater than I_PEAK in the following calculation:

Equation 3. LM3643 LM3643A 30171829.gif

where

ƒ_SW = 2 or 4 MHz

Efficiency details can be found in the Application Curves.

Table 2. Recommended Inductors

MANUFACTURER	L	PART NUMBER	DIMENSIONS (L×W×H)	I_SAT	R_DC
TOKO	0.47 µH	DFE201610P-R470M	2.0 mm x 1.6 mm x 1.0 mm	4.1 A	32 mΩ
TOKO	1 µH	DFE201610P-1R0M	2.0 mm x 1.6 mm x 1.0 mm	3.7 A	58 mΩ

9.2.3 Application Curves

Ambient temperature is 25°C, input voltage is 3.6 V, HWEN = V_IN, C_IN = 2 × 10 µF, C_OUT = 2 × 10 µF and L = 1 µH, unless otherwise noted.

I_LED = 1.5 A

ƒ_SW = 2 MHz

Flash

Figure 37. 2-MHz LED Efficiency vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 2 MHz	Flash
V_LED = 3.55 V

Figure 39. LED Efficiency vs Input Voltage

I_LED = 1.5 A

ƒ_SW = 2 MHz

Flash

Figure 38. 4-MHz LED Efficiency vs Input Voltage

I_LED = 1.5 A	ƒ_SW = 4 MHz	Flash
V_LED = 3.55 V

Figure 40. LED Efficiency vs Input Voltage

I_LED = 1 A	ƒ_SW = 2 MHz	Flash
V_LED = 3.32 V

Figure 41. LED Efficiency vs Input Voltage

I_{LED1 and LED2} = 729 mA	Flash
V_LED = 3.18 V	ƒ_SW = 2 MHz

Figure 43. LED Efficiency vs Input Voltage

I_LED = 179 mA	ƒ_SW = 4 MHz
V_LED = 2.83 V	Torch

Figure 45. LED Efficiency vs Input Voltage

I_{LED1 and LED2} = 179 mA	ƒ_SW = 4 MHz
V_LED = 2.83 V	Torch

Figure 47. LED Efficiency vs Input Voltage

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
V_LED = 3.18 V

Figure 49. Ramp Down

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
V_LED = 3.18 V

Figure 51. Ripple @ 2 MHz

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
V_LED = 3.18 V	V_IVFM= 3.2 V

Figure 53. IVFM - Ramp and Hold

	I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
	V_LED = 3.18 V	V_IVFM= 3.2 V

Figure 55. IVFM - Up and Down Adjust

I_LED = 729 mA	ƒ_SW = 2 MHz	Flash
V_LED = 3.18 V

Figure 42. LED Efficiency vs Input Voltage

I_LED = 179 mA	Torch
V_LED = 2.83 V	ƒ_SW = 2 MHz

Figure 44. LED Efficiency vs Input Voltage

I_{LED1 and LED2} = 179 mA	ƒ_SW = 2 MHz
V_LED = 2.83 V	Torch

Figure 46. LED Efficiency vs Input Voltage

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
V_LED = 3.18 V

Figure 48. Start-Up

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
V_LED = 3.18 V

Figure 50. TX Interrupt

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 4 MHz
V_LED = 3.18 V

Figure 52. Ripple @ 4 MHz

I_LED1 = I_LED2 = 730 mA	ƒ_SW = 2 MHz
V_LED = 3.18 V	V_IVFM= 3.2 V

Figure 54. IVFM - Down Adjust Only

10 Power Supply Recommendations

The LM3643 is designed to operate from an input voltage supply range between 2.5 V and 5.5 V. This input supply must be well regulated and capable to supply the required input current. If the input supply is located far from the LM3643 additional bulk capacitance may be required in addition to the ceramic bypass capacitors.

11 Layout

11.1 Layout Guidelines

The high switching frequency and large switching currents of the LM3643 make the choice of layout important. The following steps should be used as a reference to ensure the device is stable and maintains proper LED current regulation across its intended operating voltage and current range.

Place C_IN on the top layer (same layer as the LM3643) and as close to the device as possible. The input capacitor conducts the driver currents during the low-side MOSFET turn-on and turn-off and can detect current spikes over 1 A in amplitude. Connecting the input capacitor through short, wide traces to both the IN and GND pins reduces the inductive voltage spikes that occur during switching which can corrupt the V_IN line.
Place C_OUT on the top layer (same layer as theLM3643) and as close as possible to the OUT and GND pin. The returns for both C_IN and C_OUT should come together at one point, as close to the GND pin as possible. Connecting C_OUT through short, wide traces reduce the series inductance on the OUT and GND pins that can corrupt the V_OUT and GND lines and cause excessive noise in the device and surrounding circuitry.
Connect the inductor on the top layer close to the SW pin. There should be a low-impedance connection from the inductor to SW due to the large DC inductor current, and at the same time the area occupied by the SW node should be small so as to reduce the capacitive coupling of the high dV/dT present at SW that can couple into nearby traces.
Avoid routing logic traces near the SW node so as to avoid any capacitively coupled voltages from SW onto any high-impedance logic lines such as TORCH/TEMP, STROBE, HWEN, SDA, and SCL. A good approach is to insert an inner layer GND plane underneath the SW node and between any nearby routed traces. This creates a shield from the electric field generated at SW.
Terminate the Flash LED cathodes directly to the GND pin of the LM3643. If possible, route the LED returns with a dedicated path so as to keep the high amplitude LED currents out of the GND plane. For Flash LEDs that are routed relatively far away from the LM3643, a good approach is to sandwich the forward and return current paths over the top of each other on two layers. This helps reduce the inductance of the LED current paths.

11.2 Layout Example

Figure 56. Layout Example

12 器件和文档支持

12.1 器件支持

12.1.1 Third-Party Products Disclaimer

TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.

12.2 相关文档

12.2.1 相关链接

Table 3 列出了快速访问链接。范围包括技术文档、支持与社区资源、工具和软件，以及样片或购买的快速访问。

Table 3. 相关链接

器件	产品文件夹	样片与购买	技术文档	工具与软件	支持与社区
LM3643	请单击此处	请单击此处	请单击此处	请单击此处	请单击此处
LM3643A	请单击此处	请单击此处	请单击此处	请单击此处	请单击此处

12.3 商标

All trademarks are the property of their respective owners.

12.4 静电放电警告

ESD 可能会损坏该集成电路。德州仪器 (TI) 建议通过适当的预防措施处理所有集成电路。如果不遵守正确的处理措施和安装程序 , 可能会损坏集成电路。

ESD 的损坏小至导致微小的性能降级 , 大至整个器件故障。精密的集成电路可能更容易受到损坏 , 这是因为非常细微的参数更改都可能会导致器件与其发布的规格不相符。

12.5 术语表

SLYZ022 — TI 术语表。

这份术语表列出并解释术语、缩写和定义。

13 机械、封装和可订购信息

以下页中包括机械、封装和可订购信息。这些信息是针对指定器件可提供的最新数据。这些数据会在无通知且不对本文档进行修订的情况下发生改变。欲获得该数据表的浏览器版本，请查阅左侧的导航栏。

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TI 组件未获得用于 FDA Class III（或类似的生命攸关医疗设备）的授权许可，除非各方授权官员已经达成了专门管控此类使用的特别协议。

只有那些 TI 特别注明属于军用等级或“增强型塑料”的 TI 组件才是设计或专门用于军事/航空应用或环境的。购买者认可并同意，对并非指定面向军事或航空航天用途的 TI组件进行军事或航空航天方面的应用，其风险由客户单独承担，并且由客户独力负责满足与此类使用相关的所有法律和法规要求。

TI 已明确指定符合 ISO/TS16949 要求的产品，这些产品主要用于汽车。在任何情况下，因使用非指定产品而无法达到 ISO/TS16949要求，TI不承担任何责任。

产品

数字音频: www.ti.com.cn/audio
放大器和线性器件: www.ti.com.cn/amplifiers
数据转换器: www.ti.com.cn/dataconverters
DLP® 产品: www.dlp.com
DSP - 数字信号处理器: www.ti.com.cn/dsp
时钟和计时器: www.ti.com.cn/clockandtimers
接口: www.ti.com.cn/interface
逻辑: www.ti.com.cn/logic
电源管理: www.ti.com.cn/power
微控制器 (MCU): www.ti.com.cn/microcontrollers
RFID 系统: www.ti.com.cn/rfidsys
OMAP应用处理器: www.ti.com/omap
无线连通性: www.ti.com.cn/wirelessconnectivity

应用

通信与电信: www.ti.com.cn/telecom
计算机及周边: www.ti.com.cn/computer
消费电子: www.ti.com/consumer-apps
能源: www.ti.com/energy
工业应用: www.ti.com.cn/industrial
医疗电子: www.ti.com.cn/medical
安防应用: www.ti.com.cn/security
汽车电子: www.ti.com.cn/automotive
视频和影像: www.ti.com.cn/video

德州仪器在线技术支持社区: www.deyisupport.com