ZHCSE56O August   2012  – December 2015 LM3262

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
  4. 4 修订历史记录
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 System Characteristics
    7. 6.7 Timing Requirements
    8. 6.8 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Circuit Operation
      2. 7.3.2 Internal Synchronous Rectification
      3. 7.3.3 Current Limiting
      4. 7.3.4 Dynamically Adjustable Output Voltage
      5. 7.3.5 Thermal Overload Protection
      6. 7.3.6 Soft Start
    4. 7.4 Device Functional Modes
      1. 7.4.1 PWM Mode Operation
      2. 7.4.2 Bypass Mode Operation
      3. 7.4.3 ECO Mode Operation
      4. 7.4.4 Sleep Mode Operation
      5. 7.4.5 Shutdown Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Inductor Selection
          1. 8.2.2.1.1 Method 1
          2. 8.2.2.1.2 Method 2
        2. 8.2.2.2 Capacitor Selection
        3. 8.2.2.3 Setting The Output Voltage
        4. 8.2.2.4 FB
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Energy Efficiency
      2. 10.1.2 EMI
      3. 10.1.3 Manufacturing Considerations
    2. 10.2 Layout Examples
      1. 10.2.1 Component Placement
    3. 10.3 DSBGA Assembly and Use
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 文档支持
      1. 11.2.1 相关文档　
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 Glossary
  12. 12机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range (unless otherwise noted)(1)(2)
MIN MAX UNIT
VIN to SGND −0.2 6 V
PGND to SGND −0.2 0.2 V
EN, VCON, BPEN (SGND − 0.2) (VIN + 0.2) V
FB, SW (PGND − 0.2) (VIN + 0.2) V
Continuous power dissipation(3) Internally limited
Junction temperature, TJ-MAX 150 °C
Maximum lead temperature (soldering, 10 sec) 260 °C
Storage temperature, Tstg −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 pins.
(3) Internal thermal shutdown circuitry protects the device from permanent damage. Thermal shutdown engages at TJ = 150°C (typical) and disengages at TJ = 130°C (typical).

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) ±2000 V
Charged-device model (CDM), per JEDEC specification JESD22-C101(2) ±1250
(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.

6.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)(1)
MIN MAX UNIT
Input voltage, VIN 2.5 5.5 V
Recommended load current PWM mode 0 800 mA
Bypass mode 0 1000 mA
Junction temperature, TJ –30 125 °C
Ambient temperature, TA(2) −30 90 °C
(1) All voltages are with respect to the potential at the GND pins
(2) In applications where high-power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature may have to be de-rated. Maximum ambient temperature (TA-MAX) is dependent on the maximum operating junction temperature (TJ-MAX-OP = 125°C), the maximum power dissipation of the device in the application (PD-MAX), and the junction-to ambient thermal resistance of the part/package in the application (RθJA), as given by the following equation: TA-MAX = TJ-MAX-OP – (RθJA × PD-MAX).

6.4 Thermal Information

THERMAL METRIC(1) LM3262 UNIT
YFQ (DSBGA)
9 PINS
RθJA Junction-to-ambient thermal resistance 85 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics

Unless otherwise noted, all specifications apply to the 典型应用电路 with: VIN = EN = 3.6 V and
BPEN = NC = 0 V. All typical (TYP) limits apply for TA = TJ = 25°C, and all minimum (MIN) and maximum (MAX) apply over the full operating ambient temperature range (−30°C ≤ TA = TJ ≤ +90°C), unless otherwise specified.(1)(2)(3)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
VFB, MIN Feedback voltage at minimum setting PWM mode, VCON = 0.16 V(4) 0.38 0.4 0.42 V
VFB, MAX Feedback voltage at maximum setting PWM mode, VCON = 1.44 V, VIN = 4 V 3.55 3.6 3.65 V
ISHDN Shutdown supply current EN = SW = VCON = FB = BPEN = NC =0 V(5) 0.1 1 µA
IQ_PWM PWM mode quiescent current PWM mode, No switching
VCON = 0.13 V, FB = 1 V(6)		 650 795 µA
IQ_SLEEP Low-power sleep mode EN = VIN, BPEN = NC = 0V, SW = tri state
VCON < 0.8 V, FB = 2.05 V(7)		 25 µA
IQ_ECO ECO mode quiescent current ECO mode, No switching
VCON = 0.8 V, FB = 2.05 V(6)		 60 µA
ILIM,P PFET switch peak current limit See(8) 1300 1450 1600 mA
ILIM, BP BPFET switch peak current limit VFB = VIN – 1 V 310 400 mA
ƒOSC Internal oscillator frequency 5.7 6 6.3 MHz
VIH EN, BPEN logic high input threshold 1.2 V
VIL EN, BPEN logic low input threshold 0.4 V
Gain VCON to VOUT gain 0.16 V ≤ VCON ≤ 1.44 V(9) 2.5 V/V
IVCON VCON pin leakage current VCON = 1 V –1 1 µA
VBP, NEG Auto bypass detection negative threshold VCON = 1.2 V (VOUT-SET = 3 V)
VIN = 3.2 V, RL = 6 Ω (IOUT = 500 mA)(10)		 165 200 235 mV
VBP, NEG Auto bypass detection positive threshold VCON = 1.2 V (VOUT-SET = 3 V)
VIN = 3.25 V, RL = 6 Ω (IOUT = 500 mA)(11)		 215 250 285 mV
IBP, SLEW BPEN = High, Forced bypass 1600 mA
(1) All voltages are with respect to the potential at the GND pins.
(2) Minimum and maximum limits are specified by design, test, or statistical analysis.
(3) The parameters in the electrical characteristics table are tested under open loop conditions at VIN = 3.6 V unless otherwise specified. For performance over the input voltage range and closed-loop results, refer to Typical Characteristics.
(4) All 0.4-V VOUT specifications are at steady-state only.
(5) Shutdown current includes leakage current of PFET.
(6) Iq specified here is when the device is not switching. For operating input current at no load, refer to Typical Characteristics.
(7) FB has 200 kΩ to SGND.
(8) Current limit is built-in, fixed, and not adjustable.
(9) Care should be taken to keep the VCON pin voltage less than the VIN pin voltage as this can place the device into a manufacturing test mode.
(10) Entering bypass mode, VIN is compared to the programmed output voltage (2.5 × VCON). When VIN − (2.5 × VCON) falls below VBP,NEG longer than TBP,NEG, the bypass FET turns on, and the switching FET turns on.
(11) Bypass mode is exited when VIN − (2.5 × VCON) exceeds VBP,POS longer than TBP,POS, and PWM mode resumes. The hysteresis for the bypass detection threshold VBP,POS − VBP,NEG is always positive and is approximately 50 mV.

6.6 System Characteristics

The following parameters are specified by design and verifications providing the component values in the 典型应用电路 are used. These parameters are not verified by production testing. Minimum (MIN) and maximum (MAX) values are specified over the ambient temperature range TA = −30°C ≤ TA ≤ +90°C and over the VIN range = 2.5 V to 5.5 V, unless otherwise specified; L = 0.5 μH, DCR = 50 mΩ, CIN = 10 μF, 6.3 V, 0402 (1005), COUT = 4.7 μF, 6.3 V, 0402 (1005). For bench evaluation, see (1).
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
D Maximum duty cycle MODE = LOW 100%
IOUT Maximum output current capability 2.5 V ≤ VIN ≤ 5.5 V
2.5 × VCON ≤ VIN – 285 mV		 800 mA
2.5 V ≤ VIN ≤ 5.5 V
2.5 × VCON ≤ VIN – 165 mV, bypass mode		 1000
VOUT linearity VCON = 0.16 V to 1.44 V 0 mA ≤ IOUT ≤ 800 mA(2) –3% 3%
–50 50 mV
η Efficiency VIN = 3.8 V, VOUT = 0.8 V
IOUT = 10 mA, ECO mode		 71%
VIN = 3.8 V, VOUT = 2.5 V
IOUT = 200 mA, PWM mode		 92%
VIN = 3.8 V, VOUT = 3.4 V
IOUT = 500 mA, PWM mode		 93%
LINE_tr Line transient response VIN = 3.6 V to 4.2 V, TR = TF = 10 µs,
IOUT = 100 mA, VOUT = 0.8 V		 50 mVpk
LOAD_tr Load transient response VIN = 3.1/3.6/4.5 V, VOUT = 0.8 V
IOUT = 50 mA to 150 mA
TR = TF = 10 µs, 		50 mVpk
(1) When the LM3262 device is being evaluated apart from a normal system design or on a PCB other than the TI LM3262 evaluation module, user should ensure that a 50-µF to 100-μF ceramic input capacitor is added to the PCB to keep input voltage from sagging during rapid load transitions.
(2) Linearity limits are ±3% or ±50 mV, whichever is larger. VOUT is monotonic in nature with respect to VCON input.

6.7 Timing Requirements

MIN NOM MAX UNIT
TVCON_TR VOUT rise time VCON change to 90%; VIN = 3.7 V, VOUT = 1.4 V to 3.4 V
0.1 µs < VCON_TR < 1 µs, RL = 12 Ω		 5 µs
VOUT fall time VCON change to 10%; VIN = 3.7 V, VOUT = 3.4 V to 1.4 V
0.1 µs < VCON_TR < 1 µs, RL = 12 Ω		 5 µs
TON Turnon time (time for output to reach 95% final value after Enable low-to-high transition)
EN = low-to-high, VIN = 4.2 V , VOUT = 3.4 V
IOUT ≤ 1 mA, COUT = 4.7 µF 		50 µs
TBP, NEG Auto bypass detect negative threshold delay time(1) 10 µs
TBP, POS Auto bypass detect positive threshold delay time(2) 0.1 µs
(1) Entering bypass mode, VIN is compared to the programmed output voltage (2.5 × VCON). When VIN − (2.5 × VCON) falls below VBP, NEG longer than TBP, NEG, the bypass FET turns on, and the switching FET turns on.
(2) Bypass mode is exited when VIN − (2.5 × VCON) exceeds VBP, POS longer than TBP, POS, and PWM mode resumes. The hysteresis for the bypass detection threshold VBP, POS − VBP, NEG is always positive and will be approximately 50 mV.

6.8 Typical Characteristics

VIN = EN = 3.6 V, L = 0.5 µH, CIN = 10 µF, COUT = 4.7 µF and TA = 25°C, unless otherwise noted.
LM3262 30168731.png
SW = VCON = EN = BPEN = 0V
Figure 1. Shutdown Current vs Temperature
LM3262 30168761.gif
No Switching FB = 1 V VCON = 0.13 V
Figure 3. Quiescent Current vs Supply Voltage
LM3262 30168734.png
VOUT = 2 V IOUT = 200 mA
Figure 5. Switching Frequency vs Temperature
LM3262 30168780.png
VIN = 3.8 V VOUT = 0.6 V
Figure 7. Output Voltage vs Output Current
LM3262 30168773.gif
Figure 9. ECO-PWM Mode Threshold Current
vs Output Voltage
LM3262 30168768.gif
Figure 11. Closed-Loop Current Limit vs Temperature
LM3262 30168718.png
VIN = 3.6 V VOUT = 2 V IOUT = 200 mA
Figure 13. Output Voltage Ripple in PWM Mode
LM3262 30168720.png
VIN = 4 V VOUT = 0.4 V to 3.6 V RLOAD = 10 Ω
Figure 15. VCON Transient Response
LM3262 30168724.png
VIN = 3.6 V VOUT = 0.5 V IOUT = 500 mA to 60 mA
Figure 17. Load Transient Response
LM3262 30168727.png
VIN = 4.2 V VOUT = 3.4 V RLOAD = 3.6 kΩ
Figure 19. Start-Up
LM3262 30168728.png
VOUT = 2 V RLOAD = 10 Ω→ 0 Ω
Figure 21. Timed Current Limit
LM3262 30168760.gif
VCON < 80 mV EN = VIN BPEN = 0
Figure 2. Sleep Mode Current vs Temperature
LM3262 30168758.gif
Closed Loop Switching No load
Figure 4. ECO Mode Supply Current vs Output Voltage
LM3262 30168716.gif
VOUT = 2 V RLOAD = 10 Ω
Figure 6. Output Voltage vs Supply Voltage
LM3262 30168782.png
VIN = 3.8 V VOUT = 2 V
Figure 8. Output Voltage vs Output Current
LM3262 30168775.gif
Figure 10. PWM-ECO Mode Threshold Current
vs Output Voltage
LM3262 30168737.png
Figure 12. EN High Threshold vs Supply Voltage
LM3262 30168719.png
VOUT = 2 V IOUT = 50 mA
Figure 14. Output Voltage Ripple in ECO Mode
LM3262 30168723.png
VIN = 3.6 V to 4.2 V VOUT = 0.6 V IOUT = 750 mA
Figure 16. Line Transient Response
LM3262 30168729.png
VIN = 4.2 V VOUT = 3.1 V IOUT = 200 mA to 750 mA
Figure 18. Load Transient Response
LM3262 30168717.png
VIN = 4.2 V VOUT = 3.4 V RLOAD = 10 Ω
Figure 20. Shutdown
LM3262 30168769.gif
RLOAD = 10 Ω
Figure 22. Low VCON Voltage vs Output Voltage