SLVS038I January   1989  – July 2016 TL2842 , TL2843 , TL2844 , TL2845 , TL3842 , TL3843 , TL3844 , TL3845

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  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 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 Pulse-by-Pulse Current Limiting
      2. 7.3.2 Error Amplifier With Low Output Resistance
      3. 7.3.3 High-Current Totem-Pole Output
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Technique
      2. 7.4.2 Slope Compensation
  8. 8 Application and Implementation
    1. 8.1 Typical Application
      1. 8.1.1 Design Requirements
      2. 8.1.2 Detailed Design Procedure
        1. 8.1.2.1 Current-Sense Circuit
        2. 8.1.2.2 Error-Amplifier Configuration
        3. 8.1.2.3 Oscillator Section
      3. 8.1.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Feedback Traces
      2. 10.1.2 Input/Output Capacitors
      3. 10.1.3 Compensation Components
      4. 10.1.4 Traces and Ground Planes
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Related Links
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

封装选项

请参考 PDF 数据表获取器件具体的封装图。

机械数据 (封装 | 引脚)
  • D|8
  • D|14
  • P|8
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)
MIN MAX UNIT
VCC Supply Voltage(2) Self limiting —
VI Analog input voltage range, VFB and ISENSE –0.3 6.3 V
VO Output Voltage 35 V
VI Input Voltage, VC and D Package only 35 V
ICC Supply current 30 mA
IO Output current ±1 A
error amplifier output sink current 10 mA
TJ Virtual junction temperature 150 °C
Output energy (capacitive load) 5 µJ
Tstg Storage temperature –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 device GND pin.

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all pins(1) 3000 V
Charged device model (CDM), per JEDEC specification JESD22-C101, all pins(2) 3000
(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)
MIN TYP MAX UNIT
VCC and VC(1) Supply Voltage 30 V
VI, RT/CT Input Voltage 0 5.5 V
VI, VFB and ISENSE Input Voltage 0 5.5 V
VO, OUTPUT Output voltage 0 30 V
VO, POWER GROUND(1) Output voltage –0.1 1 V
ICC Supply current, externally limited 25 mA
IO Average output current 200 mA
IO(ref) Reference output current –20 mA
fOSC Oscillator frequency 100 500 kHz
TA Operating free-air temperature TL284x –40 85 °C
TL384x 0 70
(1) These recommended voltages for VC and POWER GROUND apply only to the D package.

6.4 Thermal Information

THERMAL METRIC(1) TLx84x UNIT
D (SOIC) D (SOIC) P (PDIP)
8 PINS 14 PINS 8 PINS
RθJA Junction-to-ambient thermal resistance 97 86 85 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report.

6.5 Electrical Characteristics

over operating free-air temperature range, VCC = 15 V(2), RT = 10 kΩ, CT = 3.3 nF (unless otherwise noted)
PARAMETER TEST CONDITIONS(1) TL284x TL384x UNIT
MIN TYP(1) MAX MIN TYP(1) MAX
Reference Section
Output voltage IO = 1 mA, TA = 25°C 4.95 5 5.05 4.9 5 5.1 V
Line regulation VCC = 12 V to 25 V 6 20 6 20 mV
Load regulation IO = 1 mA to 20 mA 6 25 6 25 mV
Temperature coefficient of output voltage 0.2 0.4 0.2 0.4 mV/°C
Output voltage with worst-case variation VCC = 12 V to 25 V, IO = 1 mA to 20 mA 4.9 5.1 4.82 5.18 V
Output noise voltage f = 10 Hz to 10 kHz, TA = 25°C 50 50 µV
Output-voltage long-term drift After 1000 h at TA = 25°C 5 25 5 25 mV
Short-circuit output current –30 –100 –180 –30 –100 –180 mA
Oscillator Section
Oscillator frequency(3) TA = 25°C 47 52 57 47 52 57 kHz
Frequency change with supply voltage VCC = 12 V to 25 V 2 10 2 10 Hz/kHz
Frequency change with temperature 50 50 Hz/kHz
peak-to-peak amplitude at RT/CT 1.7 1.7 V
Error-Amplifier Section
Feedback input voltage COMP at 2.5 V 2.45 2.50 2.55 2.42 2.50 2.58 V
Input bias current –0.3 –1 –0.3 –2 µA
Open-loop voltage amplification VO = 2 V to 4 V 65 90 65 90 dB
Gain-bandwidth product 0.7 1 0.7 1 MHz
Supply-voltage rejection ratio VCC = 12 V to 25 V 60 70 60 70 dB
Output sink current VFB, at 2.7 V, COMP at 1.1 V 2 6 2 6 mA
Output source current VFB, at 2.3 V, COMP at 5 V –0.5 –0.8 –0.5 –0.8 mA
Hihg-level output voltage VFB, at 2.3 V, RL = 15 kΩ to GND 5 6 5 6 V
Low-level output voltage VFB, at 2.7 V, RL = 15 kΩ to GND 0.7 1.1 0.7 1.1 V
Current-sense Section
Voltage amplification See(4)(5) 2.85 3 3.13 2.85 3 3.15 V/V
Current-sense comparator threshold COMP at 5 V, see(4) 0.9 1 1.1 0.9 1 1.1 V
Supply-voltage rejection ratio VCC = 12 V to 25 V, see(4) 70 70 dB
Input bias current –2 –10 –2 –10 µA
Delay time to output 150 300 150 300 ns
Output Section
High-level output voltage IOH = –20 mA 13 13.5 13 13.5 V
IOH = –200 mA 12 13.5 13 13.5
Low-level output voltage IOH = 20 mA 0.1 0.4 0.1 0.4 V
IOH = 200 mA 1.5 2.2 1.5 2.2
Rise time CL = 1 nF, TA = 25°C 50 150 50 150 ns
fall time CL = 1 nF, TA = 25°C 50 150 50 150 ns
Undervoltage-Lockout Section
Start threshold voltage TLx842, TLx844 15 16 17 14.5 16 17.5 V
TLx843, TLx845 7.8 8.4 9 7.8 8.4 9
Minimum operating voltage after startup TLx842, TLx844 9 10 11 8.5 10 11.5 V
TLx843, TLx845 7 7.6 8.2 7 7.6 8.02
Pulse-Width-Modulator Section
Maximum duty cycle TLx842, TLx843 95% 97% 100% 95% 97% 100%
TLx844, TLx845 46% 48% 50% 46% 48% 50%
Minimum duty cycle 0% 0%
Supply Voltage
Start-up current 0.5 1 0.5 1 mA
Operating supply current VFB and ISENSE at 0 V 11 17 11 17 mA
Limiting voltage ICC = 25 mA 34 34 V
(1) All typical values are at TA = 25°C.
(2) Adjust VCC above the start threshold before setting it to 15 V.
(3) Output frequency equals oscillator frequency for the TLx842 and TLx843. Output frequency is one-half the oscillator frequency for the TLx844 and TLx845.
(4) These parameters are measured at the trip point of the latch, with VFB at 0 V.
(5) Voltage amplification is measured between ISENSE and COMP, with the input changing from 0 V to 0.8 V.

6.6 Typical Characteristics

TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D001_SLVS038.gif Figure 1. Oscillator Discharge Current
vs
Temperature for VIN = 15 V and VOSC = 2V
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D003_SLVS038.gif Figure 3. Error Amplifier Open-Loop Gain and Phase
vs
Frequency VCC = 15 V, RL = 100 kΩ, and TA = 25 °C
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D005_SLVS038.gif Figure 5. Output Saturation Voltage
vs
Load Current for VCC = 15 V with 5-ms Input Pulses
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D007_SLVS038.gif Figure 7. Reference Voltage vs Source Current
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 apcurve1_slvs038.gif Figure 9. Dead Time vs Timing Capacitance
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D002_SLVS038.gif Figure 2. Current Sense Input Threshold
vs
Error Amplifier Output Voltage for VIN = 15 V
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D004_SLVS038.gif Figure 4. Max Output Duty Cycle
vs
Timing Resistor for VCC = 15, CT = 3.3 nF, TA = 25 °C
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D006_SLVS038.gif Figure 6. Reference Short Circuit Current
vs
Temperature for VIN = 15 V
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 D008_SLVS038.gif Figure 8. Reference Voltage vs Temperature
TL2842 TL2843 TL2844 TL2845 TL3842 TL3843 TL3844 TL3845 apcurve2_slvs038.gif Figure 10. Timing Resistance vs Frequency