SLVSEW2A September   2020  – August 2021 TPS54618C-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Timing Requirements
    7. 6.7 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  Fixed Frequency PWM Control
      2. 7.3.2  Slope Compensation and Output Current
      3. 7.3.3  Bootstrap Voltage (Boot) and Low Dropout Operation
      4. 7.3.4  Error Amplifier
      5. 7.3.5  Voltage Reference
      6. 7.3.6  Adjusting the Output Voltage
      7. 7.3.7  Enable and Adjusting Undervoltage Lockout
      8. 7.3.8  Soft-Start Pin
      9. 7.3.9  Sequencing
      10. 7.3.10 Constant Switching Frequency and Timing Resistor (RT/CLK Pin)
      11. 7.3.11 Overcurrent Protection
      12. 7.3.12 Frequency Shift
      13. 7.3.13 Reverse Overcurrent Protection
      14. 7.3.14 Synchronize Using the RT/CLK Pin
      15. 7.3.15 Power Good (PWRGD Pin)
      16. 7.3.16 Overvoltage Transient Protection
      17. 7.3.17 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Simple Small Signal Model for Peak Current Mode Control
      2. 7.4.2 Small Signal Model for Frequency Compensation
  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 Step One: Select the Switching Frequency
        2. 8.2.2.2 Step Two: Select the Output Inductor
        3. 8.2.2.3 Step Three: Choose the Output Capacitor
        4. 8.2.2.4 Step Four: Select the Input Capacitor
        5. 8.2.2.5 Step Five: Choose the Soft-Start Capacitor
        6. 8.2.2.6 Step Six: Select the Bootstrap Capacitor
        7. 8.2.2.7 Step Eight: Select Output Voltage and Feedback Resistors
          1. 8.2.2.7.1 Output Voltage Limitations
        8. 8.2.2.8 Step Nine: Select Loop Compensation Components
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Power Dissipation Estimate
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Developmental Support
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6.5 Electrical Characteristics

at TJ = –40°C to +125°C, VIN = 2.95 to 6 V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY VOLTAGE (VIN PIN)
Operating input voltage 2.95 6 V
Internal undervoltage lockout threshold VIN UVLO STOP 2.28 2.5 V
VIN UVLO START 2.45 2.6
Shutdown supply current EN = 0 V, 25°C, 2.95 V ≤ VIN ≤ 6 V 5.5 15 μA
Quiescent current, IQ VSENSE = 0.9 V, VIN = 5 V, 25°C, RT = 400 kΩ 515 650 μA
ENABLE AND UVLO (EN PIN)
Enable threshold Rising 1.25 V
Falling 1.18
Input current Enable threshold + 50 mV –3.5 μA
Enable threshold – 50 mV –1.9
VOLTAGE REFERENCE (VSENSE PIN)
Voltage reference 2.95 V ≤ VIN ≤ 6 V, –40°C <TJ < 150°C 0.791 0.799 0.807 V
MOSFET
High-side switch resistance BOOT-PH = 5 V 12 25 mΩ
BOOT-PH = 2.95 V 16 33
Low-side switch resistance VIN = 5 V 13 25 mΩ
VIN = 2.95 V 17 33
ERROR AMPLIFIER
Input current 2 nA
Error amplifier transconductance (gm) –2 μA < I(COMP) < 2 μA, V(COMP) = 1 V 245 μmhos
Error amplifier transconductance (gm)
during slow start		 –2 μA < I(COMP) < 2 μA, V(COMP) = 1 V,
VSENSE = 0.4 V		 79 μmhos
Error amplifier source/sink V(COMP) = 1 V, 100-mV overdrive ±20 μA
COMP to Iswitch gm 25 A/V
CURRENT LIMIT
Current limit threshold VIN = 6 V, 25°C < TJ < 150°C 7.46 10.6 15.3 A
VIN = 2.95 V, 25°C < TJ < 150°C 7.68 10.2 13.5
THERMAL SHUTDOWN
Thermal shutdown 168 °C
Hysteresis 20 °C
BOOT (BOOT PIN)
BOOT charge resistance VIN = 5 V 16 Ω
BOOT-PH UVLO VIN= 2.95 V 2.1 V
SLOW-START AND TRACKING (SS/TR PIN)
Charge current V(SS/TR) = 0.4 V 2 μA
SS/TR to VSENSE matching V(SS/TR) = 0.4 V 54 mV
SS/TR to reference crossover 98% normal 1.1 V
SS/TR discharge voltage (overload) VSENSE = 0 V 61 mV
SS/TR discharge current (overload) VSENSE = 0 V, V(SS/TR) = 0.4 V 350 µA
SS discharge current (UVLO, EN, Thermal fault) VIN = 5 V, V(SS) = 0.5 V 1.9 mA
POWER GOOD (PWRGD PIN)
VSENSE threshold VSENSE falling (Fault) 91% Vre
VSENSE rising (Good) 93%
VSENSE rising (Fault) 109%
VSENSE falling (Good) 107%
Hysteresis VSENSE falling 2% Vref
Output high leakage VSENSE = VREF, V(PWRGD) = 5.5 V 7 nA
ON-resistance 56 100 Ω
Output low I(PWRGD) = 3 mA 0.2 0.3 V
Minimum VIN for valid output V(PWRGD) < 0.5 V at 100 μA 0.65 1.5 V