SNVSC41 November   2023 LMR36500

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD (Commercial) 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 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Enable, Shutdown, and Start-up
      2. 7.3.2 Adjustable Switching Frequency (with RT)
      3. 7.3.3 Power-Good Output Operation
      4. 7.3.4 Internal LDO, VCC UVLO, and VOUT/FB Input
      5. 7.3.5 Bootstrap Voltage and VBOOT-UVLO (BOOT Terminal)
      6. 7.3.6 Output Voltage Selection
      7. 7.3.7 Soft Start and Recovery from Dropout
        1. 7.3.7.1 Soft Start
        2. 7.3.7.2 Recovery from Dropout
      8. 7.3.8 Current Limit and Short Circuit
      9. 7.3.9 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 CCM Mode
        2. 7.4.3.2 AUTO Mode - Light Load Operation
          1. 7.4.3.2.1 Diode Emulation
          2. 7.4.3.2.2 Frequency Reduction
        3. 7.4.3.3 FPWM Mode - Light Load Operation
        4. 7.4.3.4 Minimum On-time Operation
        5. 7.4.3.5 Dropout
  9. 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  Choosing the Switching Frequency
        2. 8.2.2.2  Setting the Output Voltage
          1. 8.2.2.2.1 VOUT / FB for Adjustable Output
        3. 8.2.2.3  Inductor Selection
        4. 8.2.2.4  Output Capacitor Selection
        5. 8.2.2.5  Input Capacitor Selection
        6. 8.2.2.6  CBOOT
        7. 8.2.2.7  VCC
        8. 8.2.2.8  CFF Selection
        9. 8.2.2.9  External UVLO
        10. 8.2.2.10 Maximum Ambient Temperature
      3. 8.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
        1. 8.5.1.1 Ground and Thermal Considerations
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Device Nomenclature
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

6.5 Electrical Characteristics

Limits apply over the recommended operating junction temperature (TJ) range of –40°C to +150°C, unless otherwise stated. Minimum and maximum limits are specified through test, design or statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated, the following conditions apply: VIN = 24 V. (1)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
SUPPLY VOLTAGE (VIN PIN)
VIN_R Minimum operating input voltage (rising) Rising threshold 3.4 3.55 V
VIN_F Minimum operating input voltage (falling) Once operating; Falling threshold 2.45 2.7 V
ISD_13p5 Shutdown quiescent current; measured at VIN pin (2) VEN = 0 V; VIN = 13.5 V 0.5 1.1 µA
ISD_24p0 Shutdown quiescent current; measured at VIN pin (2) VEN = 0 V; VIN = 24 V 1 1.6 µA
IQ_13p5_Fixed Non-switching input current; measured at VIN pin (2) (4) VIN = VEN = 13.5 V; VOUT/FB = 5.25 V,  VRT = 0 V; Fixed output 0.25 0.672 1.05 µA
IQ_13p5_Adj Non-switching input current; measured at VIN pin (2) (4) VIN = VEN = 13.5 V; VFB = 1.05 V, VRT = 0 V; Adjustable output 14 17 23.1 µA
IQ_24p0_Fixed Non-switching input current; measured at VIN pin (2) (4) VIN = VEN = 24 V; VOUT/FB = 5.25 V, VRT = 0 V; Fixed output 0.8 1.2 1.7 µA
IQ_24p0_Adj Non-switching input current; measured at VIN pin (2) (4) VIN = VEN = 24 V; VFB = 1.05 V, VRT = 0 V; Adjustable output 14 18 22
µA
IB_13p5 Current into VOUT/FB pin (not switching) (2) (4) VIN = 13.5 V, VOUT/FB = 5.25 V, VRT = 0 V; Fixed output 14 17 22 µA
IB_24p0 Current into VOUT/FB pin (not switching) (2) (4) VIN = 24 V, VOUT/FB = 5.25 V, VRT = 0 V; Fixed output 14 18 22 µA
ENABLE (EN PIN)
VEN-WAKE Enable wake-up threshold 0.4 V
VEN-VOUT Precision enable high level 1.16 1.263 1.36 V
VEN-HYST Enable threshold hysteresis 0.285 0.35 0.425 V
ILKG-EN Enable input leakage current VEN = 3.3 V 0.2 8 nA
INTERNAL LDO
VCC Internal VCC voltage 3.6 V ≤ VIN ≤ 65 V; Adjustable output option 3.2 3.3 3.4 V
ICC Bias regulator current limit 50 120 mA
VCC-UVLO Internal VCC undervoltage lockout VCC rising undervoltage threshold 3 3.3 3.65 V
VCC-UVLO-HYST Internal VCC undervoltage lockout hysteresis Hysteresis below VCC-UVLO 0.4 0.8 1.2 V
CURRENT LIMITS
ISC-50mA Short circuit high side current limit (3) 50 mA version 65 85 105 mA
ILS-LIMIT-50mA Low side current limit (3) 50 mA version 45 60 70 mA
IPEAK-MIN-50mA Minimum peak inductor current limit (3) PFM Operation, 50 mA version; Duty Cycle = 0% 30 40 50 mA
IZC Zero cross current (3) Auto mode 0 2.5 5 mA
IL-NEG-50mA Sink current limit (negative) (3) FPWM mode -73 -60 -47 mA
POWER GOOD
PG-OV PGOOD upper threshold - rising % of FB (Adjustable output) or % of VOUT/FB (Fixed output) 106 107 110 %
PG-UV PGOOD lower threshold - falling % of FB (Adjustable output) or % of VOUT/FB (Fixed output) 93 94 96.5 %
PG-HYS PGOOD hysteresis - rising/falling  % of FB (Adjustable output) or % of VOUT/FB (Fixed output) 0.8 1.2 1.8 %
VPG-VALID Minimum input voltage for proper PG function 0.7 0.9 2 V
RPG-EN5p0 PGOOD pulldown resistance VEN = 5.0 V, 1 mA pullup current 20 40 70 Ω
RPG-EN0 PGOOD pulldown resistance VEN = 0 V, 1 mA pullup current 15 24 46 Ω
MOSFETS
RDSON-HS High-side MOSFET on-resistance Load = 50 mA (LMR36500 variant) 5 Ω
RDSON-LS Low-side MOSFET on-resistance Load = 50 mA (LMR36500 variant) 3.5 Ω
VBOOT-UVLO BOOT - SW UVLO threshold 2.14 2.3 2.42 V
VOLTAGE FEEDBACK (VOUT/FB PIN)
VOUT Output Voltage Accuracy for fixed VOUT VOUT = 3.3-V, VIN = 3.6 V to 65 V, FPWM  3.24 3.3 3.34 V
VOUT Output Voltage Accuracy for fixed VOUT (4) VOUT = 5-V, VIN = 5.5 V to 65 V, FPWM  4.93 5 5.08 V
VREF Internal reference voltage VIN = 3.6 V to 65 V, FPWM mode 0.985 1 1.01 V
IFB FB input current Adjustable output, FB = 1 V 1 30 nA
SOFT START
tSS Time from first SW pulse to VFB at 90% of VREF VIN ≥ 3.6 V 1.95 2.58 3.2 ms
POWER GOOD
tRESET_FILTER Glitch filter time constant for PG function 15 25 40 µs
tPGOOD_ACT Delay time to PG high signal 1.7 1.956 2.16 ms
PWM LIMITS (SW)
tON-MIN Minimum switch on-time VIN = 24 V, IOUT = 50 mA 35 60 85 ns
OSCILLATOR (RT)
fOSC_2p2MHz Internal oscillator frequency RT = GND 2.1 2.2 2.3 MHz
fOSC_1p0MHz Internal oscillator frequency RT = VCC 0.93 1 1.05 MHz
fADJ_400kHz Accuracy of external frequency, 400 kHz RT = 39.2 kΩ 0.34 0.4 0.46 MHz
(1) MIN and MAX limits are 100% production tested at 25ºC. Limits over the operating temperature range verified through correlation using Statistical Quality Control (SQC) methods. Limits are used to calculate Average Outgoing Quality Level (AOQL).
(2) This is the current used by the device open loop. It does not represent the total input current of the system when in regulation.
(3) The current limit values in this table are tested, open loop, in production. 
(4) Preview.