SNVSAO4D December   2017  – August 2020 LMZM33602

PRODUCTION DATA  

  1. 1Features
  2. 2Applications
  3. 3Description
  4. 4Revision History
  5. 5Pin Configuration and Functions
    1.     Pin Functions
  6. 6Specifications
    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 Switching Characteristics
    7. 6.7 Typical Characteristics (VIN = 5 V)
    8. 6.8 Typical Characteristics (VIN = 12 V)
    9. 6.9 Typical Characteristics (VIN = 24 V)
  7. 7Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Adjusting the Output Voltage
      2. 7.3.2  Feedforward Capacitor, CFF
      3. 7.3.3  Voltage Dropout
      4. 7.3.4  Switching Frequency (RT)
      5. 7.3.5  Synchronization (SYNC)
      6. 7.3.6  Input Capacitors
      7. 7.3.7  Output Capacitors
      8. 7.3.8  Output On/Off Enable (EN)
      9. 7.3.9  Programmable Undervoltage Lockout (UVLO)
      10. 7.3.10 Power Good (PGOOD)
      11. 7.3.11 Overcurrent Protection (OCP)
      12. 7.3.12 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Active Mode
      2. 7.4.2 Shutdown Mode
  8. 8Application 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 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Output Voltage Setpoint
        3. 8.2.2.3 Feedforward Capacitor (CFF)
        4. 8.2.2.4 Setting the Switching Frequency
        5. 8.2.2.5 Input Capacitors
        6. 8.2.2.6 Output Capacitor Selection
        7. 8.2.2.7 Application Curves
  9. 9Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 Custom Design With WEBENCH® Tools
    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

Electrical Characteristics

Over –40°C to +105°C ambient temperature, VIN = 24 V, VOUT = 5 V, IOUT = IOUT maximum, fsw = 450 kHz (unless otherwise noted); CIN1 = 2 × 4.7-µF, 50-V, 1210 ceramic; CIN2 = 100-µF, 50-V, electrolytic; COUT = 4 × 22-µF, 25-V, 1210 ceramic. Minimum and maximum limits are specified through production test or by design. Typical values represent the most likely parametric norm and are provided for reference only.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
INPUT VOLTAGE (VIN)
VIN Input voltage Over IOUT range 4(1) 36 V
UVLO VIN undervoltage lockout VIN increasing 3.3 3.6 3.9 V
VIN decreasing 3 3.3 3.5 V
ISHDN Shutdown supply current VEN = 0 V, VIN = 12 V 2 4 µA
OUTPUT VOLTAGE (VOUT)
VOUT(ADJ) Output voltage adjust Over IOUT range 1 18 V
VOUT(Ripple) Output voltage ripple 20-MHz bandwidth 10 mV
FEEDBACK
VFB Feedback voltage(2) TA = 25°C, IOUT = 0 A 0.985 1 1.015 V
Over VIN range, –40°C ≤ TJ ≤ 125°C, IOUT = 0 A 0.98 1 1.02 V
Load regulation Over IOUT range, TA = 25°C 0.04%
IFB Feedback leakage current VFB = 1 V 10 nA
CURRENT
IOUT Output current Natural convection, TA = 25°C 0 2 A
Overcurrent threshold 3.6 A
PERFORMANCE
ƞ Efficiency VIN = 24 V,
IOUT = 1 A
VOUT = 12 V, fSW = 900 kHz 94%
VOUT = 5 V, fSW = 450 kHz 90%
VOUT = 3.3 V, fSW = 300 kHz 88%
VIN = 12 V,
IOUT = 1 A
VOUT = 5 V, fSW = 450 kHz 93%
VOUT = 3.3 V, fSW = 300 kHz 91%
VOUT = 2.5 V, fSW = 250 kHz 89%
Transient response 25% to 75% load step
1 A/µs slew rate
Over/undershoot 90 mV
Recovery time 55 µs
SOFT START
TSS Internal soft start time 6 ms
THERMAL
TSHDN Thermal shutdown Shutdown temperature 170 °C
Hysteresis 15 °C
ENABLE (EN)
VEN-H EN rising threshold 1.4 1.55 1.7 V
VEN-HYS EN hysteresis voltage 0.4 V
IEN EN Input leakage current VIN = 4 V to 36 V, VEN = 2 V 10 100 nA
VIN = 4 V to 36 V, VEN = 36 V 1 µA
POWER GOOD (PGOOD)
VPGOOD PGOOD thresholds VOUT rising (good) 92% 94% 96.5%
VOUT rising (fault) 104% 107% 110%
VOUT falling hysteresis 1.5%
Minimum VIN for valid PGOOD 50-μA pullup, VEN = 0 V, TA = 25°C 1.5 V
PGOOD low voltage 0.5-mA pullup, VEN = 0 V 0.4 V
CAPACITANCE
CIN External input capacitance Ceramic type 9.4(3) µF
Non-ceramic type 47(3) µF
COUT External output capacitance min(4) max(5) µF
See Voltage Dropout for information on voltage dropout.
The overall output voltage tolerance will be affected by the tolerance of the external RFBT and RFBB resistors.
A minimum of 9.4 µF (2 × 4.7 µF) ceramic input capacitance is required for proper operation. An additional 47 µF of bulk capacitance is recommended for applications with transient load requirements. See the Input Capacitors section of the datasheet for further guidance.
The minimum amount of required output capacitance varies depending on the output voltage (see Output Capacitor Selection ). A minimum amount of ceramic output capacitance is required. Locate the capacitance close to the device. Adding additional ceramic or non-ceramic capacitance close to the load improves the response of the regulator to load transients.
The maximum allowable output capacitance varies depending on the output voltage (see Output Capacitor Selection ).