Datasheet
Table Of Contents
- FEATURES
- APPLICATIONS
- CONTENTS
- DESCRIPTION
- DEVICE RATINGS
- ABSOLUTE MAXIMUM RATINGS
- RECOMMENDED OPERATING CONDITIONS
- ELECTROSTATIC DISCHARGE (ESD) PROTECTION
- PACKAGE DISSIPATION RATINGS
- ELECTRICAL CHARACTERISTICS
- TYPICAL CHARACTERISTICS
- DEVICE INFORMATION
- BLOCK DIAGRAM
- APPLICATION INFORMATION
- FUNCTIONAL DESCRIPTION
- Voltage Reference
- Oscillator
- Input Undervoltage Lockout (UVLO) and Startup
- Enable and Timed Turn On of the Outputs
- Output Voltage Sequencing
- Soft Start
- Output Voltage Regulation
- Feedback Loop and Inductor-Capacitor (L-C) Filter Selection
- Inductor-Capacitor (L-C) Selection
- Maximum Output Capacitance
- Minimum Output Capacitance
- Modifying The Feedback Loop
- Example: TPS54386 Buck Converter Operating at 12-V Input, 3.3-V Output and 400-mA(P-P) Ripple Current
- Bootstrap for the N-Channel MOSFET
- Light Load Operation
- SW Node Ringing
- Output Overload Protection
- Operating Near Maximum Duty Cycle
- Dual Supply Operation
- Cascading Supply Operation
- Multiphase Operation
- Bypass and FIltering
- Over-Temperature Protection and Junction Temperature Rise
- Power Derating
- PowerPAD Package
- PCB Layout Guidelines
- FUNCTIONAL DESCRIPTION
- DESIGN EXAMPLES
- ADDITIONAL REFERENCES
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f
f
ZERO(desired)
ESR(zero)
R2
R3
1
=
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(4)
TPS54383 , , TPS54386
SLUS774B – AUGUST 2007 – REVISED OCTOBER 2007
The value of the resistor is calculated using a ratio of impedances to match the ratio of ESR zero frequency to
the desired zero frequency.
where:
• f
ESR(zero)
is the ESR zero frequency of the output capacitor.
• f
ZERO(desired)
is the desired frequency of the zero added to the feedback. This frequency should be placed
between 20 kHz and 60 kHz to ensure good loop stability.
Copyright © 2007, Texas Instruments Incorporated Submit Documentation Feedback 21
Product Folder Link(s): TPS54383 TPS54386