SNVSAE4C July   2015  – October 2018

PRODUCTION DATA.

1. Features
2. Applications
3. Description
1.     Device Images
4. Revision History
5. Pin Configuration and Functions
6. Specifications
7. Detailed Description
1. 7.1 Overview
2. 7.2 Functional Block Diagram
3. 7.3 Feature Description
4. 7.4 Device Functional Modes
8. Application and Implementation
1. 8.1 Application Information
2. 8.2 Typical Applications
1. 8.2.1 LM5160-Q1 Synchronous Buck (10-V to 60-V Input, 5-V Output, 1.5-A Load)
2. 8.2.2 LM5160-Q1 Isolated Fly-Buck (18-V to 32-V Input, 12-V, 4.5-W Isolated Output)
3. 8.3 Do's and Don'ts
9. Power Supply Recommendations
10. 10Layout
11. 11Device and Documentation Support
1. 11.1 Device Support
2. 11.2 Documentation Support
4. 11.4 Community Resources
6. 11.6 Electrostatic Discharge Caution
7. 11.7 Glossary
12. 12Mechanical, Packaging, and Orderable Information

• PWP|14
• PWP|14

#### 8.2.2.2.4 Output Capacitor - COUT2

The Fly-Buck output capacitor conducts higher ripple current than a buck converter output capacitor. Calculate the capacitive ripple for the isolated output capacitor based on the time the rectifier diode is off. During this time the entire output current is supplied by the output capacitor. Calculate the required capacitance for a worst-case VOUT2 (VOUT(ISO)) ripple voltage using Equation 24.

Equation 24.

where

• ΔVOUT2 is the target ripple at the secondary output.

Equation 24 is an approximation and ignores the ripple components associated with ESR and ESL of the output capacitor. For a ΔVOUT2 = 100 mV, Equation 24 requires COUT2 = 6.5 µF. When selecting a ceramic capacitor, consider its voltage coefficient to ensure sufficient capacitance at the output voltage operating point.