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Application Note 1919
ISL8115DEMO1Z Synchronous Buck Converter User
Guide
Introduction
The ISL8115DEMO1Z is a compact reference design
Synchronous Buck Converter (28.19mmx16.89mm)
implementing Intersil’s wide input range PWM controller
ISL8115. Utilizing voltage mode control with input
feed-forward, the ISL8115DEMO1Z maintains a constant loop
gain for optimal transient response, especially for applications
with a wide input voltage range. For a more detailed
description of the ISL8115 functionality, refer to the ISL8115
datasheet.
This user guide includes the test setup, typical performance
waveforms, schematic, layout and bill of materials (BOM).
Specifications
Key Features
•Small, compact design
• Fast transient response
- Voltage-mode PWM leading-edge modulation with
nonlinear control
-Input voltage feed-forward
• Integrated 5V high speed 4A MOSFET gate drivers
- Internal bootstrap diode
• Oscillator programmable from 150kHz to 1.5MHz
- Frequency synchronization to external clock signal
• Diode emulation mode for light load efficiency improvement
• Output OVP/UVP; OCP and OTP
•Adjustable soft-start
• Prebias start-up function
• Excellent output voltage regulation
- 0.6V ±1.0% internal reference (-40°C~+125°C)
- 0.6V ±0.7% internal reference (-40°C~+105°C)
- Differential voltage sensing
References
•ISL8115 datasheet
Recommended Equipment
• Input power source up to 36V supply voltage with 125W
power supply ability
• Electronic load with 100W power sinking ability
• Voltmeters and ammeters
• 100MHz quad-trace oscilloscope
TABLE 1. DEMONSTRATION BOARD ELECTRICAL SPECIFICATIONS
SPEC DESCRIPTION MIN TYP MAX UNIT
VIN Input voltage range 16 24 36 V
VOUT Output voltage 5 V
IOUT Output rated current 10 A
IOC Overcurrent threshold 13 A
fsw Switching frequency 600 kHz
Input UVP Rising threshold 15 V
Falling threshold 14.2 V
ηEfficiency at 24V input full
load (10A)
90.12 %
FIGURE 1. ISL8115DEMO1Z DEMONSTRATION BOARD
Ordering Information
PART NUMBER DESCRIPTION
ISL8115DEMO1Z Demonstration Board for ISL8115
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 |Copyright Intersil Americas LLC 2014, 2015. All Rights Reserved
Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
March 11, 2015
AN1919.2