1
Application Note 1587
ISL8022EVAL2Z Dual 2A/1.7A Low Quiescent
Current 2.25MHz High Efficiency Synchronous Buck
Regulator
Description
The ISL8022EVAL2Z kit is intended for use by
individuals with requirements for Point-of-Load
applications sourcing from 2.8V to 5.5V. The
ISL8022EVAL2Z evaluation board is used to demonstrate
the performance of the ISL8022 low quiescent current
mode converter.
The ISL8022 is offered in a 4mmx3mm 12 Ld DFN
package with 1mm maximum height. The complete
converter occupies less than 0.175in
2
area.
Key Features
• Dual 2A/1.7A High Efficiency Synchronous Buck
Regulator with up to 97% Efficiency
• 180° Out-of-Phase
• Power-Goods (PG) Output with 1ms Delay
• 2.8V to 5.5V Supply Voltage
• 3% Output Accuracy Over-temperature/Load/Line
• Start-up with Pre-biased Output
• 40µA Quiescent Supply Current in PFM Mode
• Selectable Forced PWM Mode and PFM Mode
• External Synchronization up to 8MHz
• Typical 6.5µA Logic Controlled Shutdown Current
• 100% Maximum Duty Cycle for Lowest Dropout
• Internal Current Mode Compensation
• Peak Current Limiting, Hiccup Mode Short Circuit
Protection and Over-temperature Protection
• Negative Current Detection and Protection
Recommended Equipment
The following materials are recommended to perform
testing:
• 0V to 10V Power Supply with at least 3A source
current capability or 5V battery
• Electronic Loads capable of sinking current up to 3A
• Digital Multimeters (DMMs)
• 100MHz quad-trace oscilloscope
•Signal generator
Quick Setup Guide
1. Ensure that the circuit is correctly connected to the
supply and loads prior to applying any power.
2. Connect the bias supply to VIN, the plus terminal to
VIN and the negative return to P1.
3. Turn on the power supply.
4. Verify the output voltage is 2.5V for V
OUT1
and 1.8V
for V
OUT2.
TABLE 1. BILL OF MATERIALS
REFERENCE
DESIGNATOR DESCRIPTION MFR MFR PART
PWB-PCB,
ISL8022EVAL2Z,
REVA, ROHS
TBD ISL8022EVAL2ZREVAPCB
C2, C4 CAP, SMD, 0805,
22µF, 6.3V, 20%,
X5R, ROHS
TDK C2012X5R0J226M
C1, C8 CAPACITOR,
SMD, 0805,
10µF, 6.3V, 10%,
X5R
MURATA GRM21BR60J106KE01L
C6, C7 CAP, SMD, 0805,
DNP-PLACE
HOLDER, ROHS
C3, C5 CAP-RF HIQ,
SMD, 0402,
10pF, 50V, 5%,
COG, ROHS
JOHANSON
TECH.
500R07S100JV4T
L1, L2 COIL-PWR
INDUCTOR, WW,
SMD, 4mm,
1.2µH, 30%,
2.7A, ROHS
TDK VLCF4028T-1R2N2R7-2
U1 IC-2A/1.7A
BUCK
REGULATOR,
12P, DFN, 4X3,
ROHS
INTERSIL ISL8022IRZ
R1, R3, R6 RES, SMD, 0402,
100k, 1/16W,
1%, TF, ROHS
PANASONIC ERJ2RKF1003
R5 RES, SMD, 0402,
200k, 1/16W,
1%, TF, ROHS
ROHM MCR01MZPF2003
YAGEO RC0402FR-07200KL
VISHAY/
DALE
CRCW0402200KFKED
VENKEL CR0402-16W-2003FT
R2 RES, SMD, 0402,
316k, 1/16W,
1%, TF, ROHS
PANASONIC ERJ-2RKF3163X
VENKEL CR0402-16W-3163FT
R9 RES, SMD, 0402,
D N P, D N P, D N P,
TF, ROHS
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
| Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2010. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
August 10, 2010
AN1587.1
Author: Huong Doan
