XRP7664-65-74-75
2A/3A 18V Synchronous Step-Down Regulator, Constant frequency
(XRP7664-65), Light-Load efficiency (XRP7674-75)
August 2014
Rev. 2.0.0
Exar Corporation
www.exar.com
48720 Kato Road, Fremont CA 94538, USA
Tel. +1 510 668-7000 – Fax. +1 510 668-7001
GENERAL DESCRIPTION
The EXAR XRP76XX Evaluation kit is a fully
assembled and tested surface-mount PCB that
demonstrates
the
XRP7664,
XRP7665,
XRP7674 and XRP7675 synchronous buck
regulators.
The
current-mode
switching
regulator generates a preset 3.3V output with
a load of up to 2A (XRP7664, XRP7674) and
3A (XRP7665, XRP7675).
The EVB kit requires a single input voltage VIN
source if EN is tied to VIN via jumper J1
(default setting as supplied from EXAR). If J1
is set to EN=EXT position then a logic-level
signal is required at EN pin in order to turn the
regulator on and off.
STANDARD CONFIGURATION
The
XRP76XXEVB
evaluation
board
is
configured to operate under the following
conditions and parameters:
•
Input voltage range:
4.5V - 18V
•
Output voltage range:
3.3V
•
Output current/load range:
0 – 2A/3A
EVALUATION BOARD MANUAL
FEATURES
•
2A/3A Continuous Output Current
•
4.5V to 18V Wide Input Voltage
•
PWM Current-Mode Control
•
Adjustable Output Voltage
−
2% Accuracy
•
Programmable Soft-Start and Enable
Function
•
Constant frequency (XRP7664-65)
•
Light-load efficiency (XRP7674-75)
•
Built-in Thermal, Over Current, UVLO
and Output Over-Voltage Protections
•
RoHS Compliant “Green”/Halogen Free
8-Pin Exposed Pad SOIC Package
EVALUATION BOARD SCHEMATICS
Fig. 1: XRP76XX Evaluation Board Schematics
C4
22uF
CSS
0.1uF
CBS
10nF
CC
nF
RC
k
CC1
DNP
R4 100k
J1
1
2
3
FB
C2
DNP
C3
22uF
GND
VIN
VOUT
GND
EN
1
SW
1
U1
XRP76XX
BS
1
IN
2
SW
3
GND
4
FB
5
COMP
6
EN
7
SS
8
L1
uH
R1
26.1k
R2
10k
C1
uF
EN=EXT
EN=VIN
SW
SW
FB
