XRP7708 Datasheet, PDF (1/27 Pages) Exar Corporation – Quad Channel Digital PWM Step Down Controller

February 2010
XRP7708
Quad Channel Digital PWM Step Down Controller
Rev. 1.0.3
GENERAL DESCRIPTION
The XRP7708 is a quad-output pulse-width
modulated (PWM) step-down DC-DC controller
with a built-in LDO for standby power and
GPIOs. The device provides a complete power
management solution in one IC and is fully
programmable via an I²C serial interface.
Independent Digital Pulse Width Modulator
(DPWM) channels regulate output voltages
and provide all required protection functions
such as current limiting and over-voltage
protection.
Each output voltage can be programmed from
0.9V to 5.1V without the need of an external
voltage divider. The wide range of the
programmable DPWM switching frequency
(from 300 KHz to 1.5 MHz) enables the user to
optimize between efficiency and component
size. Input voltage range is from 6.5V to 20V.
Two controllers support a load of up to 5A,
while the other two controllers support up to
8A. I²C bus interface is provided to program
the IC as well as to communicate with the host
for fault reporting and handling, power rail
parameters monitoring, etc.
The device offers a complete solution for soft-
start and soft-stop. The start-up delay and
ramp of each PWM regulator can be
independently controlled. The device can start
up a pre-biased PWM channel without causing
large negative inductor current.
APPLICATIONS
• Multi Channel Programmable
Power Supplies
• Audio-Video Equipments
• Industrial & Telecom Equipments
• Processors & DSPs Based Equipments
FEATURES
• 4 Channel Step Down Controller
− 2 x 5A Channels & 2 x 8A Channels
− Programmable Output Voltage 0.9V-5.1V
− Programmable 1.5MHz DPWM Frequency
• 6.5V-20V Single Input Voltage Range
• Up to 6 reconfigurable GPIO pins
• Fully programmable via I²C interface
• Independent Digital Pulse Width
Modulator (DPWM) channels
• Complete power monitoring and
reporting
• Full On Board Protection
OTP, UVLO, OCP and OVP
• Built-in 3.3V/5V LDO
• Configuration development tools
• Green/Halogen Free 40-pin TQFN
TYPICAL APPLICATION DIAGRAM
Fig. 1: XRP7708 Application Diagram
Exar Corporation
48720 Kato Road, Fremont CA 94538, USA
www.exar.com
Tel. [phone] – Fax. [phone]