Freescale Semiconductor
Advance Information
Document number: MC34712
Rev. 4.0, 5/2007
3.0 A 1.0 MHz Fully Integrated
DDR Switch-Mode Power
Supply
The 34712 is a highly integrated, space efficient, low cost, single
synchronous buck switching regulator with integrated N-channel
power MOSFETs. It is a high performance point-of-load (PoL) power
supply with the ability to track an external reference voltage.
Its high efficient 3.0 A sink and source capability combined with its
voltage tracking/sequencing ability and tight output regulation, makes
it ideal to provide the termination voltage (V
TT
) for modern data buses
such as Double-Data-Rate (DDR) memory buses. It also provides a
buffered output reference voltage (V
REF
) to the memory chipset
The 34712 offers the designer the flexibility of many control,
supervisory, and protection functions to allow for easy implementation
of complex designs. It is housed in a Pb-Free, thermally enhanced,
and space efficient 24-Pin Exposed Pad QFN.
Features
• 45 m
Ω
Integrated N-Channel Power MOSFETs
• Input Voltage Operating Range from 3.0 V to 6.0 V
•
±
1 % Accurate Output Voltage, Ranging from 0.7 V to 1.35 V
•
±
1 % Accurate Buffered Reference Output Voltage
• Programmable Switching Frequency Range from 200 kHz to
1.0 MHz with a default of 1.0 MHz
• Over Current Limit and Short Circuit Protection
• Thermal Shutdown
• Output Overvoltage and Undervoltage Detection
• Active Low Power Good Output Signal
• Active Low Standby and Shutdown Inputs
• Pb-Free Packaging Designated by Suffix Code EP.
V
IN
(3.0V TO 6.0V)
34712
SWITCH-MODE POWER SUPPLY
EP SUFFIX
98ARL10577D
24-PIN QFN
ORDERING INFORMATION
Device
MC34712EP/R2
Temperature
Range (T
A
)
-40 to 85°C
Package
24 QFN
34712
PVIN
V
DDQ
VREFIN
SW
VIN
VDDI
FREQ
GND
SD
VOUT
V
DDQ
MEMORY
BUS
BOOT
V
TT
TERMINATING
RESISTORS
INV
COMP
VREFOUT
PGND
PG
V
IN
DDR MEMORY
CHIPSET
V
REF
DDR MEMORY
CONTROLER
V
DDQ
MCU
STBY
Figure 1. 34712 Simplified Application Diagram
* This document contains certain information on a new product.
Specifications and information herein are subject to change without notice.
© Freescale Semiconductor, Inc., 2007. All rights reserved.