1.5 A Switch-Mode Power
Supply with Linear Regulator
The 34701 provides the means to efficiently supply the Freescale
Power QUICC™ I, II, and other families of Freescale
microprocessors and DSPs. The 34701 incorporates a high-
performance switching regulator, providing the direct supply for the
microprocessor’s core, and a low dropout (LDO) linear regulator
control circuit providing the microprocessor I/O and bus voltage.
The switching regulator is a high-efficiency synchronous buck
regulator with integrated N-channel power MOSFETs to provide
protection features and to allow space-efficient, compact design.
The 34701 incorporates many advanced features; e.g., precisely
maintained up/down power sequencing, ensuring the proper
operation and protection of the CPU and power system.
• Operating Voltage from 2.8 V to 6.0 V
• High-Accuracy Output Voltages
• Fast Transient Response
• Switcher Output Current Up to 1.5 A
• Undervoltage Lockout and Overcurrent Protection
• Enable Inputs and Programmable Watchdog Timer
• Voltage Margining via I2C™ Bus
• Reset with Programmable Power-ON Delay
• Pb-Free Packaging Designated by Suffix Code EK
I2C is a trademark of Philips Corporation.
Rev 4.0, 05/2005
EK (Pb-FREE) SUFFIX
-40 to 85°C
2.8 V to 6.0 V Input
0.8 V to VIN -
0.8 V to VIN -
Figure 1. 34701 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., 2005. All rights reserved.