DC1385A: 1.2V and 1.8V @ 4A, 2.4 ~ 5.5V in, Inductor On-Chip

Summary

Demonstration circuit DC1385A features the LTM®4614EV, the high efficiency, high density power module with dual 4A switch mode outputs. Derating is necessary for certain VIN, VOUT, and thermal conditions. In the default configuration, the two outputs share the same input supply, however each regulator may have its own input supply simply by removing a resistor.

By enabling the tracking feature, the outputs coincidentally follow another supply rail. The LTM4614 data sheet must be read in conjunction with this demo board prior to working on or modifying demo circuit DC1477A.

The LTM4614 supports output voltages ranging from 0.8V to 5V. The regulator output voltages are set by a single resistor for each output. Only bulk input and output capacitors are needed to complete the design.

Specifications

Manufacturer	Analog Devices Inc.
Category	AC/DC and DC/DC Conversion
Sub-Category	DC/DC SMPS - Multi Output
Eval Board Part Number	DC1385A-ND
Eval Board Supplier	Analog Devices Inc.
Eval Board	Normally In Stock
Topology	Step Down
Outputs and Type	2 Non-Isolated
Voltage Out: Highest Current First	1.2V, 1.8V
Current Out	4A per Channel
Voltage In	2.4 ~ 5.5 V
Efficiency @ Conditions	>83%, 5V in, 1.8V @ 0.4 ~ 4 A >82%, 3.3V in, 1.8V @ 0.2 ~ 4 A >78%, 5V in, 1.2V @ 0.4 ~ 4 A >77%, 3.3V in, 1.2V @ 0.2 ~ 4 A
Voltage Out Range	- Not Given
Features	Internal Inductor Over Current Protection Over Voltage Protection Power Good Output Short Circuit Protection Soft Start Thermal Protection Voltage Tracking
Switching Frequency	1.25 MHz
Standby Current [Typical]	7 µA
Quiescent Current [Typical]	20 µA
Component Count + Extras	15 + 36
Internal Switch	Yes
Design Author	Linear Technology
Application / Target Market	FPGA / DSP / Processors Point of Load (PoL) Telecom
Standby Current [Maximum]	12 µA
Quiescent Current [Maximum]	35 µA
Main I.C. Base Part	LTM4614
Date Created By Author
Date Added To Library	2011-03