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dc1999af

DEMO MANUAL DC1999A

DESCRIPTION

LTC3111EDHD

15V, 1.5A Synchronous

Buck-Boost DC/DC Converter

Demonstration circuit 1999A is a fixed frequency syn-

chronous buck-boost converter with an extended input

and output range. The unique 4-switch, single inductor

architecture provides low noise and seamless operation

from input voltages above, below, or equal to the output

voltage.

operation,andaneasilysynchronizableoscillator.Jumper

JP1 is provided to enable the converter. The demo board

is configured for 800kHz. A jumper, JP2, is provided to

select PWM, or Burst Mode operation. A clock signal can

also be applied to JP2 if synchronization is desired.

The LTC3111 operates with a 2.5V to 15V input voltage

from 2.5V to 15V and an output current up to 1.5A. For

L

, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks

of Linear Technology Corporation. All other trademarks are the property of their respective

owners.

PERFORMANCE SUMMARY

Typical demo board efficiency is shown in Figure 2 for

several loads. The demo board has the provision to set an

accuraterunthreshold.ConsulttheLTC3111datasheetfor

more information. The transient response of the converter

to a 100mA to 600mA transient at input voltages of 3.5V

and 12V are presented in Figures 3 and 4.

The LTC3111 data sheet has detailed information about

the operation, specifications, and applications of the part.

The data sheet should be read in conjunction with this

Quick Start Guide.

Design files for this circuit board are available at

http://www.linear.com/demo

INPUT VOLTAGE RANGE

2.5V to 15V

5V