Analog Devices LT3845AEFE | Demoboard DC1619A

Description

Demonstration Circuit 1619A is a 100kHz to 500kHz programmable frequency, high voltage, current mode DC/DC step-down converter featuring the LT®3845A. The operating frequency can be synchronized up to 600kHz. This demo board is designed for 12V up to 10A (120W) output from a 16V to 60V input. A soft-start feature controls the output voltage slew rate at start-up, reducing current surges and voltage overshoots. The modes of operation (Burst Mode®, discontinuous current mode and continuouscurrent mode) are jumper selectable. Both Burst Mode operation and discontinuous current mode increase the efficiency at light loads. Continuous current mode will maintain a constant switching frequency regardless of the load current.

An optional boost bias circuit is provided on the bottom side of the board for back-driving the LT3845A internal regulator from the output voltage. Customers may want to use this optional circuit with modified applicationsthat have relatively high input voltages and low (~3.3V) output voltages. In such applications, this optional circuit can increase the overall efficiency by reducing the power loss in the LT3845A. The demonstration board has theoption of doubling the number of switching MOSFETs to facilitate higher output current. This board is suitable for a wide range of industrial control systems and telecom power supplies.

The LT3845A data sheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with this quick start guide for demo circuit 1619A.

Note: It is best to ground the SYNC pin if the SYNC function is not being used.

More information

• Datasheet
• IC product information