IRDC3640

2

A well regulated +12V input supply should be connected to VIN+ and VIN-. A maximum 25A load should be

connected to VOUT+ and VOUT-. The connection diagram is shown in Fig. 1 and inputs and outputs of the

board are listed in Table I.

IR3640 has two input supplies, one for biasing (Vcc) and the other as input voltage (Vin). Separate supplies

should be applied to these inputs. Vcc input should be a well regulated 4.5V-5.5V supply and it would be

connected to Vcc+ and Vcc-.

CONNECTIONS and OPERATING INSTRUCTIONS

LAYOUT

The PCB is a 6-layer board. All of layers are 2 Oz. copper. The IR3640 and other components are

mounted on the top and bottom side of the board.

Power supply decoupling capacitors, the Bootstrap capacitor and feedback components are located

close to IR3640. The feedback resistors are connected to the output voltage at the point of regulation

and are located close to IR3640. To improve efficiency, the circuit board is designed to minimize the

length of the on-board power ground current path.

Table I. Connections

Connection

Signal Name

VIN+

V

VIN-

Ground of V

in

Vcc+

Vcc input

Vcc-

Ground for Vcc input

VOUT+

V

VOUT-

Ground of Vout

Sync

Synchronous input

PGood

Power Good Signal