IRDC3810 International Rectifier, IRDC3810 Datasheet - Page 3

• Manufacturer Part Number: IRDC3810
• Description: BOARD EVAL SYNC BUCK CONVERTER
• Manufacturer: International Rectifier

LAYOUT
The PCB is a 4-layer board. All of layers are 2 Oz. copper. The IR3810 SupIRBuck and all of the
passive components are mounted on the top side of the board.
Power supply decoupling capacitors, the charge-pump capacitor and feedback components are located
close to IR3810. The feedback resistors are connected to the output voltage at the point of regulation
and are located close to the SupIRBuck.
To improve efficiency, the circuit board is designed to minimize the length of the on-board power ground
current path.
CONNECTIONS and OPERATING INSTRUCTIONS
A well regulated +12V input supply should be connected to VIN+ and VIN-. A maximum 12A 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.
IR3810 has two input supplies, one for biasing (Vcc) and the other as input voltage (Vin). These inputs are
connected on the board with a zero ohm resistor (R15). Separate supplies can be applied to these inputs.
Vcc input cannot be connected unless R15 is removed.
and it would be connected to Vcc+ and Vcc-.
Vp pin is connected to the internal reference (Vref) via R14 as the default configuration. External input can
be applied to Vp.
external tracking source should be applied between Vp_Ext and Agnd.
selected to provide the desired ratio between the output voltage and the tracking input. For proper operation
of IR3810, the voltage at Vp pin should be kept between 0.2V to 1.0V and it should be applied whenever
the voltage at Soft-Start pin is greater than 1V.
Rev 0.0
03/14/2008
For tacking applications, R14 should be removed, R17 should be inserted, and the
Connection
VIN+
VIN-
Vcc+
Vcc-
VOUT-
VOUT+
Vp_Ext
Agnd
Table I. Connections
Signal Name
V
Ground of V
Optional Vcc input
Ground for optional Vcc input
Ground of V
V
Optional Tracking input
Analog (Signal) Ground
in
out
(+12V)
Vcc input should be a well regulated 5V-12V supply
in
out
The value of R17 and R28 can be
IRDC3810
3