L6725_07 Datasheet, PDF (22/32 Pages) STMicroelectronics – Voltage mode PWM controller with bootstrap anti-discharging system

Demoboard
7 Demoboard
L6725 - L6725A
7.1 20A board description
L6725 demoboard realizes in a four layer PCB a step-down DC/DC converter and shows the
operation of the device in a general purpose application. The input voltage can range from 4.5V
to 14V and the output voltage is at 3.3V. The module can deliver an output current in excess of
20A. The switching frequency is set at 250kHz (controller free-running FBSWB) but it can be
set to 500kHz acting on the EAREF pin.
Figure 16. Demoboard schematic
VIN
J1
GIN
EXT REF
VCC
R5
R6
C8
D1
R9
C10
VCCDR
BOOT
OCH
11
EAREF
J2
3
8
5
C5
R8
C7
VCC
12
15
GND
U1
L6725
C9
C11
HGATE
7
6 ^PHASE
LGATE
10
9 ^PGND
R11
Q4-6
R10
D3
Q1-3
C12-C13
L1
R12
C15
C16-C19
VOUT
GOUT
SS
2
C4
4
OCL
R7
1
COMP
16
VFB
C2 R4
C3
R2
R3
R1
C1
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