bd95710muv-e2 ROHM Co. Ltd., bd95710muv-e2 Datasheet - Page 6

• Manufacturer Part Number: bd95710muv-e2
• Description: 2phase Switching Regulator Controllers Graphic Card
• Manufacturer: ROHM Co. Ltd.

●Explanation of Operation
H
(Normal operation)
Phase PHASEitch function
REFIN/EN
VIN_EXT
© 2009 ROHM Co., Ltd. All rights reserved.
BD95710MUV
www.rohm.com
3
BUSEN
UGAT
Reg
REFIN/
UGAT
UGAT
UGA
VOUT
The BD95710MUV is a synchronous buck regulator controller incorporating ROHM’s proprietary H
control system. When V
interval. Thus, it serves to improve the regulator’s transient response.
The IC normally operates dual-phase mode, but when the input voltage on the VIN_EXT pin is cut off, the IC latches into
single-phase mode. The IC will remain latched in this mode (even if a voltage is reintroduced onto the VIN_EXT pin) until
the voltage is cycled on any of the EN, VCC or BUSEN pins. It will then return to two-phase mode.
FB
TM
EN
control
dual-phase
OUT
drops due to a rapid load change, the system quickly restores V
T
2T
Single-phase
6/20
Stand-by
When FB pin voltage (Vout) falls to a threshold voltage
REFIN/EN, the drop is detected, activating the H
CONTROLLA system.
UGATE ONTIME is determined with the formula above.
LG outputs until the status of VOUT is lower than REF
after the status of UG is off.
T
ON
=
REFIN/EN
VIN
dual-phase
×
1
f
[sec]・・・(1)
OUT
by extending the T
3
Reg
TM
Technical Note
2009.04 - Rev.B
CONTROLLA
ON
3
Reg
time
TM