bd9575fv-e2 ROHM Co. Ltd., bd9575fv-e2 Datasheet - Page 10

• Manufacturer Part Number: bd9575fv-e2
• Description: Switching Regulators Ddr-sdram Cores
• Manufacturer: ROHM Co. Ltd.

●Timing Chart
© 2009 ROHM Co., Ltd. All rights reserved.
BD9575FV
www.rohm.com
VOUT
EN/UVLO
・Soft Start Function
・Timer Latch Type Short Circuit Protection
・Over Voltage Protection
HG
LG
V
OUT
EN
SS
V
IIN
SCP
OUT
T
T
SS
SCP
REF×0.7
REF×1.2
Switching
10/20
Soft start is exercised with the EN pin set high. Current
control takes effect at startup, enabling a moderate
output voltage “ramping start.” Soft start timing and
incoming current are calculated with formulas (2) and
(3) below.
Soft start time
Incoming current
(Css: Soft start capacitor; Co: Output capacitor)
Short protection kicks in when output falls to or below
REF X 0.7. When the programmed time period elapses,
output is latched OFF to prevent destruction of the IC.
Output voltage can be restored either by reconnecting
the EN pin or disabling UVLO. Short circuit protection
time is programmed using formula (4) below.
Short protection time setting
Tss=
I
Tscp=
IN
=
REF×Css
Co×V
1.25(V)×C
2μA(typ)
Tss
2μA(typ)
OUT
SCP
[sec]
[A]
・・・(2)
・・・(3)
[sec] ・・・(4)
Technical Note
2009.04 - Rev.B