BD9845FV Datasheet, PDF (2/16 Pages) Rohm – Single/Dual-output High-frequency Step-down Switching Regulator(Controller type)

BD9845FV
Technical Note
●Electric characteristics (Ta=25C, VCC=6V unless otherwise specified)
Item
Symbol
Standard value
Min. Typ. Max.
Unit
Condition
[VREF output unit]
Output voltage
VREF
2.450 2.500 2.550 V IO=0.1 mA
Input stability
Line reg. －
1
10 mV Vcc=3.6 V→35 V
Load stability
Load reg. －
2
10 mV IO=0.1 mA→2 mA
Current capacity
IOMAX
2
13
－
mA VREF=(typ.)×0.95
[Triangular wave oscillator]
Oscillation frequency
FOSC
95
106 117 kHz CCP=1800 pF
Frequency fluctuation
FDV
－
0
1
% Vcc=3.6 V→35 V
[Soft start unit]
SS source current
ISSSO
1.4
2
2.6 µA SS=0.5 V
SS sink current
ISSSI
5
12
－ mA SS=0.5 V
[Pause period adjusting circuit]
DT input bias current
IDT
－
0.1
1
µA DT=1.75 V
DT sink current
IDTSI
1
3.3
－ mA DT=1.75 V, (OCP+)-(OCP-)=0.5 V
[Low input malfunction preventing circuit]
Threshold voltage
VUTH
3.0
3.2
3.4
V Vcc start detection
Hysteresis
VUHYS
－
0.15 0.25 V
[Error amplifier]
Non-inverting input reference voltage
VINV
0.99
1
1.01 V INV=FB
Reference voltage supply fluctuation dVinv
－
1
6
mV Vcc=3.6 V→35 V
INV input bias current
IIB
－
0
1
µA INV=1 V
Open gain
AV
65
85
－
dB
Max output voltage
VFBH
2.30
－ VREF V
Min output voltage
VFBL
－
0.6
1.3
V
Output sink current
IFBSI
0.5
1.5
－ mA FB=1.25 V, INV=1.5 V
Output source current
IFBSO
50
105
－
µA FB=1.25 V, INV=0.5 V
[PWM comparator]
Input threshold voltage(fosc=100kHz)
Vt0
Vt100
1.4
1.5
1.6
V On duty 0%
1.9
2
2.1
V On duty 100%
[Output unit]
Output ON resistance H
RONH
－
4.0
10
Ω RONH=(VCC -OUT)/ Iout, Iout=0.1 A
Output ON resistance L
RONL
－
3.3
10
Ω RONL=(OUT-C5 V)/ Iout, Iout=0.1 A
C5V clamp voltage
VCLMP
4.5
5
5.5
V VCLMP= VCC-C5V , VCC ＞7 V
[Overcurrent protection circuit]
Overcurrent detection threshold voltage VOCPTH 0.04 0.05 0.06 V Voltage between(OCP+) and (OCP-)
OCP-input bias current
IOCP-
－
0.1
10
µA OCP+= VCC, OCP-= VCC-0.5 V
Overcurrent detection delay time
tdocpth
－
200 400 ns OCP-= VCC→VCC-0.2 V
Overcurrent detection minimum
retention time
tdocpre
0.8
1.6
－
ms OCP-= VCC-0.2 V→VCC
[Standby changeover unit]
STB flow-in current
ISTB
-
55
100 µA STB=6V
Standby mode setting range
VSTBL
0
-
0.5
V
Active (master) mode setting range
VSTBH
3.0
-
VCC
V
SEL flow-in current
ISEL
-
15
30 µA SEL=2.5V
Master mode setting range
VSELL
0
-
0.5
V
Slave mode setting range
VSELH
2.0
-
VCC
V
[Device overall]
Standby current
ICCS
－
0
1
µA STB=0 V
Average power consumption
ICCA
1
2.4
4
mA INV=0 V, FB=H, DT=1.75 V
* Radiation resistance design is not applied.
www.rohm.com
© 2009 ROHM Co., Ltd. All rights reserved.
2/15
2009.05 - Rev.A