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Single-chip Type with built-in FET Switching Regulator Series
Flexible Step-down
Switching Regulators
with Built-in Power MOSFET
BD9778F, BD9778HFP, BD9001F, BD9781HFP
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© 2010 ROHM Co., Ltd. All rights reserved.
No.10027EBT41
Overview
Features
1)
2)
3)
4)
5)
6)
8)
9)
10)
11)
12)
13)
14)
15)
Minimal external components
Wide input voltage range: 7 V to 35 V (BD9778F/HFP and BD9781HFP), 7 V to 48 V (BD9001F)
Built-in P-ch POWER MOS FET
Output voltage setting enabled with external resistor: 1 to V
IN
Reference voltage accuracy: ±2%
Wide operating temperature range: -40˚C to +125˚C (BD9778F/HFP and BD9781HFP),
-40˚C to +95˚C (BD9001F)
Low dropout: 100% ON Duty cycle
Standby mode supply current: 0 µA (Typ.) (BD9778F/HFP and BD9781HFP), 4 µA (Typ.) (BD9001F)
Oscillation frequency variable with external resistor: 50 to 300 kHz (BD9001F),
50 to 500 kHz (BD9778F/HFP and BD9781HFP)
External synchronization enabled (only on the BD9781HFP)
Soft start function : soft start time fixed to 5 ms (Typ.))
Built-in overcurrent protection circuit
Built-in thermal shutdown protection circuit
High power HRP7 package mounted (BD9778HFP and BD9781HFP)
Compact SOP8 package mounted (BD9778F and BD9001F)
All fields of industrial equipment, such as Flat TV , printer, DVD, car audio, car navigation,
and communication such as ETC, AV, and OA.
Applications
Product lineup
The flexible step-down switching regulator controller is a switching regulator controller designed with a high-withstand-voltage
built-in POWER MOS FET, providing a free setting function of operating frequency with external resistor. This switching regulator
controller features a wide input voltage range (7 V to 35 V or 7 V to 48 V) and operating temperature range (-40˚C to +125˚C or
-40˚C to +95˚C). Furthermore, an external synchronization input pin (BD9781HFP) enables synchronous operation with external
clock.
BD9778F/HFP
2A
7V ~ 35V
50 ~ 500kHz
Not provided
Provided
-
40˚C ~ +125˚C
SOP8 / HRP7
Output current
Input range
Oscillation frequency range
External synchronization
Standby function
Operating temperature
Package
BD9001F
2A
7V ~ 48V
50 ~ 300kHz
Not provided
Provided
-
40˚C ~ +95˚C
SOP8
BD9781HFP
4A
7V ~ 35V
50 ~ 500kHz
Provided
Provided
-
40˚C ~ +125˚C
HRP7
Item
Dec.2015 - Rev.C
2/16
Technical Note
Absolute Maximum Ratings(Ta = 25˚C)
Recommended operating range
Electrical characteristics
*1 Should not exceed Pd-value.
*2 Reduce by 44mW/°C over 25°C, when mounted on 2-layer PCB of 70 X 70 X 1.6 mm3.
(PCB incorporates thermal via. Copper foil area on the front side of PCB: 10.5 X 10.5 mm2. Copper foil area on the reverse side of PCB: 70 X 70 mm2)
*3 Reduce by 5.52 mW/°C over 25°C, when mounted on 2-layer PCB of 70 X 70 X 1.6 mm3.
Output switch pin voltage
Output switch current
BD9778F/HFP,BD9781HFP
BD9778F/HFP,BD9781HFP
BD9778F/HFP, BD9001F
BD9001F
BD9001F
BD9781HFP
HRP7
SOP8
Power dissipation
Parameter Symbol Unit
V
EN/SYNC,VEN
VRT,VFB,VINV
A
P
d
Limits
5.5
0.69
V
IN
2
EN/SYNC, EN pin voltage
V
IN
VSW
ISW
50
W
Topr
Tstg
Tjmax
-
40 ~ +95
-
40 ~ +125
-
55 ~ +150
˚C
˚C
˚C
Power supply
voltage
Operating temperature
range
V
IN
36
V
V
V
*1
4
*1
*2
*3
RT, FB, INV pin voltage
Storage temperature range
Maximum junction temperature
7
150
BD9778F/HFP
7 ~ 35
~ 2
6 ~ 100
50 ~ 500
40 ~ 800
Parameter
Operating power supply voltage
Output switch current
Output voltage (ON Duty)
Oscillation frequency
Oscillation frequency set resistance
BD9001F
7 ~ 48
~ 2
6 ~ 100
50 ~ 300
100 ~ 800
BD9781HFP
7 ~ 35
~ 4
6 ~ 100
50 ~ 500
39 ~ 800
Unit
V
A
%
kHz
kΩ
Possible operating range
BD9778F/HFP
5 ~ 35
Parameter
Operating power supply voltage
BD9001F
7 ~ 48
BD9781HFP
5 ~ 35
Unit
V
BD9778F/HFP (Unless otherwise specified, Ta = -40˚C to +125˚C, VIN =13.2 V, VEN = 5 V)
Circuit current
Standby circuit current
Reference voltage 2
Reference voltage 1
[Error Amp block]
Reference voltage input regulation
Input bias current
Maximum FB voltage
Parameter
Limits
Typ.Min. Max.
0.96
-
-
-
Operating output current of overcurrent protection
2
-
Symbol
I
OLIMIT
IOLEAK
VREF2
VREF1
∆VREF
IQ
ISTB
RON
IB
VFBH
VFBL
IFBSINK
IFBSOURCE
TSS
FOSC
VEN
IEN
∆FOSC
-
1
2.4
70
-
-
82
-
0.8
-
Condition
V
EN=5V
V
FB=VINV
VFB=1.5V,VINV=1.5V
VFB=1.5V,VINV=0.5V
kHz
V
IN=5 ~ 35V
V
IN=5 ~ 35V
V
INV=1.1V
VINV=0.5V
V
INV=1.5V
V
IN=35V,VEN=0V
V
EN=0V,Ta=25˚C
I
O=0A
I
SW=50mA
* Design assurance
* Design assurance
Output leak current
[SW block]
POWER MOS FET ON resistance
Minimum FB voltage
FB sink current
FB source current
Soft start time
[Oscillator block]
Oscillation frequency
Frequency input regulation
[Enable block]
Threshold voltage
Sink current
-
-
5.0
Unit
A
µA
µA
V
%
mA
Ω
µA
V
V
mA
µA
mS
R
T=390kΩ
V
µA
%
1.00
3
0.53
4
0.5
-
2.5
120
0.05
5
102
1
1.7
13
0
0
-
3.0
1.04
0.98 V
FB=VINV,Ta=25˚CV1.00 1.02
4.2
10
0.9
-
-
-
-
170
0.10
-
122
-
2.6
50
30
-
0.5
* Not designed to be radiation-resistant.
www.rohm.com
© 2010 ROHM Co., Ltd. All rights reserved.
BD9778F, BD9778HFP, BD9001F, BD9781HFP
Dec.2015 - Rev.C