BA9700A / BA9700AF / BA9700AFV
Regulator ICs
Switching regulator for DC / DC
Converters
BA9700A / BA9700AF / BA9700AFV
The BA9700A, BA9700AF and BA9700AFV are switching regulators that use a pulse width modulation (PWM) system.
They use a transistor switch to stabilize the output voltage.
By the use of the transistor, power loss is decreased, fluctuation efficiency is improved, and the circuit is made more
compact and single.
!
Features
1) Output voltage can step up, step down, or invert at an
arbitrary level.
2) Low current consumption. (typically 1.7mA)
3) Wide oscillation frequency range.
(typically 2.8k ~ 470kHz)
4) Built-in reference voltage current. (typically 2.57V)
5) Operates at low voltage. (minimally 3.55V)
!
Block diagram
NON
INVERT
INPUT
14
1/2 V
ref
13
INVERT
INPUT
12
V
ref
11
6) Dead time controller restricts operation when
overloaded.
7) Power switch can isolate all circuits in the IC.
8) Best suited for battery operated equipment.
9) Compact 14-pin SSOP package (BA9700AFV).
POWER
SW
10
N. C.
9
V
CC
8
+
−
Error
Amp
30k
30k
V
ref
Voltage
Regulator
BA9700A
BA9700AF
PWM
Comparator
Triangle
Oscillator
1
D - TIME
CONT
2
R
T
3
C
T
4
FEED
BACK
5
OUT
6
N. C.
7
GND
!
Absolute maximum ratings
(Ta = 25°C)
Parameter
Power supply voltage
Symbol
V
CC
Limits
24
600
*
1
350
*
2
350
*
3
Unit
V
BA9700A
Power
dissipation
BA9700AF
BA9700AFV
Pd
mW
Operating temperature
Storage temperature
Topr
Tstg
-20~+80
-55~+150
°C
°C
*
1 BA9700A: Reduced by 4.8 mW for each increase in Ta of
1˚C over 25˚C.
*
2 BA9700AF: Reduced by 4.4 mW for each increase in Ta of
1˚C over 25˚C.
*
3 BA9700AFV : Reduced by 3.5 mW for each increase in Ta of
1˚C over 25˚C.
*
2,
*
3 When mounted on a 5.0´5.0´1.6 mm glass epoxy board.
BA9700A / BA9700AF / BA9700AFV
Regulator ICs
!Electrical
characteristics
(unless otherwise noted, Ta = 25°C, V
CC
= 5.0V, R
t
= 10kΩ, and C
t
= 330pF)
Parameter
〈Reference
voltage section〉
Output voltage
1/2 V
ref
output voltage
Line regulation
Load regulation 1
Load regulation 2
Output voltage when power decreases
Output current when short-circuited
〈Triangular
wave oscillation section〉
Oscillation frequency
Standard deviation of
oscillation frequency
Frequency variation (V
CC
)
〈Error
amplifier section〉
Input offset voltage
Input offset current
Maximum input voltage
Open loop gain
Common-mode rejection ratio
Input bias current
〈PWM
comparator section〉
Threshold voltage 1
Threshold voltage 2
〈Output
section〉
Output transistor leakage current
Output saturation voltage
〈Total
device〉
Quiescent current
Standby current
Operating voltage
Symbol
Min.
Typ.
Max.
Unit
Conditions
V
ref
1/2 V
ref
Line
Load1
Load2
V
ref
Iosc
2.48
1.22
-
-
-
2.48
-
2.57
1.29
3.00
1.00
6.00
2.57
10.0
2.66
1.36
12.0
5.00
10.0
2.66
30.0
V
V
mV
mV
mV
V
mA
I
ref
= 0.1mA
V
CC
= 3.55V~24V
I
ref
= 0.1mA~1.0mA
I
ref
= 0.1mA~8.0mA
I
ref
= 0.1mA, V
CC
= 3.55V
V
ref
= 0V
fosc
fosc
fdv
-
-
-
230
10
1
-
-
-
kHz
%
%
R
T
= 10kΩ, C
T
= 330pF
R
T
and C
T
are constant
V
CC
= 3.55~24V
V
IO
I
IO
V
ICR
A
V
CMRR
I
IB
-6.0
-100
1.60
70.0
70.0
-
-
-
1.90
80.0
80.0
180
6.0
100
-
-
-
500
mV
nA
V
dB
dB
nA
Null Method
Null Method
Null Method
Null Method
Null Method
Null Method
V
t0
V
t100
-
1.25
2.04
1.43
2.24
-
V
V
µA
V
DUTY 0%
DUTY 100%
Leak
Vsat
-
-
-
1.70
10.0
2.10
V
O
= 24V
I
O
= 50mA
I
CC
I
CCS
V
CC
-
-
3.55
1.70
0
-
2.40
7.00
24.0
mA
µA
V
R
T
= OPEN POWER SW = 2.5V
POWER SW = 0V
BA9700A / BA9700AF / BA9700AFV
Regulator ICs
Q
1
2SB1009
R
9
GND
8
47k
10
3
2
SW
1
C
7
1000p
R
8
10k
RB100A
V
OUT
D
1
V
IN
C
6
470µ
330
R
7
L
1
220µH
C
4,
C
5
470µ
×2
11
2.57V
30k
Voltage
Regulator
V
ref
Triangle
Oscillator
GND
13
1.29V
30k
ERROR AMP
9
330
R
6
R
1
33k
14
R
3
6.8k
6
+
−
R
2
7.5k
0.047µ
C
2
C
1
12
680p
4
PWM COMPARATOR
5
7
C
3
1µ
1
L1: RCH-875 220K (Sumida Electronics)
R
4
22k
R
5
39k
Fig.3 Inverting converter
L
1
V
IN
R
11
GND
8
47k
10
3
2
Q
1
2.57V
30k
13
R
1
39k
14
R
2
4.7k
12
C
2
0.047µ
C
1
680p
4
30k
ERROR AMP
+
−
R
3
7.5k
PWM COMPARATOR
5
6
R
6
470
V
ref
1.29V
9
R
7
470
Voltage
Regulator
Triangle
Oscillator
2SB1009
R
8
68
SW
1
C
8
1000p
R
10
10k
C
7
100µ
R
9
470
22µH
RB100A
D
1
12V
V
OUT
C
5,
C
6
470µ
×2
11
Q
2
2SD1380
GND
7
C
4
1µ
1
L1: RCH-875 221K (Sumida Electronics)
R
4
20k
R
5
39k
Fig.4 Step-up converter
BA9700A / BA9700AF / BA9700AFV
Regulator ICs
!
Basic application board patterns and component arrangemrnts
C
3
C
9
R
8
R
5
C
2
C
10
R
3
C
1
BA9700A
( )
+
( )
+
R
1
C
5
L
+
R
4
C
11
C
4
R
2
R
6
V
IN
R
9
V
OUT
Q
1
GND
+
C
8
B
SW
R
7
C
E
GND
+
C
7
C
6
D
BA9700A - 1
Fig.5 Step-down converter
C
2
R
2
C
1
C
7
BA9700A
R
8
R
5
R
4
C
3
C
4
V
OUT
V
IN
SW
R
3
R
9
+
R
1
C
5
R
6
L
Q
1
B
GND
+
C
6
+
GND
D
1
C
E
BA9700A - 2
Fig.6 Inverting converter (BA9700A)
C
3
C
4
C
2
R
10
R
5
R
4
R
3
C
1
BA9700A
R
6
R
2
+
R
1
R
8
Q
1
Q
2
+
B
C
E
C
6
V
OUT
V
IN
SW
R
11
R
7
GND
+
B
C
E
GND
R
9
C
7
L
C
5
Fig.7 Step-up converter (BA9700A)
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