ROHM BA3571

BA3571F
Audio ICs
Headphone driver for
portable CD players
BA3571F
The BA3571F is headphone drivers designed for portable CD players. An oscillation damper is not needed at the
headphone output, minimizing external components. Includes a bass boost circuit which enables setting of the bass
boost with external components.
!Applications
Portable CD players
!Features
1) An external oscillation damper is not needed.
2) Includes a bass boost circuit making it possible to set
the bass boost with attached components.
!Absolute maximum ratings (Ta = 25°C)
Parameter
Symbol
Limits
Power supply voltage
VCC
5.5
Power dissipation
Pd
550 *1
Unit
V
mW
Operating temperature
Topr
-25~+75
˚C
Storage temperature
Tstg
-55~+125
˚C
*1 Reduced by 5.5mW for each increase in Ta of 1˚C over 25˚C.
!Recommended operating conditions (Ta = 25°C)
Parameter
Symbol
Min.
Typ.
Max.
Unit
Power supply voltage
VCC
2.0
-
5.5
V
BA3571F
Audio ICs
10
9
8
7
19
Bias out
6
18
Bias in
5
17
IN 1
BB SW
LP Out
4
16
NC
BB SW τ
LP NF
3
15
Ripple Filter
τ
IN 2
2
14
NC
Out 2
LP IN
1
13
NC
Power GND
Pre GND
Pre
GND
VCC
39k
50k
RF1
BB SW
12
Vcc 2
GND
11
Out 1
VCC
Vcc 1
20
!Block diagram
BA3571F
Audio ICs
!Electrical characteristics
_ (unless otherwise noted, Ta = 25°C, VCC = 3V, RL = 16Ω, and f = 1kHz; measurement circuit shown in Fig.1)
Parameter
Symbol
Min.
Typ.
Max.
Unit
IQ
-
9
18
mA
VIN = 0Vrms
Voltage gain 1
GV1
13.5
15
16.5
dB
BB = OFF
Voltage gain 2
GV2
11.5
13
14.5
dB
BB = ON
Rated output power
POUT
20
30
-
mW
THD = 10%
Total harmonic distortion
THD
-
0.15
1.0
%
VO = -16dBm
CB
-1.5
0
1.5
dB
VO = -16dBm
Output noise voltage 1
VNO1
-
-92
-88
dBm
BB = OFF, IHF - A
Output noise voltage 2
VNO2
-
-88
-84
dBm
BB = ON, IHF - A
Input resistance
RIN
10.8
13.5
16.2
kΩ
Ripple rejection
RR
23
36
-
dB
f RR = 100Hz, VRR = -30dBm, BB = OFF
Quiescent current
Channel balance
Conditions
Boost
BB
4
6
8
dB
f = 100Hz, VIN = -36dBm
Channel separation
CS
52
62
-
dB
f = 1kHz, BB = OFF
* Not designed for radiation resistance.
!Measurement circuit
10k
1µ
+
~
VCC
1
1
A
SW5
2
1
47
SW3
13k
33µ
20
19
220µ
+
1 2
+
17
18
33µ
16
16
2
SW1
SW2
2
+
15
14
13
12
11
RF1
V
~
THD
VCC
VCC
+
220µ
50k
39k
Pre
GND
GND
BB SW
3
2
1
4
1 2
100k
13k
100k
SW3
5
6
+
SW4
2.2µ
5.1k 0.1µ
1 2
THD
8
7
10
9
+
0.22µ
+
220µ
V
~
16
1
2
~
GND
0.1µ
~
Units
Resistors
: Ω (±1%)
Capacitors
: F (±1%)
Capacitors (electrolytic) : F (±5%)
+
1
1µ
10k
2
SW6
Fig. 1
BA3571F
Audio ICs
!Application example
+
LINE OUT
1µ
10k
4.7k
VCC
+
33µ
220µ
33µ
+
20
19
16
17
18
+
15
12
13
14
11
RF1
VCC
VCC
50k
39k
Pre
GND
GND
BB SW
3
2
1
1µ 4.7k
+
5
+
2.2µ
5.1k
0.1µ
LINE OUT
4
100k
100k
+
10
9
8
7
6
0.1µ
0.22µ
+
220µ
GND
Units
Resistors
: Ω (±5%)
Capacitors
: F (±10%)
Capacitors (electrolytic) : F (±20%)
10k
Fig. 2
!Electrical characteristic curve
!External dimensions (Units: mm)
20
BB OFF
BB ON
12.5±0.2
100
1k
10k
FREQUENCY : f (Hz)
11
1
10
1.27
0.4±0.1
Fig. 3 Voltage gain vs. frequency
0.15±0.1
-10
20
5.4±0.2
0
1.8±0.1
7.8±0.3
10
0.11
VOLTAGE GAIN : GV
(dB)
BA3571F
30
0.3Min.
0.15
SOP20