ETC BA20372

2W Stereo Class-D Audio
Power Amplifier
BA20372
Brief Data Sheet
Preliminary Version
Rev.1.1, 2006.01.26
Biforst Technology Inc.
BA20372
____
2W Stereo Class-D Audio Power Amplifier
2W Stereo Class-D Audio Power Amplifier
BA20372
GENERAL DESCRIPTION
The BA20372 is a 5V class-D amplifier from Biforst Technology. BA20372 provides dc volume
control, lower supply current, high efficiency & few external components for driving speaker directly.
BA20372 also integrates Anti-Pop, Output Short & Over-Heat Protection Circuitry to increase device
reliability. The functionality makes this device ideal for LCD projectors, LCD monitors, powered
speakers & other applications that demand more battery life.
FEATURE
2W Per Channel Into 3-Ω Speakers (THD+N = [email protected])
Operation Voltage From 3.3 To 5.5V
DC Volume Control From –38dB to 20dB
Low Shutdown Control : <10μA
Low Noise Floor, -80dBV
Maximum Efficiency into 3-Ω, 77%
Maximum Efficiency into 8-Ω, 87%
Preliminary Version
PSRR, -71dB
Integrated Anti-Pop Circuitry
Integrated Output Short Protection Circuitry
Integrated Over-Heat Protection Circuitry
Provide DC Volume Control
2.80
2.60
2.40
2.20
2.00
1.80
1.60
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
THD 1%-3Ohm
THD 10%-3Ohm
THD 1%-4Ohm
THD 10%-4Ohm
THD 1%-8Ohm
THD 10%-8Ohm
3.3
3.4
3.5
3.6
3.7
3.8
3.9
4.0
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
5.0
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
6.0
Output Power Per Channel (W)
Operate Voltage vs Output Power
Operate Voltage (V)
_________________________________________________________________________________________________
Biforst Technology, Inc., reserves the right to change product or specifications without notice.
Page 2 of 5
BA20372
____
2W Stereo Class-D Audio Power Amplifier
Chip List:
Chip Name
2W Stereo Class-D Audio Power Amplifier
IC No.
BA20372
Chip Package
QFN 32pins
LINN
OSC_R
VOLUME
OSC_C
SHUTDOWN_B
C_BYPASS
RINN
RINP
24
23
22
21
20
19
18
17
PIN ASSIGNMENTS
LINP
25
16
VDD
VDD
26
15
VSS
VSS
27
14
VSS
13
VSS
12
PVSS_A
BA20372
5x5x0.8mm
VSS
28
PVSS_A
29
PVSS_A
30
11
PVSS_A
PVSS_A
31
10
PVSS_A
PVSS_A
32
9
PVSS_A
1
2
3
4
5
6
7
8
LOUTN
LOUTP
PVDD_A
PVDD_A
PVDD_A
PVDD_A
ROUTP
ROUTN
(Top View)
Preliminary Version
PIN LIST & DESCRIPTION
Pin No.
Pin
I/O Pad Function
Type
1
LOUTN
Output
Left channel negative output
2
LOUTP
Output
Left channel positive output
3
PVDD_A
4
PVDD_A
5
PVDD_A
Power
5V power supply
6
PVDD_A
7
ROUTP
Output
Right channel positive output
8
ROUTN
Output
Right channel negative output
9
PVSS_A
Power
5V ground
Power
5V ground
10
PVSS_A
11
PVSS_A
12
PVSS_A
13
VSS
14
VSS
15
VSS
16
VDD
Power
5V power supply
17
RINP
Input
Right channel positive differential audio input
18
RINN
Input
Right channel negative differential audio input
19
C_BYPASS
Input
Connect a 1-uF capacitor from C_BYPASS to ground for internal bias
reference
_________________________________________________________________________________________________
Biforst Technology, Inc., reserves the right to change product or specifications without notice.
Page 3 of 5
BA20372
Pin No.
Pin
____
2W Stereo Class-D Audio Power Amplifier
I/O Pad Function
Type
Shut down control for BA20372, Logic low is placed on this terminal for
20
SHUTDOWN_B
Input
shut down mode, Logic high is placed on this terminal for normal
operation
A capacitor connected to this terminal sets the oscillation in conjunction
21
OSC_C
Input
with OSC_C. For proper operation, connect a 220-pF capacitor from
OSC_C to ground
DC volume control for setting the gain on the internal amplifier. The dc
22
VOLUME
Input
23
OSC_R
Input
24
LINN
Input
Left channel negative differential audio input
25
LINP
Input
Left channel positive differential audio input
26
VDD
Power
5V power supply
27
VSS
28
VSS
Power
5V ground
29
PVSS_A
30
PVSS_A
31
PVSS_A
Power
5V ground
32
PVSS_A
voltage range is 0 to VDD
A resistor connected to this terminal sets the oscillation in conjunction
with OSC_R. For proper operation, connect a 120-kΩ resistor from
OSC_R to ground
PACKAGE DIMENSION
QFN 32
Preliminary Version
_________________________________________________________________________________________________
Biforst Technology, Inc., reserves the right to change product or specifications without notice.
Page 4 of 5
BA20372
Symbol
____
2W Stereo Class-D Audio Power Amplifier
Dimension (mm)
Min.
Nor.
Max.
A
0.70
0.75
0.80
A1
0
0.02
0.05
C
0.20 REF
b
0.18
D
0.25
0.30
5.00 BSC
D2
1.25
E
2.70
3.25
5.00 BSC
E2
1.25
e
2.7
3.25
0.50 BSC
L
0.30
y
0.40
0.50
0.10
CONTACT INFORMATION
Biforst Technology Inc.
8F-3, No.26, Tai Yuen St., Jubei City, Hsin-Chu, Taiwan, R.O.C.
Tel: 886-3-552-6521; Fax: 886-3-552-6558; Email: [email protected]
Preliminary Version
Version History
Version
Date
1.0
2005.12.14
1.1
2006.01.26
Page
Description
First Release
2
Add features of DC Volume Control, Low
Shutdown Control, Low Noise Floor, Max.
Efficiency & PSRR.
Update Graph “Output Voltage vs. Output
Power”
_________________________________________________________________________________________________
Biforst Technology, Inc., reserves the right to change product or specifications without notice.
Page 5 of 5