bd5465gul ROHM Co. Ltd., bd5465gul Datasheet - Page 7

• Manufacturer Part Number: bd5465gul
• Description: Analog Input Monaural Class-d Speaker Amplifier
• Manufacturer: ROHM Co. Ltd.

●About the difference of differential input and single end input
© 2010 ROHM Co., Ltd. All rights reserved.
BD5465GUL
www.rohm.com
・BD5465GUL uses full differential amplifier.
About the resistor, signal
Gives meaning to changes of gain setting by means of ALC Control.
○About single end input
・Input is possible whether IN+ or IN- Pin.
・During single end input IN+ and IN-, there is a difference with the phase relation of input and output.
BD5465GUL is a Class-D amplifier, but, in relation to Audio Input and Output, is same with the conventional Class-AB
amplifier. For simplicity purposes of the diagram, the Class-D amplifier output stage is omitted in the following
explanation.
Don’t make input pin open, through the input coupling capacitor, please connect to GND as seen on the example above.
Audio input pin should make “mute” condition, not “open” condition when you don’t input any signal.
Because of differential amplifier, if input (IN+ - IN-), output(OUT+ - OUT-), the audio input and output phase relation
will become:
Audio Input ⇒ output (OUT+ - OUT-)
1) Differential Input
2) Single end input (during IN+input )
3) Single end input (during IN-input )
Audio
Audio
Input
Audio
Audio
Input
Input
Input
Phase
0V
0V
0V
0V
0V
0V
on the diagram
ー
ー
IN+
IN+
IN+
IN-
IN-
IN-
A1
C1
A1
C1
A1
C1
ー
ー
(IN+ - IN- )
(IN+ - IN- )
(IN+ - IN- )
Same phase
IN+ Input
7/19
Opposite
Opposite
Opposite
Opposite
phase
phase
phase
phase
Opposite phase
(OUT+ - OUT- )
(OUT+ - OUT- )
(OUT+ - OUT- )
OUT-
OUT-
OUT+
IN- Input
OUT+
OUT-
OUT+
A3
C3
A3
C3
A3
C3
Technical Note
2010.09 - Rev.A