bd5465gul ROHM Co. Ltd., bd5465gul Datasheet - Page 10

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

© 2010 ROHM Co., Ltd. All rights reserved.
BD5465GUL
www.rohm.com
2)
■Caution during External LPF Setting
External LPF Resistor R
The bigger the resistor value of LPF resistor R
When the input capacitor Ci has enough large capacity value, the relation among external LPF resistor R
IC input resistor Ri and Gain will become:
Input resistor Ri of BD5465GUL and resistor value of feedback resistor Rf will become the following below,
during ALC operation, changes at ±1dB step, and becomes 16 stages switch specs.
Also with the driver ability of previous IC step, after checking, constant setting of external LPF and Resistor R
Differential Input
Front IC
Gain = 20×log | Rf / (Ri + R
#1. Ri=60kΩ(Typ.), Rf=240kΩ(Typ.)@Gain=12dB
#2. Ri=66kΩ(Typ.), Rf=234kΩ(Typ.)@Gain=11dB
#3. Ri=72kΩ(Typ.), Rf=228kΩ(Typ.)@Gain=10dB
#15. Ri=167kΩ(Typ.), Rf=133kΩ(Typ.)@Gain=-2dB
#16. Ri=176kΩ(Typ.), Rf=124kΩ(Typ.)@Gain=-3dB
Ro
Ro
Shutdown Signal
H : IC Active
L: IC Shutdown
R
R
LPF
LPF
Input Impedance
LPF
LPF
which is composed of IC input resistor Ri, forms input impedance.
C
C
LPF
LPF
↓
Ci
Ci
SDNB
LPF
IN+
IN -
C 2
A1
C 1
) |
Ri
Ri
[dB]
LPF,
(Typ.)
150k
the more it will decrease the gain.
Shutdown
Control
10/19
Rf
Rf
ALC
VDD
GND
+ Battery
B1
A2 B3
B2 PVDD
PWM
BIAS
OSC
PGND
Bridge
Cs
H-
C 3
A 3
OUT +
OUT -
Technical Note
2010.09 - Rev.A
LPF
Speaker
and
LPF.