Rainbow Electronics aP8910A - Manual (Page 16)

Integrated Circuits Inc. aP8921A/10A
Ver 2.0 Dec 6, 2006 16
TYPICAL APPLICATIONS
Fig. 12 Using 4.5V Battery
Note 1: Two capacitors Cin and Cout must be connected from VDD and V33 pins to VSS to
stabilize the power supply to the chip. When small capacity battery, e.g. AG10, is
used, Cin and Cout may need to be as large as 22uF. However, if Cin and Cout is
too large, the power-up reset generated by 0.1uF at the RST pin may not be function
because it takes longer time for both Cin and Cout to discharge.
Note 2: 16 Ohm speaker will provide lauder and better sound quality when the VOUT speaker
direct drive is used.
Note 3: The value of the 390 Ohm base resistor should be modified according to different Vdd
value, the kind of speaker and NPN transistor.
Note 4: The VPP pin should be leave unconnected for playback.
RST
OSC
S1
S2
S3
S4
SBT
VSS
VDD V33
COUT
OUT1
VOUT2
VOUT1
4.5~5V
0.1uF
4.7uF
0.1uF
1KΩ
390Ω
8050D
Ros c
16 Ω
Speaker
8 ΩSpeaker
Cin
1~2uF
Cout