AP4809 Datasheet, PDF (6/9 Pages) Anachip Corp – Stereo Headphone Amplifier With Shutdown Mode

Stereo Headphone Amplifier With Shutdown Mode
AP4809
„ Application Information (Continued)
4.1 Output Pull-Down Resistor, R_C + R_O
Placing a 100Ω resistor, R_C, from the output side of
the coupling capacitor to ground insures the coupling
capacitor, C_C, is charged before a plug is inserted
into the jack. Without this resistor, the coupling
capacitor would charge rapidly upon insertion of a
plug, leading to an audible pop in the headphones.
Placing a 20kΩ resistor, R_O, from the output of the IC
to ground insures that the coupling capacitor fully
discharges at power down. If the supply is rapidly
cycled without this capacitor, a small pop may be
audible in 10kΩ loads.
4.2 Using Low-ESR Capacitors
Low-ESR capacitors are recommended throughout
this application. A real capacitor can be modeled
simply as a resistor in series with an ideal capacitor.
The voltage drop across this resistor minimizes the
beneficial effects of the capacitor in the circuit. The
lower the equivalent value of this resistance, the
more the real capacitor behaves like an ideal
capacitor.
„ Marking Information
( Top View )
8
5
Logo
AP4809
Part number
YY WW X
1
4
ID code: internal
Xth week: 01~52
Year: "01" = 2001
"02" = 2002
SOP-8L/PDIP-8L
Logo
Part number
(Top View)
YM X
4809
MSOP-8L
ID code: internal
Date code:
Y: Year : 0~9
M: Month (A~L)
Anachip Corp
www.anachip.com.tw
Rev. 1.0 Sep 29, 2004
6/9