SM8220/SM8221
TIMING DIAGRAM
1st Ring
INPUT
(TIP, RING)
101010... 1
Data
2nd Ring
RDRC*
V
IH2
V
IL2
RDET*
PDWN
t
SUPD
CDET
t
DAQ
DOUT
101010... 1
Data
t
DCH
OSCOUT*
t
DOSC
*: Not available for SM8221.
TYPICAL APPLICATION CIRCUIT
SM8220
0.001µF
91kΩ (240kΩ)
+5V
( ) = When 3V range
Protection
Network
TIP
RING
AGND
RDIN
VDD
FOUT
DMIN
DOUT
Controller
NC
CDET
OSCOUT
OSCIN
/CLKIN
3.579545
MHz
0.1µF
10µF
0.001µF
91kΩ (240kΩ)
0.1µF
From TIP
From RING
0.2µF
0.2µF
270kΩ
470kΩ
RDRC
RDET
33kΩ
0.2µF
PDWN
GND
LCD Driver
LCD Display
+5V
SM8221
0.001µF
91kΩ (240kΩ)
( ) = When 3V range
Protection
Network
0.001µF 91kΩ (240kΩ)
TIP
RING
PDWN
VDD
DOUT
10µF
Controller
CDET
CLKIN
3.579545MHz
From TIP
GND
From RING
LCD Driver
LCD Display
(Note)
When the Ring Detect feature of SM8220 is not used, always connect RDIN and RDRC pins to the system ground level.
This will cut excess current drain from VDD under the normal and power down mode of operation.
This diagram example is desingned to adapt to the specifications of United States.
When it is used in other area, the constants may have to chenged appropriately.
NIPPON PRECISION CIRCUITS-7
NPC [ NIPPON PRECISION CIRCUITS INC ]
