NIPPON PRECISION CIRCUITS-7

SM8220/SM8221

TIMING DIAGRAM

TYPICAL APPLICATION CIRCUIT

101010... 1

Data

1st Ring

2nd Ring

101010... 1

Data

INPUT

(TIP, RING)

PDWN

DOUT

OSCOUT*

RDRC*

RDET*

CDET

*: Not available for SM8221.

Protection

Network

TIP

RING

AGND

RDIN

RDRC

RDET

PDWN

GND

VDD

DOUT

NC

DMIN

FOUT

CDET

OSCOUT

OSCIN

/CLKIN

SM8220

Controller

From TIP

From RING

0.001

0.2

µF

0.2

µF

0.001

0.1

µF

470k

Ω

33k

Ω

270k

Ω

0.2

µF

10

µF

0.1

µF

+5V

LCD Driver

LCD Display

3.579545

MHz

( ) = When 3V range

Protection

Network

TIP

RING

PDWN

GND

VDD

DOUT

CLKIN

SM8221

Controller

From TIP

From RING

0.001

µF 91kΩ (240kΩ)

0.001

µF 91kΩ (240kΩ)

10

µF

+5V

LCD Driver

LCD Display

CDET

3.579545MHz

( ) = When 3V range

(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.