SM8578BV
Monitoring Oscillator Frequency
A 1Hz signal is output from INTN when input CE is biased to 1/2VDD.
By monitoring this output, the oscillator frequency can be adjusted by tuning an external capacitor (CG).
XTN
XT
CG
VDD
R1
C1
SW
CE
R2
VSS
R3
INTN
INTN output (1Hz)
R1 = R2 ( ≈ 10kΩ)
R3 ≈ 10kΩ
C1 ≈ 0.1µF
TYPICAL APPLICATION CIRCUIT
SM8578BV
VDD
INTN
XT
XTN
VSS
CE
CLK
DATA
VCC
VCC
Micro
controller
GND
NIPPON PRECISION CIRCUITS INC.—15