Hi,
Am using 14 pin version of LM2907 IC. Input frequency is RPM feedback from a tachometer. Maximum input freq expected is 13 kHz.
Circuit works fine over full range of frequency with square wave input with 50% duty cycle.
Practically, tachometer feedback thru optical pulse pick up then converted to electrical signal fed as input signal to LM2907 which has >80% duty cycle.
Ref Voltage at 11 Pin :1.2 V
Input freq signal amplitude 0 - 3.3V.
Supply Voltage :24V
C1 :470pF, R1: 10kOhms.
With 80% or more duty cycle, output voltage saturates around 3kHz frq.
Please help me out to solve this.
Thanks & Regards,
Chandan N
