ta1370fg TOSHIBA Semiconductor CORPORATION, ta1370fg Datasheet - Page 40

• Manufacturer Part Number: ta1370fg
• Description: Sync Processor, Frequency Counter Ic For Tv Component Signals
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Application Circuit 2
following figure. One is for frequency measuring (SYNC2-in) and the other is for the AFC (SYNC1-IN). And
measure H/V frequency of signal 2 (fH2: unknown) on condition that AFC is stable (AFC locks in signal 1 (fH1:
known).) or that AFC is free-run when SYNC1-IN is no-signal.
doesn’t lock in the regular frequency, the frequency of pulse (A) will not be correct and the H/V frequency data will
not be showed correct data.
under consideration the factors such as signal strength, existence of ghost signal, H-AFC stability, I
transmission and so on via prototype TV set evaluation.
To measure H/V frequency of signal 2 (fH2: unknown) correctly, use two separated input terminals as the
This IC’s H/V frequency counting is done by internal pulse (A) which is made in AFC circuit. So, if AFC circuit
Decision algorithm of H/V frequency detection (detection range, detection times and so on) should be determined
(fH2: unknown)
(fH1: known)
Signal 1
Signal 2
(How to measure H/V frequency)
H/V freq. counter
SYNC1-IN
SYNC2-IN
for H-AFC
for
40
TA1370FG
Signal 1
AFC
Signal 2
Internal pulse (A)
BUS READ
COUNTER
H/V FREQ
TA1370FG
2
C BUS data
2005-09-05