S1A0903X01-Q0R0 Samsung Electronics, S1A0903X01-Q0R0 Datasheet - Page 31

• Manufacturer Part Number: S1A0903X01-Q0R0
• Description: AM/FM 1 Chip Tuner with PLL
• Manufacturer: Samsung Electronics

AM/FM 1CHIP TUNER WITH PLL
IF COUNTER
Count IF frequency during measurement time(GT[1:0]), start counting on IFCS setting high.
GT1
C[18:0] = F
In Figure. 16
the micro- processor of the end of counting by means of setting DO pin to be low.
0
0
When IFCS bit is zero, IF counter is reset. On IFCS bit is turning to one, IF counter starts to count IF
frequency during measurement time. Then IF counter holds the counted value. If DOC[1:0] is 3, inform
IF counter is automatically reset after sending serial data to Micro- processor and ready to count.
If IF frequency less than 45kHz(FM : 1.07MHz) comes into IF counter during first 100us of measurement
time(GT[1:0]), inform Micro-processor of the end of counting by means of setting DO pin to be low in the
case that DOC[1:0] is 3, even though measurement time isn't passed .
After measurement time(GT[1:0]) is passed, IFCS bit has to be held 1. Unless IFCS bit is held to be one,
counted IF value is all reset to be 0.
IFCS bit is automatically reset after Micro-processor reads the counted IF values.
GT0
IF
0
1
GT : Counted value (the number of pulse)
IF
Measurement
GT[1:0]
Measurement time(GT)
Frequency
Time
4/8/16/
32ms
IF
IFCS
4 ms
8 ms
Figure 15. IF Counter Structure
Figure 16. IF counter operation
GT
GT
GT1
1
1
LSB
0
IF Counter
-
GT0
IFCS
0
1
MSB
18
Measurement time(GT)
DSR
C[18:0]
16 ms
32 ms
S1A0903X01
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