TEA6821T Philips Semiconductors, TEA6821T Datasheet - Page 30

• Manufacturer Part Number: TEA6821T
• Description: ICE car radio
• Manufacturer: Philips Semiconductors

Philips Semiconductors
Output signal of reference frequency divider
IF-counter; note 1
Note
1. Counting windows AM: 4 ms, (40 ms); FM: 40 ms, 4 ms
The IF-count windows are valid for a crystal oscillator frequency of 61.5 MHz.
The FM/AM switching is done by bit 0 of byte 2 of the received data of the IC.
The IF-counter operates continuously.
The IF-counter and window-counter will be resetted when the I
changes in the latches for the IF-count, while reading this value. If the transmission to the front end IC will be disabled
after the synthesizer loop of the TEA6811T front end IC has locked for a new frequency, the IF-count will be available
after the set measuring time.
The IF-counter starts at 0. The IF-counter output are the 8 least significant bits of the counting result.
September 1993
C
R
V
V
V
V
10-11
10-4,
33-34
37-35
ICE car radio
10-4,
10-52,
Counting resolution AM: 250 Hz, (25 Hz); FM: 5 kHz, 50 kHz
IF-prescaler AM: division by 1; FM: division by 200
SYMBOL
SYMBOL
V
C
R
11-4
11-4
11-52
output capacitance
output resistance
differential output voltage (peak-to-peak value)
single-ended output voltage (peak-to-peak value)
IF-counter sensitivity for AM, m = 0
IF-counter sensitivity for FM
PARAMETER
Fig.23 IF-counter structure.
PARAMETER
30
2
C-bus logic detects the address of the IC. This disables
800
0.3
0.15
MIN.
1000
0.4
0.2
TYP.
Preliminary specification
4
1200
0.5
0.3
200
200
TEA6821T
MAX.
MIN.
pF
V
V
UNIT
V
V
UNIT