FM1246/HM/I PHILIPS [NXP Semiconductors], FM1246/HM/I Datasheet - Page 14

• Manufacturer Part Number: FM1246/HM/I
• Description: Desktop video & FM radio module system CCIR I
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Components
C
Charge pump settings:
It is recommended to set CP = 1 at all times in the TV mode. In the FM radio mode, set CP = 1 only during the search
tuning. Once the wanted channel is obtained, set CP = 0 to get the best signal-to-noise ratio.
Test mode settings:
PLL disabling:
Ratio select bits
P
Notes
1. If the TV function is not required, the tuner can be switched to power-down mode. In this mode the tuner reduces the
2. By this setting the FM radio AFC status can be read from the A/D bits in the status byte.
3. By this setting the RF input level can be read from the A/D bits in the status byte.
1997 May 14
TV/FM bandswitching
FM band
Low band
Mid band
High band
TV mode
Power down mode; see note 1
System I negative mode
FM radio mode
AFC; see note 2
R
Mono
Mute
ORTS BYTE
ONTROL BYTE
CP = 1, for fast tuning
CP = 0, for moderate speed tuning with slightly better residual oscillator FM.
T2 = T1 = 0; T0 = 1, for normal operation.
OS = 0, for normal operation
OS = 1, for switching the charge pump to the high impedance state. I
IF
Desktop video & FM radio module
system CCIR I
; see note 3
current consumption by up to 100 mA.
RSA
X
0
1
FUNCTION
RSB
0
1
1
50 kHz (for FM band)
31.25 kHz (for slow picture search)
62.5 kHz (for normal picture search)
P7
1
1
1
0
P6
0
0
0
0
14
P5
1
1
0
1
DC
P4
STEP SIZE
0
0
1
1
output voltage is LOW.
BIT
P3
0
0
0
0
0
1
P2
1
0
0
0
0
0
1
1
1
1
Preliminary specification
P1
0
0
0
0
1
0
FM1246
P0
1
0
1
0
0
0