ta1372fng TOSHIBA Semiconductor CORPORATION, ta1372fng Datasheet - Page 6

• Manufacturer Part Number: ta1372fng
• Description: Vhf Band Rf Modulator Ic For Vcrs And Set Top Boxes
• Manufacturer: TOSHIBA Semiconductor CORPORATION

Explanation in each mode
1. Reference signal Mode selection (Pin 1)
2. Test mode selection (Pin 5)
3. Carrier off mode selection (Pin 6)
4. Channel selection (Pin 8)
5. P/S ratio set up (Pin 16)
As reference signal, either 4-MHz crystal resonator can be connected to this pin for internal oscillation or
external signal can be input. Reference signal Mode can be selected pin 1. 4MHz and 3.579545MHz can be
used for the frequency of an external input signal.
Pin 5 is also used for switching test mode. Normally this pin is used at 0 V DC (used by AC coupling).
White clip mode is prepared into test mode. ( e.g. when modulation characteristics for near-100%
modulation are being checked.)
If the voltage of a terminal 5 becomes more than 1.2V, it will change to the test mode.
Be careful of the influence of a noise etc.
Pin 6 is selection of Carrier off-mode and Antenna SW driver output. In Carrier off mode, Supply current is
saved by stopping Sound VCO.
When changing a carrier ON, RF output is muted the time of about 130 msec. Mute of RF output is for
avoiding the influence of the noise by RF carrier frequency being unstable. At the time of Channel
switching, RF output is muted similarly.
Pin 8 is the selection of RF VCO oscillation frequency.
P / S ratio is set up by connecting resistance with pin 16 between GND. P / S ratio can be set as the range of
–9dB to -17dB.
Voltage of pin 6
Low or Open
High
Voltage of pin 1
High or Open
Middle
Voltage of pin 5
Low
Low or Open
Voltage of pin 8
High or Open
Middle
High
RF&sound oscillation
Low
OFF
ON
Internal oscillation with 4MHz X tal
6
3.579545MHz External input
White Clip through mode
Reference signal mode
USA 3ch (61.25MHz)
USA 4ch (67.25MHz)
4MHz External input
Normal mode
(Test mode)
Test mode
Channel
Mode
Antenna SW driver output (pin 14)
High
Low
TA1372FNG
2003-12-25