Yamaha DSP-AX620 Service Manual page 37

IC587 : LC74781-9798 (OPERATION P.C.B.)
Superimpose
Pin No. Symbol Terminal name
Ground terminal
1 VSS1
Crystal oscillation
2 XTAL IN
terminal
3 XTAL OUT
Crystal oscillation input
4 CTRL1
switching terminal
Blank output terminal
5 BLANK
LC oscillation terminal
6 OSC IN
7 OSC OUT
Character output terminal
8 CHARA
Enable input terminal
9 /CS
Clock input terminal
10 SCLK
Data input terminal
11 SIN
Power supply terminal
12 VDD2
Video signal output terminal
13 CV OUT
14 NC
Video signal input terminal
15 CV IN
Power supply terminal
16 VDD1
Synchronous separation
17 SYN IN
circuit input terminal
Synchronous separation
18 SEP C
circuit bias voltage terminal
Complex synchronous
19 SEP OUT
signal output terminal
Vertical synchronous
20 SEP IN
signal input terminal
NTSC/PAL-M switching
21 CTRL2
input terminal
SEPIN input control terminal
22 CTRL3
Reset input terminal
23 /RST
Power supply terminal (+5V)
24 VDD1
Connection to GND (Digital system ground terminal)
Terminal to connect the crystal of the crystal oscillator for internal synchronous
signal generation and a capacitor or to input an external clock. (2fsc or 4fsc)
Switching terminal between the mode to input a clock externally and the mode
for crystal oscillation. [L] = Crystal oscillation, [H] = External clock input
Terminal to output the blank signal (character and bordering OR signal) (MOD0 :
complex synchronous signal output at [H]). When resetting (RST terminal = [L]),
a crystal oscillation clock is output (but not when resetting by the command).
Terminal to connect the coil of the oscillator for character output dot clock
generation and a capacitor.
Terminal to output a character signal (MOD0 : It becomes an output terminal to
judge the external synchronous signal at [H] and outputs the result after judging
existence of the external synchronous signal. When a synchronous signal exists,
[H] is output.) When resetting (RST terminal = [L]), a dot clock (LC oscillation) is
output (but it is not output when reset by the command.)
Serial data input enable input terminal. The serial data input becomes enable at
[L]. A pull-up resistor is built in (hysteresis input).
Input terminal of clock for serial data input.
A pull-up resistor is built in (hysteresis input).
Serial data input terminal. A pull-up resistor is built in (hysteresis input).
Power supply terminal for complex image signal level adjustment (Power supply
for analog system)
Output terminal for complex image signal.
Connected to GND or unconnected.
Input terminal for complex image signal.
Power supply terminal (+5V : power supply for digital system)
Video signal input terminal of the built-in synchronous separation circuit (When
the built-in synchronous separation circuit is not used, it becomes a horizontal
synchronous signal input or a complex synchronous signal input.)
Terminal to monitor built-in synchronous separation circuit bias voltage.
Terminal to output a complex synchronous signal of built-in synchronous
separation circuit ([H] when internally synchronized at MOD1 : [H], [L] output
when externally synchronized) (When the built-in synchronous separation circuit
is not used, SYNIN input signal is output.)
Terminal to input a vertical synchronous signal by integrating the output signal of
SEPOUT terminal. Connect the integration circuit between SEPOUT terminals.
Fix it to VDD1 when not used.
Pin setting has a priority over switching of NTSC/PAL/PAL-M/PAL-N method.
The NTSC method is selected after [L]= reset.
NTSC/PAL/PAL-M/PAL-N method setting by a command is effective.
[H] = PAL-M method.
Terminal to control whether or not to input VSYNC signal into SEPIN input
terminal. [L] = VSYNC inputted, [H] = VSYNC not inputted.
System reset input terminal. A pull-up resistor is built in (hysteresis input).
Power supply terminal (+5V : power supply for digital system)
DSP-AX620
Function
36