UPD7759C NEC [NEC], UPD7759C Datasheet - Page 3

• Manufacturer Part Number: UPD7759C
• Description: ADPCM SPEECH SYNTHESIZER LSIs
• Manufacturer: NEC [NEC]

1. PIN FUNCTIONS
1.1 COMMON FUNCTION TO ALL MODES
(Abbre-
viation)
V
DRQ
REF
AVO
BUSY
RESET
GND
X1
X2
NC
DD
Pin
14, 20, 26,
27, 33, 39,
40, 46, 52
1, 7, 13,
Pin No.
52-pin
QFP
24
28
29
30
31
32
36
37
6
Pin No.
40-pin
DIP
40
14
16
17
18
19
20
23
24
—
Output
Output
Output
Input
Input
I/O
—
—
—
—
—
Power supply (2.7 to 5.5 V)
Speech synthesis data request.
D/A converter reference current input.
The sink-load current input causes the output current of the
D/A converter to change.
The D/A converter reference current is passed to V
a resistor.
In standby mode, REF is set to high impedance.
Analog speech signal output.
AVO outputs a unipolar sink-load current.
The output current is reduced to 0 when the PD7759 is in the
standby mode.
The output current of the D/A converter from AVO is changed
according to the input current from REF.
Maximum output current of the D/A converter is approx. the
34 times the REF input current.
Active-low BUSY signal output. When inputting ST signal,
it outputs a low level signal.
MD, ST and WR are invalid while BUSY is low.
In standby mode, BUSY is set to high impedance.
Reset input.
In standby mode, RESET must be at low level more than 12
clock cycles after clock oscillation becomes stable.
In operation mode, RESET must be at low level for 12 clock
cycles (oscillation clock).
Ground.
Ceramic resonator connection for generating a clock signal.
The 640 kHz ceramic resonator can be connected.
In standby mode, the PD7759 outputs a low-level to X1 and
a high-level to X2.
No Connection
Function
DD
PD7759
via
3