Denon PMA-720AE Service Manual page 34

ILC7812 Terminal Functions
Pin Functions
Pin
V , V , V
DD SS EE
L1 to L8, R1 to R8,
LCOM1 to LCOM4,
RCOM1 to RCOM4
CL, DI, CE
S
RES
Operation
1. Data Input Procedure
The LC78211, LC78212 and LC78213 are controlled by inputting specified data to the CL, DI and CE pins. The
input data consists of 12 bits, of which four bits are address and eight bits are data.
Bits correspond to the L1 to L8 and R1 to R8 analog switches, and a value of one turns the corresponding switch on,
and a value of zero turns it off.
0.........Off
1.........On
The address is used when the chip is connected to a shared bus. The data (address) that must be transmitted depends
on the S pin and the particular product as shown in the table below.
S pin
Product
level
L
LC78211
H
L
LC78212
H
L
LC78213
H
Note: The bit for switch eight in the LC78213 is a "don't care" bit, that is it can be either 0 or 1 without affecting
chip function. This is because the LC78213 has two sets of seven (not eight) circuits.
LC78211, 78212, 78213
I/O Internal equivalent circuit
See the block diagram.
I
I
I
Address
A A A A
0 1 2 3
0 1 0 1
1 1 0 1
0 0 1 1
1 0 1 1
0 1 1 1
1 1 1 1
Pin function
Power supply
Analog switch input and output
Serial data input (Schmitt buffer)
CL..............Clock input
DI...............Data input
CE .............Chip enable
Selection of one of two chips
The address is set to the values shown in the table below according to
the level input to the S pin.
S pin
Product
level
A
0
L 0
LC78211
H 1
L 0
LC78212
H 1
L 0
LC78213
H 1
Reset input
The states of the analog switches are undefined when power is first
applied. Setting this pin low will force all switches the off state.
34
Address
A A A
1 2 3
1 0 1
1 0 1
0 1 1
0 1 1
1 1 1
1 1 1
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