MAX4357 Maxim, MAX4357 Datasheet - Page 29

• Manufacturer Part Number: MAX4357
• Description: The MAX4357 is a 32 x 16 highly integrated video crosspoint switch matrix with input and output buffers
• Manufacturer: Maxim

The MAX4357 is a highly integrated 32
ing video crosspoint switch matrix. All inputs and out-
puts are buffered, with all outputs able to drive
standard 75Ω reverse-terminated video loads.
A 3-wire interface programs the switch matrix and ini-
tializes with a single update signal. The unique serial
interface operates in one of two modes, Complete
Matrix Mode (Mode 1) or Individual Output Address
Mode (Mode 0).
The signal path of the MAX4357 is from the buffered
inputs (IN0–IN31), through the switching matrix,
buffered by the output amplifiers, and presented at the
outputs (OUT0–OUT15) ( Functional Diagram ). The
other functional blocks are the serial interface and con-
trol logic. Each of the functional blocks is described in
detail in the sections following.
32 x 16 Nonblocking Video Crosspoint Switch
RESET
UPDATE
______________________________________________________________________________________
SCLK
IN31
DIN
IN0
IN1
IN2
CE
Detailed Description
POWER-ON
MAX4357
A0-A3 MODE
RESET
INTERFACE
SERIAL
DISABLE ALL OUTPUTS
SHUTDOWN
THERMAL

16 nonblock-
SWITCH MATRIX
MATRIX REGISTER
UPDATE REGISTER
DECODE LOGIC
LATCHES
32 x 16
112 BITS
16 BITS
512 16
The MAX4357 outputs are high-speed amplifiers capa-
ble of driving 150Ω (75Ω back-terminated) loads. The
gain, A
gramming bit 5 of the serial control word. Amplifier com-
pensation is automatically optimized to maximize the
bandwidth for each gain selection. Each output can be
individually enabled and disabled via bit 6 of the serial
control word. When disabled, the output is high imped-
ance presenting typically 4kΩ load, and 3pF output
capacitance, allowing multiple outputs to be connected
together for building large arrays. On power-up (or asyn-
chronous RESET) all outputs are initialized in the dis-
abled state to avoid output conflicts in large array
configurations. The programming and operation of the
MAX4357 is output referred. Outputs are configured indi-
vidually to connect to any one of the 32 analog inputs,
programmed to the desired gain (A
and enabled or disabled in a high-impedance state.
V
= +1V/V or +2V/V, is selectable through pro-
16
*A
A
A
A
A
V
V
V
V
V
with I/O Buffers
= +1V/V OR +2V/V
*
*
*
*
Functional Diagram
OUT0
OUT1
OUT2
OUT15
V
V
AGND
DGND
DOUT
AOUT
V
CC
EE
DD
V
Analog Outputs
= +1V/V or +2V/V),
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