MAX4356 Maxim, MAX4356 Datasheet - Page 29

• Manufacturer Part Number: MAX4356
• Description: The MAX4356 is a 16 x 16 highly integrated video crosspoint switch matrix with input and output buffers and On-Screen Display (OSD) Insertion
• Manufacturer: Maxim

The MAX4356 is a highly integrated 16
ing video crosspoint switch matrix. All inputs and out-
puts are buffered, with all outputs able to drive
standard 75 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).
In the Functional Diagram, the signal path of the
MAX4356 is from the inputs (IN0–IN15), through the
switching matrix, buffered by the output amplifiers, and
presented at the output terminals (OUT0–OUT15). The
other functional blocks are the serial interface and con-
trol logic. Each of the functional blocks is described in
detail below.
The MAX4356 outputs are high-speed voltage feed-
back amplifiers capable of driving 150
minated) loads. The gain, A
selectable through programming bit 4 of the serial con-
trol word. Amplifier compensation is automatically opti-
with On-Screen Display Insertion and I/O Buffers
16 x 16 Nonblocking Video Crosspoint Switch
______________________________________________________________________________________
Detailed Description
RESET
UPDATE
SCLK
IN15
DIN
IN0
IN1
IN2
CE
V
*A
V
= +1V/V or +2V/V, is
POWER-ON
= +1V/V OR +2V/V
MAX4356
A0-A3 MODE
RESET
INTERFACE
Analog Outputs
SERIAL
DISABLE ALL OUTPUTS
(75
SHUTDOWN
THERMAL
16 nonblock-
SWITCH MATRIX
MATRIX REGISTER
UPDATE REGISTER
DECODE LOGIC
back-ter-
LATCHES
16 x 16
96 BITS
16 BITS
256 16
OSDFILL0
OSDKEY0
OSDFILL1
mized to maximize the bandwidth for each gain selec-
tion. Each output can be individually enabled and dis-
abled through bit 5 of the serial control word. When
disabled, the output is high impedance, presenting typ-
ically a 4k
multiple outputs to be connected together in building
large arrays. On power-up (or asynchronous RESET),
all outputs are initialized in the disabled state to avoid
output conflicts in large array configurations. The pro-
gramming and operation of the MAX4356 is output
referred. Outputs are configured individually to connect
to any one of the 16 analog inputs, programmed to the
desired gain (A
high-impedance state.
The MAX4356 offers 16 analog input channels. Each
input is buffered before the crosspoint switch matrix,
allowing one input to cross-connect to up to 16 outputs.
The input buffers are voltage feedback amplifiers with
high input impedance and low-input bias current. This
allows the use of very simple input clamp circuits.
OSDKEY1
MUX
OSD
2:1
OSDFILL15
OSDKEY15
16
A
A
A
A
load, and 3pF output capacitance, allowing
V
V
V
V
*
*
*
*
V
= +1V/V or +2V/V), or disabled in a
Functional Diagram
OUT0
OUT1
OUT2
OUT15
V
V
AGND
DGND
DOUT
AOUT
V
CC
EE
DD
Analog Inputs
29