MAX4357 Maxim, MAX4357 Datasheet - Page 31

• 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

Drive MODE to logic low to select Mode 0. Individual
outputs are programmed via the serial interface with a
single 16-bit control word. The control word consists of
a don’t care MSB, the chip address bits, output
address bits, an output enable/disable bit, an output
gain-set bit, and input address bits (Table 2 through
Table 6, and Figure 2).
In Mode 0, data at DIN passes directly to DOUT
through the data routing gate (Figure 3). In this configu-
ration, the 16-bit control word is simultaneously sent to
all chips in an array of up to 16 addresses.
Drive MODE to logic high to select Mode 1. A single
112-bit control word, consisting of sixteen 7-bit control
words, programs all outputs. The 112-bit control word’s
first 7-bit control word (MSBs) programs output 15, and
Figure 2. Serial Interface Block Diagram
Individual Output Address Mode (MODE = 0)
32 x 16 Nonblocking Video Crosspoint Switch
Complete Matrix Mode (MODE = 1)
______________________________________________________________________________________
DIN
MODE
SCLK
CE
MODE
SCLK
CE
OUTPUT ADDRESS DECODE
EN
UPDATE
SWITCH MATRIX
16-BIT INDIVIDUAL OUTPUT
112-BIT COMPLETE MATRIX MODE REGISTER
ADDRESS MODE REGISTER
CHIP ADDRESS
512
11
11
112-BIT PARALLEL LATCH
A0–A3
SWITCH DECODE
7
the last 7-bit control word (LSBs) programs output 0
(Table 7 and Figures 4 and 5). Data clocked into the
112-bit Complete Matrix Mode register is latched on the
falling edge of UPDATE, and the outputs are immedi-
ately updated.
Complete Matrix Mode (Mode = 1) is convenient for
programming the matrix at power-up. In a large matrix
consisting of many MAX4357s, all the devices can be
programmed by sending a single bit stream equal to n
x 112 bits where n is the number of MAX4357 devices
on the bus. The first 112-bit data word programs the
last MAX4357 in line (see Matrix Programming section).
The MAX4357 features an asynchronous bidirectional
RESET with an internal 20kΩ pullup resistor to V
When RESET is pulled low either by internal circuitry, or
4
4
112
7
MODE
OUTPUT ENABLE
16
1
112
AOUT
112
with I/O Buffers
MODE
B
A
ROUTING
DATA
GATE
S
MODE
Initialization String
DOUT
RESET
DD
31
.