
_______________General Description
The MAX456 is the first monolithic CMOS 8 x 8 video
crosspoint switch that significantly reduces component
count, board space, and cost. The crosspoint switch
contains a digitally controlled matrix of 64 T-switches
that connect eight video input signals to any, or all, out-
put channels. Each matrix output connects to eight
internal, high-speed (250V/s), unity-gain-stable buffers
capable of driving 400
and 20pF to ±1.3V. For appli-
cations requiring increased drive capability, the
MAX456 outputs can be connected directly to two
MAX470 quad, gain-of-two video buffers, which are
capable of driving 75
loads.
Three-state output capability and internal, programma-
ble active loads make it feasible to parallel multiple
MAX456s and form larger switch matrices.
In the 40-pin DIP package, crosstalk (70dB at 5MHz) is
minimized, and board area and complexity are simpli-
fied by using a straight-through pinout. The analog
inputs and outputs are on opposite sides, and each
channel is separated by a power-supply line or quiet
digital logic line.
________________________Applications
Video Test Equipment
Video Security Systems
Video Editing
____________________________Features
o Routes Any Input Channel to Any Output Channel
o Switches Standard Video Signals
o Serial or Parallel Digital Interface
o Expandable for Larger Switch Matrices
o 80dB All-Channel Off Isolation at 5MHz
o 8 Internal Buffers with:
250V/s Slew Rate, Three-State Output Capability,
Power-Saving Disable Feature, 35MHz Bandwidth
______________Ordering Information
Ordering Information continued on last page.
* Dice are specified at TA = +25°C, DC parameters only.
MAX456
8 x 8 Video Crosspoint Switch
________________________________________________________________
Maxim Integrated Products
1
40
39
38
37
36
35
34
33
32
31
1
2
3
4
5
6
7
8
9
10
V+
OUT0
D2
OUT1
A1
A2
D0/SER IN
D1/SER OUT
TOP VIEW
MAX456
D3
OUT2
V-
OUT3
LOAD
IN1
A0
IN0
AGND
OUT4
DGND
IN2
30
29
28
27
26
25
24
23
22
21
AGND
OUT5
AGND
OUT6
V+
OUT7
CE
LATCH
WR
11
12
13
14
15
16
17
18
19
20
EDGE/LEVEL
IN4
DGND
IN3
SER/PAR
IN6
V+
IN5
V-
IN7
DIP
PLCC on last page
_________________Pin Configurations
OUTPUT
SELECT
8 X 8
T-SWITCH
MATRIX
MAX470
A2
8 INPUT CHANNELS
A1
A0
D3
D2
D1/SER OUT
D0/SER IN
INPUT
SELECT
OR
SERIAL
I/O
MAX456
LATCH
WR
75
75
AV = 2
MAX470
AV = 2
________Typical Application Circuit
Call toll free 1-800-998-8800 for free samples or literature.
19-2858; Rev 2; 2/94
PART
TEMP. RANGE
PIN-PACKAGE
MAX456CPL
0°C to +70°C
40 Plastic DIP
MAX456CQH
0°C to +70°C
44 PLCC
MAX456C/D
0°C to +70°C
Dice*