Datasheet
MAX4584/MAX4585
_______________Detailed Description
The MAX4584/MAX4585 are serial-interface, program-
mable switches. Each device contains one normally
open (NO) single-pole/single-throw (SPST) switch and
one single-pole/double-throw (SPDT) switch. The
switches are independently controlled through the on-
chip serial interface. The MAX4584 uses a 2-wire I
2
C-
compatible serial communications protocol; the
MAX4585 uses a 3-wire SPI/QSPI/MICROWIRE-com-
patible serial communications protocol.
These devices operate from a single +2.7V to +5.5V
supply and are optimized for use with an audio fre-
quency of 20kHz and video frequencies up to 10MHz.
They feature 65Ω on-resistance, 4Ω on-resistance
matching between channels, and 5Ω on-resistance flat-
ness. Audio off-isolation is -83dB at 20kHz, and
crosstalk is at least -84dB at 20kHz. Video off-isolation
is -48dB at 10MHz, and crosstalk is at least -60dB at
10MHz.
__________Applications Information
Switch Control
The MAX4584/MAX4585 have a common command-bit
structure; the only difference between them is the inter-
face type (2-wire or 3-wire, respectively).
The command controls the open/closed states of the
various switches. Table 1 shows the configuration of
the data bits and their related switches. After a com-
mand is issued, a logic “1” in any data-bit location clos-
Serially Controlled
Audio/Video Switches
8 _______________________________________________________________________________________
Pin Description
SCL
SDA
t
LOW
t
HIGH
t
F
t
R
t
HD
,
STA
t
HD
,
DAT
t
HD
,
STA
t
SU
,
DAT
t
SU
,
STA
t
BUF
t
SU
,
STO
START CONDITIONSTOP CONDITIONREPEATED START CONDITIONSTART CONDITION
20%
70%
20%
70%
20%
70%
20%
70%
20%
70%
20%
70%
20%
70% 70%
20%
70% 70% 70%
Figure 1. 2-Wire Serial-Interface Timing Diagram
Normally Open TerminalNO1A
FUNCTION
1010
PIN
NAME
MAX4584 MAX4585
LSB+2 of the 2-Wire Serial-Interface Address Field2 A
Chip Select of the 3-Wire Serial Interface—
CS
Data Input of the 3-Wire Serial Interface—
Clock Input of the 2-Wire Serial Interface
Normally Open SPST Terminal
Ground
Data Input of the 2-Wire Serial Interface3
DIN
SCL
NO2
GND
SDA
Analog Switch SPDT Common Terminal1 COM1
Supply VoltageV+
Clock Input of the 3-Wire Serial Interface
5
SCLK
Analog Switch SPST Common Terminal
6
COM2
Normally Open TerminalNO1B
1
—
2
—
3
—
6
8
44
5—
77
9
8
9