MAX4586/MAX4587
nizes its address (01101A10), it acknowledges that it is
ready for further communication by pulling the SDA line
low for one clock period.
3-Wire Serial Interface
The MAX4587 3-wire serial interface is SPI/QSPI/
MICROWIRE compatible. An active-low chip-select
(CS) input enables the device to receive data for the
serial input (DIN). Data is clocked in on the rising edge
of the serial-clock (SCLK) signal. A total of 8 bits is
needed in each write cycle. The first bit clocked into
the MAX4587 is the command byte’s MSB, and the last
bit clocked in is the data byte’s LSB. The first four bits
of the command byte are “don’t care.” While shifting
data, the device remains in its original configuration.
After all eight bits are clocked into the input shift regis-
ter, a rising edge on CS latches the data into the
MAX4587 internal registers, initiating the device’s
change of state. Figures 3 and 4 detail the 3-wire proto-
col, and Table 1 details the command byte format.
Addressable Serial Interface
To program several MAX4587s individually using a sin-
gle processor, connect DIN of each MAX4587 together
and control CS on each MAX4587 separately. To select
a particular device, drive the corresponding CS low,
clock in the 8-bit command, then drive CS high to exe-
cute the command. Typically, only one MAX4587 is
addressed at a time.
Power-Up State
The MAX4586/MAX4587 feature a preset power-up
state. See Table 1 to determine the power-up state of
the devices.
Serially Controlled, 4-Channel
Audio/Video Multiplexers
10 ______________________________________________________________________________________
