Figure 6. Detailed Serial-Interface Timing Diagram
Power
-
Down Lockout
(PDL)
Drive power-down lockout, PDL, low to disable software
shutdown. When in shutdown, transitioning PDL from
high to low wakes up the device with the output set to
the state prior to shutdown. Use PDL to asynchronously
wake up the device.
Daisy Chaining Devices
The MAX5500/MAX5501 can be daisy chained by con-
necting DOUT of one device to DIN of another device
(Figure 7).
Each DOUT output of the MAX5500/MAX5501 includes
an internal active pullup. The sink/source capability of
DOUT determines the time required to discharge/charge
a capacitive load. See the serial-data-out V
OH
and V
OL
specifications in the
Electrical Characteristics.
Figure 8 shows an alternate method of connecting sev-
eral MAX5500/MAX5501 devices. In this configuration,
the data bus is common to all devices. Data is not shift-
ed through a daisy chain. More I/O lines are required in
this configuration because a dedicated chip-select
input (CS) is required for each IC.
