Datasheet

Detailed Description
Digital Interface Operation
The MAX5407 has two modes of operation when the seri-
al interface is active: increment and decrement mode.
The serial interface is only active when CS is high.
The CS and U/D inputs control the position of the wiper
along the resistor array. When CS transitions from low
to high, the part will go into increment mode if U/D is
high and into decrement mode if U/D is low. Once the
mode is set, the device will remain in that mode until CS
goes low again. A low-to-high transition at the U/D pin
will increment or decrement the wiper position depend-
ing on the mode (Figures 1 and 2).
When the CS input transitions to low (serial interface
inactive), the value of the counter is stored and the
wiper position is maintained.
MAX5407
32-Tap Audio Logarithmic Taper
Digital Potentiometer
_______________________________________________________________________________________ 5
W
U/D
CS
t
CU
t
IW
t
IC
t
IL
t
CI
t
IH
NOTE: W IS NOT A DIGITAL SIGNAL. IT REPRESENTS THE WIPER TRANSITIONING.
W
NOTE: W IS NOT A DIGITAL SIGNAL. IT REPRESENTS THE WIPER TRANSITIONING.
U/D
CS
t
IH
t
CI
t
CU
t
IL
t
IC
t
IW
Figure 1. Serial Interface Timing Diagram, Increment Mode
Figure 2. Serial Interface Timing Diagram, Decrement Mode