X93256_08 Datasheet, PDF (5/7 Pages) Intersil Corporation – Dual Digitally Controlled Potentiometers(XDCPs™)

X93256
AC Operating Characteristics Over recommended operating conditions, unless otherwise specified. In the table, CS, INC, U/D, R_H and
R_L are used to refer to either CS₁ or CS₂, etc. (Continued)
SYMBOL
PARAMETER
MIN
(Note 7)
TYP
(Note 4)
MAX
(Note 7)
UNIT
t_lC
t_CPH
t_CPH
t_CYC
t_R, t_F
(Note 5)
INC Inactive to CS Inactive
CS Deselect Time (No store)
CS Deselect Time (Store)
INC Cycle Time
INC Input Rise and Fall time
1
µs
250
ns
10
ms
2
µs
500
µs
t_R V_CC VCC Power-up Rate
(Note 5)
0.2
50
V/ms
t_WR
Store Cycle
5
10
ms
AC Timing
CS
t_CI
INC
t_CYC
t_IL
t_IH
t_IC
t_ID
t_DI
(STORE)
t_CPH
90% 90%
10%
t_F
t_R
U/D
Note: CS, INC, U/D, R_H and R_L are used to refer
to either CS₁ or CS₂, etc.
Power-up and Power-down Requirements
There are no restrictions on the power-up or power-down
conditions of V_CC and the voltages applied to the
potentiometer pins provided that V_CC is always more
positive than or equal to V_H and V_L, i.e., V_CC ≥ V_H,V_L. The
V_CC ramp rate specification is always in effect.
Pin Descriptions
In the text, CS, INC, U/D, R_H, R_W, and R_L are used to refer
to either CS₁ or CS₂, etc. Note: These signals can be
applied independently or at the same time.
R_H and R_L
The R_H and R_L pins of the X93256 are equivalent to the
fixed terminals of a mechanical potentiometer. The minimum
voltage is V_SS and the maximum is V_CC. The terminology of
R_H and R_L references the relative position of the terminal in
relation to wiper movement direction selected by the U/D
input per potentiometer.
R_W
The R_W pin of the X93256 is the wiper terminal of the
potentiometer, which is equivalent to the movable terminal of
a mechanical potentiometer.
5
Up/Down (U/D)
The U/D input controls the direction of a single
potentiometer’s wiper movement and whether the counter is
incremented or decremented.
Increment (INC)
The INC input is negative-edge triggered. Toggling INC will
move the wiper and either increment or decrement the
pertaining potentiometer’s counter in the direction indicated
by the logic level on the pertaining potentiometer’s U/D
input.
Chip Select (CS)
A potentiometer is selected when the pertaining CS input is
LOW. Its current counter value is stored in nonvolatile memory
when the pertaining CS is returned HIGH while the pertaining
INC input is also HIGH. After the store operation is complete
the affected potentiometer will be placed in the low power
standby mode until the potentiometer is selected once again.
Principles of Operation
There are multiple sections for each potentiometer in the
X93256: an input control, a counter and decode section; the
nonvolatile memory; and a resistor array. Each input control
FN8188.2
February 1, 2008