X9448 Datasheet, PDF (1/20 Pages) Xicor Inc. – Mixed Signal with 2-Wire Interface

Mixed Signal with 2-Wire Interface
X9448
Dual Digitally Controlled Potentiometer (XDCP^™) & Voltage Comparator
FEATURES
• Two digitally controlled potentiometers and two
voltage comparators in one package
• 2-wire serial interface
• Register oriented format
—Direct read/write wiper position
—Store as many as four positions per pot
• Fast response comparator
• Enable, latch, or shutdown comparator outputs
through ACR
• Auto-recall of WCR and ACR data from R0
• Hardware write protection, WP
• Separate analog and digital/system supplies
• Direct write cell
—Endurance–100,000 data changes per bit per
register
—Register data retention–100 years
• 16-bytes of EEPROM memory
• Power saving feature and low noise
• Two 10KΩ or two 2.5KΩ potentiometers
• Resolution: 64 taps each pot
• 24-lead TSSOP and 24-lead SOIC packages
DESCRIPTION
The X9448 integrates two nonvolatile digitally con-
trolled potentiometers (XDCP) and two voltage com-
parators on a CMOS monolithic microcircuit.
The X9448 contains two resistor arrays, each com-
posed of 63 resistive elements. Between each element
and at either end are tap points accessible to the wiper
elements. The position of the wiper element on the
array is controlled by the user through the two wire
serial bus interface.
Each potentiometer has an associated voltage com-
parator. The comparator compares the external input
voltage V_NI with the wiper voltage V_W and sets the out-
put voltage level to a logic high or low.
Each resistor array and comparator has associated
with it a wiper counter register (WCR), analog control
register (ACR), and eight 6-bit data registers that can
be directly written and read by the user. The contents
of the wiper counter register controls the position of
the wiper on the resistor array. The contents of the
analog control register controls the comparator and its
output. The potentiometer is programmed with a
2-wire serial interface
BLOCK DIAGRAM
WP
SCL
SDA
A0
A1
A2
A3
Interface
and
Control
Circuitry
(R₀-R₃)_0,1
WCR_0,1
+
(R₀-R₃)_0,1
ACR_0,1
–
V_{H (0,1)}
V_{L (0,1)}
V_{W (0,1)}
V_{NI (0,1)}
V_{OUT (0,1)}
XDCP is a trademark of Xicor, Inc.
REV 1.0 6/21/00
www.xicor.com
Characteristics subject to change without notice. 1 of 20