CAT521 Datasheet, PDF (1/13 Pages) Catalyst Semiconductor – 8-Bit Digital POT With Independent Reference Inputs

Not Recommended for New Design
CAT521
Configured Digitally Programmable Potentiometer (DPP™):
Programmable Voltage Applications
FEATURES
„ 8-bit DPP configured as a programmable
voltage source in DAC-like applications
„ Buffered wiper output
„ Non-volatile NVRAM memory wiper storage
„ Output voltage range includes both supply rails
„ 1 LSB accuracy, high resolution
„ Serial Microwire-like interface
„ Single supply operation: 2.7V – 5.5V
„ Setting read-back without effecting outputs
For Ordering Information details, see page 12.
APPLICATIONS
„ Automated product calibration
„ Remote control adjustment of equipment
„ Offset, gain and zero adjustments in self-
calibrating and adaptive control systems
„ Tamper-proof calibrations
„ DAC (with memory) substitute
PIN CONFIGURATION
PDIP 14-Lead (L)
SOIC 14-Lead (W)
V_DD 1
CLK 2
14 V_REFH
13 NC
RDY/¯B¯S¯Y¯ 3
12 V_OUT
CS 4 ^CAT521 11 NC
DI 5
10 NC
DO 6
PROG 7
8 V_REFL
8 GND
DESCRIPTION
The CAT521 is a 8-bit digitally-programmable poten-
tiometer (DPP™) configured for programmable voltage
and DAC-like applications. Intended for final calibration
of products such as camcorders, fax machines and
cellular telephones on automated high volume
production lines, it is also well suited for self-calibrating
systems and for applications where equipment which
requires periodic adjustment is either difficult to access
or in a hazardous environment.
The programmable DPP has an output voltage range
which includes both supply rails. The wiper is buffered
by a rail to rail op amp. The wiper setting, stored in
non-volatile NVRAM memory, is not lost when the
device is powered down and is automatically
reinstated when power is returned. The wiper can be
dithered to test new output values without effecting
the stored settings and stored settings can be read
back without disturbing the DPP’s output.
The CAT521 is controlled with a simple 3-wire,
Microwire like serial interface. A Chip Select pin
allows several devices to share a common serial
interface. Communication back to the host controller is
via a single serial data line thanks to the CAT521 Tri-
Stated Data Output pin. A RDY/¯B¯S¯Y¯ output working in
concert with an internal low voltage detector signals
proper operation of the non-volatile NVRAM memory
Erase/Write cycle.
The CAT521 is available in 0°C to 70°C commercial
and -40°C to 85°C industrial operating temperature
ranges. Both 14-pin plastic DIP and surface mount
packages are available.
© 2008 SCILLC. All rights reserved.
1
Characteristics subject to change without notice
Doc. No. MD-2003 Rev. I