Preliminary Information
CAT5115
32-Tap Digitally Programmable Potentiometer (DPP™)
FEATURES
s
32-position, linear-taper potentiometer
s
Low power CMOS technology
s
Single supply operation: 2.5V-5.5V
s
Increment up/down serial interface
s
Resistance values: 10kΩ, 50kΩ and 100kΩ
Ω
Ω
Ω
s
Available in PDIP, SOIC, TSSOP and MSOP packages
H
GEN
FR
ALO
EE
LE
APPLICATIONS
s
Automated product calibration
s
Remote control adjustments
s
Offset, gain and zero control
s
Tamper-proof calibrations
A
D
F
R
E
E
TM
s
Contrast, brightness and volume controls
s
Motor controls and feedback systems
s
Programmable analog functions
DESCRIPTION
The CAT5115 is a single digitally programmable
potentiometer (DPP™) designed as a electronic
replacement for mechanical potentiometers and trim
pots. Ideal for automated adjustments on high volume
production lines, they are also well suited for
applications where equipment requiring periodic
adjustment is either difficult to access or located in a
hazardous or remote environment.
The CAT5115 contains a 32-tap series resistor array
connected between two terminals R
H
and R
L
. An up/
down counter and decoder that are controlled by three
input pins, determines which tap is connected to the
wiper, R
W
. The wiper is always set to the mid point, tap
15 at power up. The tap position is not stored in memory.
Wiper-control of the CAT5115 is accomplished with
three input control pins,
CS,
U/D, and
INC.
The
INC
input increments the wiper in the direction which is
determined by the logic state of the U/D input. The
CS
input is used to select the device.
The digitally programmable potentiometer can be
used as a three-terminal resistive divider or as a
two-terminal variable resistor. DPPs bring variability and
programmability to a wide variety of applications
including control, parameter adjustments, and
signal processing.
For a pin-compatible device that recalls a stored tap
position on power-up refer to the CAT5114 data sheet.
FUNCTIONAL DIAGRAM
Vcc
(Supply Voltage)
U/D
INC
CS
5-BIT
UP/DOWN
COUNTER
31
R
H
/ V
H
V
H
/R
H
30
R
H
/ V
H
UP/DOWN
(U/D)
INCREMENT
(INC)
DEVICE SELECT
(CS)
POR
29
Control
and
Memory
R
W
/ V
W
ONE
28
OF
THIRTY TWO
DECODER
TRANSFER
GATES
RESISTOR
ARRAY
V
W
/ R
W
2
R
L
/ V
L
Vcc
CONTROL
CIRCUITRY
1
GND
GENERAL
V
SS
0
R
L
/ V
L
R
W
/ V
W
V
L
/ R
L
GENERAL
DETAILED
ELECTRONIC POTENTIOMETER
IMPLEMENTATION
© 2004 by Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
1
Doc. No. 2117, Rev. E
CAT5115
PIN CONFIGURATION
DIP Package (P, L)
INC
U/D
RH
GND
1
2
3
4
8
7
6
5
V
CC
CS
RL
RW
PIN FUNCTIONS
TSSOP Package (U, Y)
CS
V
CC
INC
U/D
1
2
3
4
8
7
6
5
R
L
R
W
GND
R
H
Pin Name
INC
U/D
R
H
GND
R
W
Function
Increment Control
Up/Down Control
Potentiometer High Terminal
Ground
Potentiometer Wiper Terminal
Potentiometer Low Terminal
Chip Select
Supply Voltage
SOIC Package (S, V)
INC
U/D
RH
GND
1
2
3
4
8
7
6
5
V
CC
CS
RL
RW
MSOP Package (R, Z)
INC
U/D
R
H
GND
1
2
3
4
8
7
6
5
V
CC
CS
R
L
R
W
R
L
CS
V
CC
PIN DESCRIPTIONS
INC:
INC
Increment Control Input
The
INC
input moves the wiper in the up or down
direction determined by the condition of the U/D input.
U/D
: Up/Down Control Input
D
The U/D input controls the direction of the wiper
movement. When in a high state and
CS
is low, any high-
to-low transition on
INC
will cause the wiper to move one
increment toward the R
H
terminal. When in a low state
and
CS
is low, any high-to-low transition on
INC
will
cause the wiper to move one increment towards the
R
L
terminal.
R
H:
High End Potentiometer Terminal
R
H
is the high end terminal of the potentiometer. It is not
required that this terminal be connected to a potential
greater than the R
L
terminal. Voltage applied to the R
H
terminal cannot exceed the supply voltage, V
CC
or go
below ground, GND.
R
W
: Wiper Potentiometer Terminal
R
W
is the wiper terminal of the potentiometer. Its position
on the resistor array is controlled by the control inputs,
INC,
U/D and
CS.
Voltage applied to the R
W
terminal cannot
exceed the supply voltage, V
CC
or go below ground, GND.
R
L
: Low End Potentiometer Terminal
R
L
is the low end terminal of the potentiometer. It is not
required that this terminal be connected to a potential
less than the R
H
terminal. Voltage applied to the R
L
terminal cannot exceed the supply voltage, V
CC
or go
below ground, GND. R
L
and R
H
are electrically
interchangeable.
CS:
CS
Chip Select
The chip select input is used to activate the control input
of the CAT5115 and is active low. When in a high
state, activity on the
INC
and U/D inputs will not
affect or change the position of the wiper.
DEVICE OPERATION
The CAT5115 operates like a digitally controlled
potentiometer with R
H
and R
L
equivalent to the high
and low terminals and R
W
equivalent to the mechanical
potentiometer's wiper. There are 32 available tap
positions including the resistor end points, R
H
and R
L
.
There are 31 resistor elements connected in series
between the R
H
and R
L
terminals. The wiper terminal is
connected to one of the 32 taps and controlled by three
inputs,
INC,
U/D and
CS.
These inputs control a five-bit
up/down counter whose output is decoded to select the
wiper position.
With
CS
set LOW the CAT5115 is selected and will
respond to the U/D and
INC
inputs. HIGH to LOW
transitions on
INC
wil increment or decrement the
wiper (depending on the state of the U/D input and five-
bit counter). The wiper, when at either fixed terminal,
acts like its mechanical equivalent and does not move
beyond the last position. When the CAT5115 is powered-
down, the wiper position is reset. When power is restored,
the counter is set to the mid point, tap 15.
Doc. No. 2117, Rev. E
2
CAT5115
OPERATION MODES
INC
High to Low
High to Low
X
CS
Low
Low
High
U/D
High
Low
X
Operation
Wiper toward H
Wiper toward L
Standby
C
L
C
H
R
H
R
wi
R
W
C
W
R
L
Potentiometer
Equivalent Circuit
ABSOLUTE MAXIMUM RATINGS
Supply Voltage
V
CC
to GND ...................................... –0.5V to +7V
Inputs
CS
to GND .............................–0.5V to V
CC
+0.5V
INC
to GND ............................–0.5V to V
CC
+0.5V
U/D to GND ............................–0.5V to V
CC
+0.5V
H to GND ................................–0.5V to V
CC
+0.5V
L to GND ................................–0.5V to V
CC
+0.5V
W to GND ............................... –0.5V to V
CC
+0.5V
RELIABILITY CHARACTERISTICS
Symbol
V
ZAP(1)
I
LTH(1)(2)
T
DR
N
END
Operating Ambient Temperature
Industrial (‘I’ suffix) ...................... – 40°C to +85°C
Junction Temperature ..................................... +150°C
Storage Temperature ....................... –65°C to +150°C
Lead Soldering (10 sec max) .......................... +300°C
* Stresses above those listed under Absolute Maximum Ratings may
cause permanent damage to the device. Absolute Maximum Ratings
are limited values applied individually while other parameters are
within specified operating conditions, and functional operation at any
of these conditions is NOT implied. Device performance and reliability
may be impaired by exposure to absolute rating conditions for extended
periods of time.
Parameter
ESD Susceptibility
Latch-Up
Data Retention
Endurance
Test Method
MIL-STD-883, Test Method 3015
JEDEC Standard 17
MIL-STD-883, Test Method 1008
MIL-STD-883, Test Method 1003
Min
2000
100
100
1,000,000
Typ
Max
Units
Volts
mA
Years
Stores
DC Electrical Characteristics: V
CC
= +2.5V to +5.5V unless otherwise specified
Power Supply
Symbol Parameter
Conditions
Min
V
CC
I
CC1
I
CC2
ISB
1 (2)
Operating Voltage Range
Supply Current (Increment)
Supply Current (Write)
Supply Current (Standby)
V
CC
= 5.5V, f = 1MHz, I
W
=0
V
CC
= 5.5V, f = 250kHz, I
W
=0
Programming, V
CC
= 5.5V
V
CC
= 3V
CS=V
CC
-0.3V
U/D, INC=V
CC
-0.3V or GND
2.5
—
—
—
—
—
Typ
—
—
—
—
—
—
Max
5.5
100
50
1
500
1
Units
V
µA
mA
µA
µA
Logic Inputs
Symbol
I
IH
I
IL
V
IH1
V
IL1
V
IH2
V
IL2
NOTES:
(1)
(2)
(3)
(4)
Parameter
Input Leakage Current
Input Leakage Current
TTL High Level Input Voltage
TTL Low Level Input Voltage
CMOS High Level Input Voltage
CMOS Low Level Input Voltage
Conditions
V
IN
= V
CC
V
IN
= 0V
4.5V
≤
V
CC
≤
5.5V
2.5V
≤
V
CC
≤
5.5V
Min
—
—
2
0
V
CC
x 0.7
-0.3
Typ
—
—
—
—
—
—
Max
10
–10
V
CC
0.8
V
CC
+ 0.3
V
CC
x 0.2
Units
µA
µA
V
V
V
V
This parameter is tested initially and after a design or process change that affects the parameter.
Latch-up protection is provided for stresses up to 100mA on address and data pins from –1V to V
CC
+ 1V
I
W
=source or sink
These parameters are periodically sampled and are not 100% tested.
3
Doc. No. 2117, Rev. E
CAT5115
Potentiometer Parameters
Symbol
R
POT
Parameter
Potentiometer Resistance
Conditions
-10 Device
-50 Device
-00 Device
Pot Resistance Tolerance
V
RH
V
RL
INL
DNL
R
Wi
I
W
TC
RPOT
TC
RATIO
V
N
C
H
/C
L
/C
W
fc
Voltage on R
H
pin
Voltage on R
L
pin
Resolution
Integral Linearity Error
Differential Linearity Error
Wiper Resistance
Wiper Current
TC of Pot Resistance
Ratiometric TC
Noise
Potentiometer Capacitances
Frequency Response
Passive Attenuator, 10kΩ
100kHz / 1kHz
8/24
8/8/25
1.7
300
20
I
W
≤
2µA
I
W
≤
2µA
V
CC
= 5V, I
W
= 1mA
V
CC
= 2.5V, I
W
= 1mA
0
0
3.2
0.5
0.25
1
0.5
400
1
1
Min
Typ
10
50
100
±
20
V
CC
V
CC
%
V
V
%
LSB
LSB
Ω
kΩ
mA
ppm/
o
C
ppm/
o
C
nV/√H
z
pF
MHz
kΩ
Max
Units
Doc. No. 2117, Rev. E
4
CAT5115
AC CONDITIONS OF TEST
V
CC
Range
Input Pulse Levels
Input Rise and Fall Times
Input Reference Levels
2.5V
≤
V
CC
≤
5.5V
0.2V
CC
to 0.7V
CC
10ns
0.5V
CC
AC OPERATING CHARACTERISTICS:
V
CC
= +2.5V to +5.5V, V
H
= V
CC
, V
L
= 0V
, unless otherwise specified
Symbol
t
CI
t
DI
t
ID
t
IL
t
IH
t
IC
t
CPH
t
CPH
t
IW
t
CYC
t
R,
t
F(2)
t
PU(2)
t
WR
Parameter
CS
to INC Setup
U/D to
INC
Setup
U/D to
INC
Hold
INC
LOW Period
INC
HIGH Period
INC
Inactive to
CS
Inactive
CS
Deselect Time (NO STORE)
CS
Deselect Time (STORE)
INC
to V
OUT
Change
INC
Cycle Time
INC
Input Rise and Fall Time
Power-up to Wiper Stable
Store Cycle
Min
100
50
100
250
250
1
100
10
—
1
—
—
—
Typ
(1)
—
—
—
—
—
—
—
—
1
—
—
—
5
Max
—
—
—
—
—
—
—
—
5
—
500
1
10
Units
ns
ns
ns
ns
ns
µs
ns
ms
µs
µs
µs
msec
ms
A. C. TIMING
CS
t
CYC
t
IL
t
IH
(store)
t
CI
INC
t
IC
t
CPH
90%
10%
90%
tDI
tID
U/D
t
F
t
R
t
IW
RW
MI (3)
(1) Typical values are for T
A
=25
o
C and nominal supply voltage.
(2) This parameter is periodically sampled and not 100% tested.
(3) MI in the A.C. Timing diagram refers to the minimum incremental change in the W output due to a change in the wiper position.
5
Doc. No. 2117, Rev. E