REV 1.2 2/5/03
Characteristics subject to change without notice.
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X9116
Digitally Controlled Potentiometer (XDCP
TM
)
FEATURES
Solid-state nonvolatile
16 wiper taps
3-wire up/down serial interface
V
CC
= 2.7V and 5V
Active current < 50A max.
Standby current < 1A max.
R
TOTAL
= 10K
Packages: MSOP-8, SOIC
DESCRIPTION
The Xicor X9116 is a digitally controlled nonvolatile
potentiometer designed to be used in trimmer applica-
tions. The pot consists of 15 equal resistor segments
that connect to the wiper pin through programmable
CMOS switches. The tap position is programmed
through a 3-wire up/down serial port. The last position
of the wiper is stored in a nonvolatile memory location
which is recalled at the time of power up of the device.
The wiper moves through sequential tap positions with
inputs on the serial port. A falling edge on INC (bar)
causes the tap position to increment one position up or
down based on whether the U/D (bar) pin is held high
or low.
The X9116 can be used in many applications requiring
a variable resistance. In many cases it can replace a
mechanical trimmer and offers many advantages such
as temperature and time stability as well as the reli-
ability of a solid state solution.
BLOCK DIAGRAM
Control
and
Memory
Up/Down
(U/D)
Increment
(INC)
Device Select
(CS)
V
CC
(Supply Voltage)
V
SS
(Ground)
R
H
/V
H
R
W
/V
W
R
L
/V
L
General
R
L
R
H
0
1
2
3
*
13
14
15
R
W
-R
L
Resistance
10k
9.34k
8.68k
* k
2.08k
1.42k
760
100
A
PPLICATION
N
OTE
A V A I L A B L E
AN99 AN115 AN120 AN124 AN133 AN134
Low Noise, Low Power, Low Cost
X9116
Characteristics subject to change without notice.
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PIN DESCRIPTIONS
V
H
/R
H
and V
L
/R
L
The high (V
H
/R
H
) and low (V
L
/R
L
) terminals of the
X9116 are equivalent to the fixed terminals of a
mechanical potentiometer. The minimum voltage is
V
SS
and the maximum is V
CC
.
V
W
/R
W
R
w
/R
w
is the wiper terminal and is equivalent to the
movable terminal of a mechanical potentiometer. The
position of the wiper within the array is determined by
the control inputs. The wiper terminal series resistance
is typically 200
to 400
depending upon V
CC
.
Up/Down (U/D)
The U/D input controls the direction of the wiper move-
ment and whether the counter is incremented (up) or
decremented (down).
Increment (INC)
The INC input is negative-edge triggered. Toggling
INC will move the wiper and either increment or decre-
ment the counter in the direction indicated by the logic
level on the U/D input.
Chip Select (CS)
The device is selected when the CS input is LOW. The
current counter value is stored in nonvolatile memory
when CS is returned HIGH while the INC input is also
HIGH. After the store operation is complete the X9116
will be placed in the low power standby mode until the
device is selected once again.
PIN CONFIGURATION
PIN NAMES
PRINCIPLES OF OPERATION
There are three sections of the X9116: the input con-
trol, counter and decode section; the nonvolatile mem-
ory; and the resistor array. The input control section
operates just like an up/down counter. The output of
this counter is decoded to turn on a single electronic
switch connecting a point on the resistor array to the
wiper output. Under the proper conditions the contents
of the counter can be stored in nonvolatile memory
and retained for future use. The resistor array is com-
prised of 15 individual resistors connected in series. At
either end of the array and between each resistor is an
electronic switch that transfers the potential at that
point to the wiper pin.
The wiper, when at either fixed terminal, acts like its
mechanical equivalent and does not move beyond the
last position. That is, the counter does not wrap
around when clocked to either extreme.
The electronic switches on the device operate in a
"make before break" mode when the wiper changes
tap positions. If the wiper is moved several positions,
multiple taps are connected to the wiper for t
IW
(INC to
V
W
change). The R
TOTAL
value for the device can tem-
porarily be reduced by a significant amount if the wiper
is moved several positions.
When the device is powered-down, the last wiper posi-
tion stored will be maintained in the nonvolatile mem-
ory. When power is restored, the contents of the
memory are recalled and the wiper is set to the value
last stored.
V
H
/R
H
V
CC
INC
U/D
1
2
3
4
8
7
6
5
X9116
SOIC/MSOP
V
SS
CS
V
L
/R
L
V
W
/R
W
Symbol
Description
V
H
/R
H
High Terminal
V
W
/R
W
Wiper Terminal
V
L
/R
L
Low Terminal
V
SS
Ground
V
CC
Supply Voltage
U/D
Up/Down Control Input
INC
Increment Control Input
CS
Chip Select Input
X9116
Characteristics subject to change without notice.
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INSTRUCTIONS AND PROGRAMMING
The INC, U/D and CS inputs control the movement of
the wiper along the resistor array. With CS set LOW,
the device is selected and enabled to respond to the
U/D and INC inputs. HIGH to LOW transitions on INC
will increment or decrement (depending on the state of
the U/D input) a four bit counter. The output of this
counter is decoded to select one of 16 wiper positions
along the resistive array.
The value of the counter is stored in nonvolatile mem-
ory whenever CS transitions HIGH while the INC input
is also HIGH.
The system may select the X9116, move the wiper,
and deselect the device without having to store the lat-
est wiper position in nonvolatile memory. After the
wiper movement is performed as described above and
once the new position is reached, the system must
keep INC LOW while taking CS HIGH. The new wiper
position will be maintained until changed by the sys-
tem or until a power-up/down cycle recalls the previ-
ously stored data.
This procedure allows the system to always power-up
to a preset value stored in nonvolatile memory; then
during system operation, minor adjustments could be
made. The adjustments might be based on user pref-
erence, system parameter changes due to tempera-
ture drift, etc.
The state of U/D may be changed while CS remains
LOW. This allows the host system to enable the device
and then move the wiper up and down until the proper
trim is attained.
MODE SELECTION
SYMBOL TABLE
CS
INC
U/D
Mode
L
H
Wiper Up
L
L
Wiper Down
H
X
Store Wiper Position
H
X
X
Standby Current
L
X
No Store, Return to Standby
WAVEFORM
INPUTS
OUTPUTS
Must be
steady
Will be
steady
May change
from Low to
High
Will change
from Low to
High
May change
from High to
Low
Will change
from High to
Low
Don't Care:
Changes
Allowed
Changing:
State Not
Known
N/A
Center Line
is High
Impedance
X9116
Characteristics subject to change without notice.
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ABSOLUTE MAXIMUM RATINGS
Temperature under bias ....................65
C to +135
C
Storage temperature .........................65C to +150C
Voltage on CS, INC, U/D, V
H
/R
H
, V
L
/R
L
and V
CC
with respect to V
SS
................... 1V to +7V
V = |V
H
/R
H
V
L
/R
L
| ............................................ 5.5V
Lead temperature (soldering 10 seconds)..........300C
I
W
(10 seconds) ............................................ 10.0mA
COMMENT
Stresses above those listed under "Absolute Maximum
Ratings" may cause permanent damage to the device.
This is a stress rating only; the functional operation of
the device (at these or any other conditions above
those listed in the operational sections of this specifi-
cation) is not implied. Exposure to absolute maximum
rating conditions for extended periods may affect
device reliability.
RECOMMENDED OPERATING CONDITIONS
Temperature
Min.
Max.
Commercial
0C
+70C
Industrial
40C
+85C
Supply Voltage (V
CC
)
Limits
X9116
5V 10%
X9116-2.7
2.7V to 5.5V
POTENTIOMETER CHARACTERISTICS
(Over recommended operating conditions unless otherwise stated)
Notes:
(1) Absolute linearity is utilized to determine actual wiper voltage versus expected voltage = (V
w(n)
(actual)V
w(n)
(expected)) = 1
Ml Maximum.
(2) Relative linearity is a measure of the error in step size between taps = V
W(n+1)
[V
w(n)
+ Ml] = 0.2 Ml.
(3) 1 Ml = Minimum Increment = R
TOT
/15.
Symbol
Parameter
Limits
Test Conditions/Notes
Min.
Typ.
Max.
Unit
R
TOTAL
End to end resistance variation
20
+20
%
V
VH
V
H
/R
H
terminal voltage
V
SS
V
CC
V
V
SS
=
0V
V
VL
V
L
/R
L
terminal voltage
V
SS
V
CC
V
V
SS
= 0V
Power rating
10
mW
R
TOTAL
= 10 K
R
W
Wiper resistance
200
400
I
W
= 1mA, V
CC
= 5V
R
W
Wiper resistance
400
1000
I
W
= 1mA, V
CC
= 2.7V
I
W
Wiper current
-5.0
+5.0
mA
Noise
-120
dBV
Hz Ref: 1kHz
Resolution
6
%
Absolute linearity
(1)
-1
+1
MI
(3)
V
w(n)(actual)
V
w(n)(expected)
Relative linearity
(2)
-0.2
+0.2
MI
(3)
V
w(n+1)
[V
w(n)+MI
]
R
TOTAL
temperature coefficient
300
ppm/C
Ratiometric temperature coefficient
20
ppm/C
C
H
/C
L
/C
W
Potentiometer capacitances
10/10/25
pF
See Circuit #3
X9116
Characteristics subject to change without notice.
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D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified)
Notes: (4) Typical values are for T
A
= 25C and nominal supply voltage.
(5) This parameter is periodically sampled and not 100% tested.
ENDURANCE AND DATA RETENTION
Symbol
Parameter
Limits
Unit
Test Conditions
Min.
Typ.
(4)
Max.
I
CC1
V
CC
active current (Increment)
150
A
CS = V
IL
, U/D = V
IL
or V
IH
and
INC = 0.4V/2.4V @ max. t
CYC
I
CC2
V
CC
active current (Store)
(EEPROM Store)
400
A
CS = V
IH
, U/D = V
IL
or V
IH
and
INC = V
IH
@ max. t
WR
I
SB
Standby supply current
1
A
CS = V
CC
0.3V, U/D and
INC = V
SS
or V
CC
0.3V
I
LI
CS, INC, U/D input leakage
current
10
A
V
IN
= V
SS
to V
CC
V
IH
CS, INC, U/D input HIGH voltage
2V
V
CC
+ 0.5
V
V
IL
CS, INC, U/D input LOW voltage
0.5
0.8
V
C
IN
(5)
CS, INC, U/D input capacitance
10
pF
V
CC
= 5V, V
IN
= V
SS
,
T
A
= 25C, f = 1MHz
Parameter
Min.
Unit
Minimum endurance
100,000
Data changes per bit
Data retention
100
Years
Test Circuit #1
Test Point
V
W
/R
W
V
H
/R
H
V
L
/R
L
V
S
Test Circuit #2
Force
Current
V
L
VW
V
H
/R
H
V
W
/R
W
V
L
/R
L
Test Point
Circuit #3 SPICE Macro Model
C
H
C
L
R
W
10pF
10pF
R
H
R
L
R
TOTAL
C
W
25pF
A.C. CONDITIONS OF TEST
Input pulse levels
0V to 3V
Input rise and fall times
10ns
Input reference levels
1.5V
X9116
Characteristics subject to change without notice.
6 of 11
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A.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified)
POWER UP AND DOWN REQUIREMENTS
There are no restrictions on the power-up or power-down conditions of V
CC
and the voltages applied to the potenti-
ometer pins provided that V
CC
is always more positive than or equal to V
H
, V
L
, and V
W
, i.e., V
CC
V
H
, V
L
, V
W
. The
V
CC
ramp rate spec is always in effect.
A.C. TIMING
Notes: (6) Typical values are for T
A
= 25C and nominal supply voltage.
(7) This parameter is not 100% tested.
(8) MI in the A.C. timing diagram refers to the minimum incremental change in the V
W
output due to a change in the wiper position.
Symbol
Parameter
Limits
Unit
Min.
Typ.
(6)
Max.
t
Cl
CS to INC setup
100
ns
t
lD
INC HIGH to U/D change
100
ns
t
DI
U/D to INC setup
2.9
s
t
lL
INC LOW period
1
s
t
lH
INC HIGH period
1
s
t
lC
INC inactive to CS inactive
1
s
t
CPH
CS deselect time (STORE)
10
ms
t
IW
INC to Vw change
1
5
s
t
CYC
INC cycle time
4
s
t
R,
t
F
(7)
INC input rise and fall time
500
s
t
PU
(7)
Power up to wiper stable
5
s
t
R
V
CC
(7)
V
CC
Power-up rate
15
50
mV/s
t
WR
Store cycle
5
10
ms
CS
INC
U/D
V
W
t
CI
t
IL
t
IH
t
CYC
t
ID
t
DI
t
IW
MI
(8)
t
IC
t
CPH
t
F
t
R
10%
90%
90%
(store)
X9116
Characteristics subject to change without notice.
7 of 11
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Basic Configurations of Electronic Potentiometers
Basic Circuits
V
R
V
W
/R
W
V
R
I
Three terminal potentiometer;
variable voltage divider
Two terminal variable resistor;
variable current
V
H
V
L
Cascading Techniques
Buffered Reference Voltage
+
+5V
R
1
+V
5V
V
W
V
REF
V
OUT
OP-07
V
W
V
W
/R
W
+V
+V
+V
X
(a)
(b)
V
OUT
= V
W
/R
W
Noninverting Amplifier
+
V
S
V
O
R
2
R
1
V
O
= (1+R
2
/R
1
)V
S
LM308A
Voltage Regulator
R
1
R
2
I
adj
V
O
(REG) = 1.25V (1+R
2
/R
1
)+Iadj R
2
V
O
(REG)
V
IN
317
Comparator with Hysteresis
V
UL
= {R
1
/(R
1
+R
2
)} V
O
(max)
V
LL
= {R
1
/(R
1
+R
2
)} V
O
(min)
+
V
S
V
O
R
2
R
1
}
}
LT311A
+5V
5V
(for additional circuits see AN115)
X9116
Characteristics subject to change without notice.
8 of 11
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PACKAGING INFORMATION
0.118 0.002
(3.00 0.05)
0.040 0.002
(1.02 0.05)
0.150 (3.81)
Ref.
0.193 (4.90)
0.030 (0.76)
0.036 (0.91)
0.032 (0.81)
0.007 (0.18)
0.005 (0.13)
0.008 (0.20)
0.004 (0.10)
0.0216 (0.55)
7 Typ.
R 0.014 (0.36)
0.118 0.002
(3.00 0.05)
0.012 + 0.006 / -0.002
(0.30 + 0.15 / -0.05)
0.0256 (0.65) Typ.
8-Lead Miniature Small Outline Gull Wing Package Type M
NOTE:
1. ALL DIMENSIONS IN INCHES AND (MILLIMETERS)
0.220"
0.0256" Typical
0.025"
Typical
0.020"
Typical
8 Places
FOOTPRINT
Ref.
X9116
Characteristics subject to change without notice.
9 of 11
REV 1.2 2/5/03
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PACKAGING INFORMATION
0.118 0.002
(3.00 0.05)
0.040 0.002
(1.02 0.05)
0.150 (3.81)
Ref.
0.193 (4.90)
0.030 (0.76)
0.036 (0.91)
0.032 (0.81)
0.007 (0.18)
0.005 (0.13)
0.008 (0.20)
0.004 (0.10)
0.0216 (0.55)
7 Typ.
R 0.014 (0.36)
0.118 0.002
(3.00 0.05)
0.012 + 0.006 / -0.002
(0.30 + 0.15 / -0.05)
0.0256 (0.65) Typ.
8-Lead Miniature Small Outline Gull Wing Package Type M
NOTE:
1. ALL DIMENSIONS IN INCHES AND (MILLIMETERS)
0.220"
0.0256" Typical
0.025"
Typical
0.020"
Typical
8 Places
FOOTPRINT
Ref.
X9116
Characteristics subject to change without notice.
10 of 11
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PACKAGING INFORMATION
0.150 (3.80)
0.158 (4.00)
0.228 (5.80)
0.244 (6.20)
0.014 (0.35)
0.019 (0.49)
Pin 1
Pin 1 Index
0.010 (0.25)
0.020 (0.50)
0.050 (1.27)
0.188 (4.78)
0.197 (5.00)
0.004 (0.19)
0.010 (0.25)
0.053 (1.35)
0.069 (1.75)
(4X) 7
0.016 (0.410)
0.037 (0.937)
0.0075 (0.19)
0.010 (0.25)
0 - 8
X 45
8-Lead Plastic Small Outline Gull Wing Package Type S
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
0.250"
0.050"Typical
0.050"
Typical
0.030"
Typical
8 Places
FOOTPRINT
X9116
Characteristics subject to change without notice.
11 of 11
LIMITED WARRANTY
Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc. makes no warranty,
express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement.
Xicor, Inc. makes no warranty of merchantability or fitness for any purpose. Xicor, Inc. reserves the right to discontinue production and change specifications and prices
at any time and without notice.
Xicor, Inc. assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xicor, Inc. product. No other circuits, patents, or licenses are implied.
TRADEMARK DISCLAIMER:
Xicor and the Xicor logo are registered trademarks of Xicor, Inc. AutoStore, Direct Write, Block Lock, SerialFlash, MPS, and XDCP are also trademarks of Xicor, Inc. All
others belong to their respective owners.
U.S. PATENTS
Xicor products are covered by one or more of the following U.S. Patents: 4,326,134; 4,393,481; 4,404,475; 4,450,402; 4,486,769; 4,488,060; 4,520,461; 4,533,846;
4,599,706; 4,617,652; 4,668,932; 4,752,912; 4,829,482; 4,874,967; 4,883,976; 4,980,859; 5,012,132; 5,003,197; 5,023,694; 5,084,667; 5,153,880; 5,153,691;
5,161,137; 5,219,774; 5,270,927; 5,324,676; 5,434,396; 5,544,103; 5,587,573; 5,835,409; 5,977,585. Foreign patents and additional patents pending.
LIFE RELATED POLICY
In situations where semiconductor component failure may endanger life, system designers using this product should design the system with appropriate error detection
and correction, redundancy and back-up features to prevent such an occurrence.
Xicor's products are not authorized for use in critical components in life support devices or systems.
1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to
perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user.
2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or effectiveness.
Xicor, Inc. 2000 Patents Pending
REV 1.2 2/5/03
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Ordering Information
V
CC
Limits
Blank = 5V
10%
2.7 = 2.7V to 5.5V
Temperature Range
Blank = Commercial = 0
C to +70C
I = Industrial = 40
C to +85C
Package
M8 = 8-Lead MSOP
S8 = 8-Lead SOIC
End to End Resistance
W =
10K
X9116X
X
X
X
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