INTERSIL X93256_06

X93256
®
Data Sheet
March 24, 2006
Dual Digitally Controlled Potentiometers
(XDCPs™)
FEATURES
• Dual solid-state potentiometers
• Individual Up/Down interfaces
• 32 wiper tap points per potentiometer
—Wiper position stored in nonvolatile memory
and recalled on power-up
• 31 resistive elements per potentiometer
—Temperature compensated
—Maximum resistance tolerance of ± 25%
—Terminal voltage, 0 to VCC
• Low power CMOS
—VCC = 2.7 V - 5.5 V.
—Active current, 200µA typical per potentiometer
—Standby current, 4µA max per potentiometer
• High reliability
—Endurance 200,000 data changes per bit
—Register data retention, 100 years
• RTOTAL value = 12.5kΩ, 50kΩ
• Packages
—14 Ld TSSOP
• Pb-free plus anneal available (RoHS compliant)
FN8188.1
DESCRIPTION
The Intersil X93256 is a dual digitally controlled
potentiometer (XDCP). The device consists of two
resistor arrays, wiper switches, a control section, and
nonvolatile memory. The wiper positions are controlled
by individual Up/Down interfaces.
A potentiometer is implemented by a resistor array
composed of 31 resistive elements and a wiper switching
network. The position of each wiper element is controlled
by a set of independent CS, U/D, and INC inputs. The
position of the wiper can be stored in nonvolatile memory
and then be recalled upon a subsequent power-up
operation.
Each potentiometer is connected as a three-terminal
variable resistor and can be used in a wide variety of
applications including:
– Bias and Gain Control
– LCD Contrast Adjustment
BLOCK DIAGRAM
Detailed Single Potentiometer Description
General Description
U/D1
VCC (Supply Voltage)
RH1
30K
INC1
CS1
5-Bit
Up/Down
Counter
5-Bit
Nonvolatile
Memory
RL1
Control
and
Memory
Store and
Control
Recall
Circuitry
RH2
RW2
28
One
of
Thirty
Two
Decoder
RW
Transfer
Gates
Resistor
Array
2
1
VCC
RL2
30
29
RW1
Up/Down
(U/D1 & U/D2)
Increment
(INC1 & INC2)
Device Select
(CS1 & CS2)
RH1
31
0
VSS
RL1
VSS (Ground)
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
XDCP is a trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2005-2006. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
X93256
PIN CONFIGURATION
TSSOP
Rw1
1
14
RH1
RL1
2
13
U/D1
CS1
3
12
INC1
INC2
X93256 11
10
VCC
U/D2
4
5
RH2
6
9
CS2
RL2
VSS
7
8
Rw2
*NC can be left unconnected, or connected to any voltage between VSS and VCC.
Ordering Information
PART NUMBER
PART MARKING
RTOTAL (kΩ)
TEMPERATURE
RANGE (°C)
PACKAGE
PKG. DWG. #
X93256UV14I-2.7*
X93256UVG
50
-40 to 85
14 Ld TSSOP (4.4mm)
MDP0044
X93256UV14IZ-2.7*
(Note)
X93256UZG
50
-40 to 85
14 Ld TSSOP (4.4mm) (Pb-free)
MDP0044
X93256WV14I-2.7*
X93256WVG
12.5
-40 to 85
14 Ld TSSOP (4.4mm)
MDP0044
X93256WV14IZ-2.7*
(Note)
X93256WZG
12.5
-40 to 85
14 Ld TSSOP (4.4mm) (Pb-free)
MDP0044
*Add "T1" suffix for tape and reel.
NOTE: Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL
classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
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FN8188.1
March 24, 2006
X93256
PIN DESCRIPTIONS
TSSOP
Symbol
Brief Description
1
RW1
RW1. The RW1 pin of the X93256 is the wiper terminal of the first potentiometer which is equivalent to the
movable terminal of a mechanical potentiometer.
2
RL1
RL1. The RH1 and RL1 pins of the X93256 are equivalent to the fixed terminals of a
mechanical potentiometer. The minimum voltage is VSS and the maximum is VCC. The terminology of
RH1 and RL1 references the relative position of the terminal in relation to wiper movement
direction selected by the U/D input.
3
CS1
Chip Select 1 (CS1). The first potentiometer is selected when the CS1 input is LOW. The current counter
value is stored in nonvolatile memory when CS1 is returned HIGH while the INC1 input is also HIGH. After
the store operation is complete, the first potentiometer of the X93256 will be placed in the low power
standby mode until the first potentiometer is selected once again.
4
INC2
Increment 2 (INC2). The INC2 input is negative-edge triggered. Toggling INC2 will move the wiper of the
second potentiometer and either increment or decrement the counter in the direction indicated by the logic
level on the U/D2 input.
5
U/D2
Up/Down 2 (U/D2). The U/D2 input controls the direction of the second potentiometer wiper
movement and whether the counter for the second potentiometer is incremented or decremented.
6
RH2
RH2. The RH2 and RL2 pins of the X93256 are equivalent to the fixed terminals of a
mechanical potentiometer. The minimum voltage is VSS and the maximum is VCC. The terminology of
RH2 and RL2 references the relative position of the wiper terminal for the second potentiometer in relation
to the wiper movement direction selected by the U/D2 input.
7
VSS
Ground.
8
RW2
RW2. The RW2 pin of the X93256 is the wiper terminal of the second potentiometer which is
equivalent to the movable terminal of a mechanical potentiometer.
9
RL2
RL2. The RH2 and RL2 pins of the X93256 are equivalent to the fixed terminals of a
mechanical potentiometer. The minimum voltage is VSS and the maximum is VCC. The terminology of
RH2 and RL2 references the relative position of the wiper terminal for the second potentiometer in relation
to the wiper movement direction selected by the U/D2 input.
10
CS2
Chip Select 2 (CS2). The second potentiometer is selected when the CS2 input is LOW. The current
counter value is stored in nonvolatile memory when CS2 is returned HIGH while the INC2 input is also
HIGH. After the store operation is complete, the second potentiometer of the X93256 will be placed in the
low power standby mode until the second potentiometer is selected once again.
11
VCC
Supply Voltage.
12
INC1
Increment 1(INC1). The INC1 input is negative-edge triggered. Toggling INC1 will move the wiper of the
first potentiometer and either increment or decrement the counter in the direction indicated by the logic
level on the U/D1 input.
13
U/D1
Up/Down 1 (U/D1). The U/D1 input controls the direction of the first potentiometer wiper movement and
whether the counter for the first potentiometer is incremented or decremented.
14
RH1
RH1. The RH1 and RL1 pins of the X93256 are equivalent to the fixed terminals of a
mechanical potentiometer. The minimum voltage is VSS and the maximum is VCC. The terminology of
RH1 and RL1 references the relative position of the wiper terminal for the first potentiometer in relation to
the wiper movement direction selected by the U/D1 input.
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FN8188.1
March 24, 2006
X93256
ABSOLUTE MAXIMUM RATINGS
COMMENT
Temperature under bias .................... -65°C to +135°C
Storage temperature ......................... -65°C to +150°C
Voltage on CS, INC, U/D, RH, RL and VCC
with respect to VSS .............................. -1V to +6.5V
Lead temperature (soldering 10 seconds) ......... 300°C
Maximum reflow temperature (40 seconds) ...... 240°C
Maximum resistor current ..................................... 2mA
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
specification) is not implied. Exposure to absolute
maximum rating conditions for extended periods may
affect device reliability.
RECOMMENDED OPERATING CONDITIONS
Temperature
Industrial
Min.
Max.
-40°C
+85°C
Supply Voltage (VCC)
X93256
Limits
2.7V ± 5.5%(7)
POTENTIOMETER CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.)
Limits
Symbol
RTOT
VR
Parameter
End to end resistance
RH, RL terminal voltages
Min.
Typ.
Max.
Unit
9.375
12.5
15.625
kΩ
W option (5)
37.5
50
62.5
kΩ
U option (5)
VCC
V
1
mW(7)
RTOTAL = 50kΩ (5) (6)
dBV(7)
Ref: 1kHz (5) (6)
0
Power rating
Noise
-120
RW
Wiper Resistance
IW
Wiper Current
Resolution
RTOTAL temperature coefficient
CH/CL/CW
Potentiometer capacitances
±35
10/10/25
(5)
1100
Ω
(5) (6)
0.6
mA
(5) (6)
3
Absolute linearity(1)
Relative linearity(2)
Test Conditions/Notes
%
(5)
±1
MI(3)
VH(n)(actual) - VH(n)(expected) (5)
±0.5
MI(3)
VH(n+1) - [VH(n) + MI] (5)
ppm/°C (5) (6)
pF(6)
See circuit #2 (5)
Notes: (1) Absolute linearity is utilized to determine actual wiper voltage versus expected voltage = (VH(n)(actual) - VH(n)(expected)) =
±1 Ml Maximum. n = 1 .. 29 only.
(2) Relative linearity is a measure of the error in step size between taps = VH(n+1) - [VH(n) + Ml] = ±0.5 Ml, n = 1 .. 29 only.
(3) 1 Ml = Minimum Increment = RTOT/31.
(4) Typical values are for TA = 25°C and nominal supply voltage.
(5) This parameter only applies to a single potentiometer.
(6) Typical parameter is guaranteed by characterization.
(7) When performing multiple write operations, VCC must not decrease by more than 150mV from it’s initial value.
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FN8188.1
March 24, 2006
X93256
D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified.)
Limits
Symbol
ICC1
ICC2
ISB
Parameter
Min.
VCC active current (Increment)
Typ.(4)
Max.
Unit
Test Conditions
50
250
µA
CS = VIL, U/D = VIL or VIH and INC
= 0.4V @ max. tCYC VCC = 3V
200
300
VCC active current (Store)
(EEPROM Store)
Standby supply current
CS = VIL, U/D = VIL or VIH and INC
= 0.4V @ max. tCYC VCC = 5V
600
µA
CS = VIH, U/D = VIL or VIH and INC
= VIH @ max. tWR VCC = 3V
1400
µA
CS = VIH, U/D = VIL or VIH and INC
= VIH @ max. tWR VCC = 5V
1
µA
CS = VCC - 0.3V, U/D and INC =
VSS or VCC - 0.3V VCC = 3V
4
µA
CS = VCC - 0.3V, U/D and INC =
VSS or VCC - 0.3V VCC = 5V
±1
µA
VIN = VCC (5)
ILI
CS input leakage current
ILI
CS input leakage current
60
100
150
µA
VCC = 3V, CS = 0 (5)
ILI
CS input leakage current
120
200
250
µA
VCC = 5V, CS = 0 (5)
ILI
INC, U/D input leakage current
±1
µA
VIN = VSS to VCC (5)
VIH
CS, INC, U/D input HIGH voltage
VCC x 0.7
VCC + 0.5
V
(5)
VIL
CS, INC, U/D input LOW voltage
-0.5
VCC x 0.1
V
(5)
10
pF
VCC = 3V, VIN = VSS, TA = 25°C,
f = 1MHz (6)
CIN
(5)(7)
CS, INC, U/D input capacitance
ENDURANCE AND DATA RETENTION
Parameter
Min.
Unit
Minimum endurance
200,000
Data changes per bit
Data retention
100
Years
Test Circuit #1
Circuit #2 SPICE Macro Model
Test Point
VH/RH
RTOTAL
RH
CH
CW
CL
RL
10pF
25pF
10pF
A.C. CONDITIONS OF TEST
Input pulse levels
0V to 3V
Input rise and fall times
10ns
Input reference levels
1.5V
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FN8188.1
March 24, 2006
X93256
A.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified)
Limits
Symbol
Parameter
Typ.(6)
Min.
Unit
Max.
tCl
CS to INC setup
100
ns
tlD
INC HIGH to U/D change
100
ns
tDI
U/D to INC setup
100
ns
tlL
INC LOW period
1
µs
tlH
INC HIGH period
1
µs
tlC
INC Inactive to CS inactive
1
µs
tCPH
CS Deselect time (NO STORE)
250
ns
tCPH
CS Deselect time (STORE)
10
ms
tCYC
INC cycle time
2
µs
tR, tF(6)
tR VCC(6)
tWR
INC input rise and fall time
0.2
VCC power-up rate
Store cycle
5
500
µs
10,000
V/ms
10
ms
POWER UP AND DOWN REQUIREMENTS
There are no restrictions on the power-up or power-down conditions of VCC and the voltages applied to the potentiometer
pins provided that VCC is always more positive than or equal to VH and VL, i.e., VCC ≥ VH,VL. The VCC ramp rate spec is
always in effect.
A.C. TIMING
CS
tCYC
tCI
tIL
tIH
tIC
(Store)
tCPH
90%
90%
10%
INC
tID
tDI
tF
tR
U/D
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FN8188.1
March 24, 2006
X93256
PIN DESCRIPTIONS
(In the text, CS, INC, U/D, RH, RW , and RL are used to
refer to either CS1 or CS2, etc. Note: These signals can
be applied independently or at the same time.)
RH and RL
The RH and RL pins of the X93256 are equivalent to the
fixed terminals of a mechanical potentiometer. The
minimum voltage is VSS and the maximum is VCC. The
terminology of RH and RL references the relative position
of the terminal in relation to wiper movement direction
selected by the U/D input per potentiometer.
RW
The RW pin of the X93256 is the wiper terminal of the
potentiometer which is equivalent to the movable terminal of
a mechanical potentiometer
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.
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 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. Each resistor array
is comprised of 31 individual resistors connected in
series. At either end of the array and between each
resistor is an electronic switch that transfers the
connection at that point to the wiper.
Each 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.
Increment (INC)
If the wiper is moved several positions, multiple taps are
connected to the wiper for tIW (INC to VW change). The
2-terminal resistance value for the device can temporarily
change by a significant amount if the wiper is moved
several positions.
The INC input is negative-edge triggered. Toggling INC
will move the wiper and either increment or decrement
the pertatining potentiometer’s counter in the direction
indicated by the logic level on the pertaining
potentiometer’s U/D input.
When the device is powered-down, the last wiper
position stored will be maintained in the nonvolatile
memory for each potentiometer. When power is
restored, the contents of the memory are recalled and
each wiper is set to the value last stored.
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.
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FN8188.1
March 24, 2006
X93256
INSTRUCTIONS AND PROGRAMMING
The INC, U/D and CS inputs control the movement of the
pertaining wiper along the resistor array. With CS set
LOW the pertaining potentiometer 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 five bit
counter. The output of this counter is decoded to select
one of thirty two wiper positions along the resistive array.
The value of the counter is stored in nonvolatile memory
whenever each CS transitions HIGH while the pertaining
INC input is also HIGH. In order to avoid an accidental
store during power-up, each CS must go HIGH with VCC
during initial power-up. When left open, each CS pin is
internally pulled up to VCC by an internal 30K resistor.
The system may select the X93256, move any wiper and
deselect the device without having to store the latest
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 system or until a
power-up/down cycle recalled the previously stored data.
In order to recall the stored position of the wiper on
power-up, the CS pin must be held HIGH.
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 preference, system
parameter changes due to temperature drift, or other
system trim requirements.
8
The state of U/D may be changed while CS remains
LOW. This allows the host system to enable the device
and then move each wiper up and down until the proper
trim is attained.
MODE SELECTION
CS
INC
U/D
Mode
L
H
Wiper Up
L
L
Wiper Down
H
X
Store Wiper Position
X
X
Standby Current
L
X
No Store, Return to Standby
L
H
Wiper Up (not recommended)
L
L
Wiper Down (not recommended)
H
SYMBOL TABLE
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
FN8188.1
March 24, 2006
X93256
Packaging Information
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
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FN8188.1
March 24, 2006