Datasheet X9315WS-2,7, X9315WS, X9315WPI-2,7, X9315WPI, X9315WP-2,7 Datasheet (XICOR)

6732-2.0 5/30/97 T1/C0/D0 SH

1

Characteristics subject to change without notice

APPLICATION NOTE

A V A I L A B L E

Low Noise, Low Power, 32 Taps

X9315

E

2

POT

TM

Nonvolatile Digital Potentiometer

FEATURES

• Low Power CMOS
—V

CC

= 2.7V to 5.5V, Single Supply
—Active Current, 50 µ A (Increment) max
—Active Current, 400 µ A (Store) Max
—Standby Current, 1 µ A Max

• Low Noise

• 31 Resistive Elements
—Temperature Compensated
— ± 20% End to End Resistance Range
—V

SS

to V

CC

Range

• 32 Wiper T ap Points
—Wiper Positioned via Three-Wire Interface
—Similar to TTL Up/Down Counter
—Wiper Position Stored in Nonvolatile Memory

and Recalled on Power-Up

• 100 Year Wiper Position Data Retention

• X9315Z = 1K Ω

• X9315W = 10K Ω

• Packages
—8-Lead SOIC
—8-Lead MSOP
—8-Pin DIP

DESCRIPTION

The Xicor X9315 is a solid state "micropower" nonvol­atile potentiometer and is ideal for digitally controlled
resistance trimming.

The X9315 is a resistor array composed of 31 resistive
elements. Between each element and at either end are
tap points accessible to the wiper element. The posi­tion of the wiper element is controlled by the 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.

The resolution of the X9315 is equal to the maximum
resistance value divided by 31. As an example, for the
X9315W (10K Ω ) each tap point represents 323 Ω .

All Xicor nonvolatile digital potentiometers are de­signed and tested for applications requiring extended
endurance and data retention.

FUNCTIONAL DIAGRAM

5-BIT

UP/DOWN

COUNTER

5-BIT

NONVOLATILE

MEMORY

STORE AND

RECALL

CONTR OL

CIRCUITR Y

ONE

OF

THIRTY-

TWO

WIPER

POSITION

DECODER

RESIST OR

ARRA Y

VL
VW

VH

U/D
INC

CS

CMOS SWITCH

6732 FM1

E

2

POT™ is a trademark of Xicor, Inc.

AN104

X9315

2

PIN DESCRIPTIONS
V

H

and V

L

The high (V

H

) and low (V

L

) terminals of the X9315 are
equivalent to the fixed terminals of a mechanical potenti­ometer. The minimum v oltage is V

SS

and the maximum is

V

CC

. It should be noted that the terminology of V

L

and V

H

references the relative position of the terminal in relation
to wiper movement direction selected by the U/D

input

and not the voltage potential on the terminal.

V

W

V

w

is the wiper terminal, 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 ter minal series resistance is typically
400 Ω .

Up/Down (U/D

)

The U/D input controls the direction of the wiper move­ment and whether the counter is incremented or decre­mented.

Increment (INC)

The INC input is negative-edge triggered. Toggling INC
will move the wiper and either increment or decrement
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 retur ned HIGH while the INC input is also
HIGH. After the store operation is complete the X9315
will be placed in the low power standby mode until the
device is selected once again.

PIN CONFIGURATION

6732 FM2

PIN NAMES

6732 FM T01

Symbol Description

V

H

High Terminal

V

W

Wiper Terminal

V

L

Low Terminal

V

SS

Ground

V

CC

Supply Voltage

U/D

Up/Down Input

INC

Increment Input

CS

Chip Select Input

V

CC

CS
V

L

V

W

INC
U/D

V

H

V

SS

1
2
3
4

8
7
6
5

X9315

DIP/SOIC/MSOP

X9315

3

DEVICE OPERATION

There are three sections of the X9315: the input control,
counter and decode section; the nonvolatile memory;
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 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 potential at that point to the wiper .

The INC

, U/D and CS inputs control the movement of the
wiper along the resistor array. With CS set LOW the
X9315 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 seven bit counter. The output of this counter
is decoded to select one of thirty two wiper positions
along the resistive array.

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 e xtreme.

The value of the counter is stored in nonvolatile memory
whenever CS transistions HIGH while the INC input is
also HIGH.

When the X9315 is powered-down, the last counter posi­tion stored will be maintained in the nonvolatile memory.
When power is restored, the contents of the memory are
recalled and the counter is reset to the value last stored.

Operation Notes

The system may select the X9315, move the wiper and
deselect the device without having to store the latest
wiper position in nonvolatile memory. The wiper move­ment is performed as described above; once the new
position is reached, the system would the keep INC

LOW
while taking CS HIGH. The new wiper position would be
maintained until changed by the system or until a power­up/down cycle recalled the previously stored data.

This would allow the system to alwa ys 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, etc...

The state of U/D

may be changed while CS remains
LOW. This allows the host system to enable the X9315
and then move the wiper up and down until the proper
trim is attained.

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

6732 FM 3

X9315

4

ABSOLUTE MAXIMUM RATINGS*

Temperature under Bias.........................–65 ° C to +135 ° C

Storage Temperature..............................–65 ° C to +150 ° C

V oltage on CS

, INC, U/D V

H

, V

L

and V

CC

with Respect to V

SS

..................................–1V to +7V

∆

V = |V

H

–V

L

| .................................................................5V

Lead Temperature (Soldering 10 seconds).............300 ° C

Wiper Current ........................................................... ± 1mA

*COMMENT

Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only and 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.

ANALOG CHARACTERISTICS
Electrical Characteristics

Temperature under Bias.........................–65 ° C to +135 ° C

End-to-End Resistance Tolerance .......................... ± 20%

Pow er Rating at 25 ° C..............................................10mW

Wiper Current ................................................. ± 1mA Max.

Typical Wiper Resistance ............................400 Ω at 1mA

Typical Noise.................................. < –140dB √ Hz Ref: 1V

Resolution

Resistance ................................................................... 3%

Linearity

Absolute Linearity

(1)

........................................... ± 1.0 Ml

(2)

Relative Linearity

(3)

........................................... ± 0.2 Ml

(2)

Temperature Coefficient

(–40 ° C to +85 ° C) ..............................+300 ppm/ ° C Typical

Ratiometric Temperature Coefficient .................. ± 20 ppm

Wiper Adjustability

Unlimited Wiper Adjustment (Non-Store oper ation)

Wiper Position Store Operations..........................100,000

Physical Characteristics

Marking Includes

Manufacturer’s Trademark
Resistance Value or Code
Date Code

Test Circuit #2

6732 FM 5

FORCE
CURRENT

V

L

VW

V

H

TEST POINT

Test Circuit #1

6732 FM 4

TEST POINT

V

W

V

H

V

L

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) 1 Ml = Minimum Increment = R

TOT

/31.

(3) Relative Linearity is a measure of the error in step size between taps = V

W(n+1)

– [V

w(n)

+ Ml] = +0.2 Ml.

X9315

5

RECOMMENDED OPERATING CONDITIONS

6732 PGM T02 6732 PGM T03

Temperature Min. Max.

Commercial 0 ° C +70 ° C

Industrial –40

°

C +85 ° C

Supply Voltage Limits

X9315 5V ± 10%

X9315-2.7 2.7V to 5.5V

D.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified.)

6732 PGM T04

STANDARD PARTS

6732 PGM T05

Notes: (4) Typical values are f or T

A

= 25°C and nominal supply voltage.

(5) This parameter is periodically sampled and not 100% tested.

Symbol Parameter

Limits

Units Test ConditionsMin. Typ.

(4)

Max.

I

CC1

VCC Active Current
(Increment)

50 µA CS = VIL, U/D = VIL or VIH and

INC

= 0.4V/2.4V @ max. t

CYC

I

CC2

VCC Active Current
(Store)

400 µA CS = VIH, U/D = VIL or VIH

and INC

= V

IH

I

SB

Standby Supply Current 1 µA CS = VCC – 0.3V, U/D and

INC

= VSS or VCC – 0.3V

I

LI

CS, INC, U/D Input ±10 µA

VIN = V

SS

to V

CC

Leakage Current

V

IH

CS, INC, U/D Input 2

VCC + 1

V

HIGH Voltage

V

IL

CS, INC, U/D Input –0.5 0.8 V
LOW Voltage

R

W

Wiper Resistence 400 1000 Ω Max. Wiper Current ±1mA

V

VH

VH Terminal Voltage

V

SS

V

CC

V

V

VL

VL Terminal Voltage

V

SS

V

CC

V

C

IN

(5)

CS, INC, U/D Input 10 pF

VCC = 5V, VIN = VSS,

Capacitance

T

A

= 25°C, f = 1MHz

Part Number Maximum Resistance Wiper Increments Minimum Resistance

X9315Z 1KΩ 32.3Ω 100Ω

X9315W 10KΩ 323Ω 100Ω

X9315

6

A.C. CONDITIONS OF TEST

6732 PGM T06

MODE SELECTION

6732 PGM T07

Input Pulse Levels 0V to 3V
Input Rise and Fall Times 10ns
Input Reference Levels 1.5V

CS INC U/D Mode

L H Wiper Up
L L Wiper Down

H X Store Wiper Position

H X X Standby

L X No Store, Return to Standby

A.C. OPERATING CHARACTERISTICS (Over recommended operating conditions unless otherwise specified)

6732 PGM T08

A.C. TIMING

Notes: (6) Typical values are for TA = 25°C and nominal supply voltage.

(7) This parameter is periodically sampled and not 100% tested.
(8) MI in the A.C. timing diagram refers to the minimum incremental change in the VW output due to a change in the wiper position.

Limits

Symbol Parameter Min. Typ.

(6)

Max. Units

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 µs

t

lL

INC LOW Period 1 µs

t

lH

INC HIGH Period 1 µs

t

lC

INC Inactive to CS Inactive 1 µs

t

CPH

CS Deselect Time (NO STORE) 100 ns

t

IW

INC to Vw Change 1 5 µs

t

CYC

INC Cycle Time 4 µs

t

R

,

t

F

(7)

INC Input Rise and Fall Time 500 µs

t

PU

(7)

Power up to Wiper Stable 5 µs

t

R VCC

(7)

VCC Power-up Rate 0.2 50 mV/µs

t

WR

Store Cycle 5 10 ms

6732 FM 06

CS

INC

U/D

VW

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%

X9315

7

TYPICAL NOISE

TYPICAL RTOTAL vs. TEMPERATURE

0

-10

-20

-30

-40

-50

-60

-70

-80

-90

-100

-110

-120

-130

-140

-150
0 10 20 30 40 50 60 70 80 90 100

Frequenc y (KHz)

Noise (dB)

110 120 130 140 150 160 170 180 190 200

10000

9800

9600

9400

9200

9000

8800

8600

8400

8200

8000

Rtotal

-55

-45

-35 -25 -15 -5 5

15 25

35 45

55 65 75

Temperature

85 95 105 115 125

C°

X9315

8

TYPICAL TOTAL RESISTANCE TEMPERATURE COEFFICIENT

TYPICAL WIPER RESISTANCE

-55

-350

-300

-250

-200

-150

-100

-50

0

-45 -35 -25 -15 -5 5 15 25 35
Temperature

PPM

45 55 65 75 85 95 105 115 125 °C

0

0

100

200

300

400

Rw (Ohms)

500

600

700

800

2 4 6 8 10 12 14 16

Tap

18 20 22 24 26 28 30 32

X9315

9

TYPICAL ABSOLUTE % ERROR PER TAP POSITION

TYPICAL RELATIVE % ERROR PER TAP POSITION

40.0%

30.0%

20.0%

10.0%

0.0%

-10.0%

-20.0%

-30.0%

-40.0%
0 3 6 9 12 15

Tap

Absolute % Error

18 21 24 27 30

20.0%

15.0%

10.0%

5.0%

0.0%

-5.0%

-10.0%

-15.0%

-20.0%
0 3 6 9 12 15

Tap

Relative % Error

18 21 24 27 30

X9315

10

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)
REF.

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)

3003 ILL 01

X9315

11

PACKAGING INFORMATION

NOTE:

1. ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)

2. PACKAGE DIMENSIONS EXCLUDE MOLDING FLASH

0.020 (0.51)

0.016 (0.41)

0.150 (3.81)

0.125 (3.18)

0.110 (2.79)

0.090 (2.29)

0.430 (10.92)

0.360 (9.14)

0.300

(7.62) REF.

PIN 1 INDEX

0.145 (3.68)

0.128 (3.25)

0.025 (0.64)

0.015 (0.38)

PIN 1

SEATING

PLANE

0.065 (1.65)

0.045 (1.14)

0.260 (6.60)

0.240 (6.10)

0.060 (1.52)

0.020 (0.51)

TYP.0.010 (0.25)

0°

15°

8-LEAD PLASTIC DUAL IN-LINE PACKAGETYPE P

HALF SHOULDER WIDTH ON

ALL END PINS OPTIONAL

0.015 (0.38)
MAX.

0.325 (8.25)

0.300 (7.62)

X9315

12

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 PLACESFOOTPRINT

X9315

13

ORDERING INFORMATION

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. mak es 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,
licenses are implied.

U.S. PATENTS

Xicor products are covered by one or more of the following U.S. Patents: 4,263,664; 4,274,012; 4,300,212; 4,314,265; 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. Foreign patents and additional patents pending.

LIFE RELA TED 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 prev ent such an occurence.

Xicor’s products are not authorized for use in critical components in lif e 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 saf ety or eff ectiv eness .

VCC Limits

Blank = 5V ±10%
–2.7 = 2.7V to 5.5V

Temperature Range

Blank = Commercial = 0°C to +70°C
I = Industrial = –40°C to +85°C

Package

M = 8-Lead MSOP
P = 8-Lead Plastic DIP
S = 8-Lead SOIC

End to End Resistance

Z = 1KΩ
W = 10KΩ

X9315X X X X