X9221AWSIT1 - Xicor, Inc. - Datasheet.Cloud

REV 1.1.3 8/21/02

Characteristics subject to change without notice.

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X9221A

Dual Digitally Controlled Potentiometer (XDCP

™

)

FEATURES

• Two XDCPs in one package

• 2-wire serial interface

• Register oriented format, 8 registers total

—Directly write wiper position

—Read wiper position

—Store as many as four positions per pot

• Instruction format

—Quick transfer of register contents to resistor

array

• Direct write cell

—Endurance–100,000 writes per bit per register

• Resistor array values

—2K

Ω

, 10K

Ω

, 50K

Ω

• Resolution: 64 taps each pot

• 20-lead plastic DIP and 20-lead SOIC packages

DESCRIPTION

The X9221A integrates two digitally controlled potenti-

ometers (XDCP) on a monolithic CMOS integrated

microcircuit.

The digitally controlled potentiometer is implemented

using 63 resistive elements in a series array. Between

each element are tap points connected to the wiper

terminal through switches. The position of the wiper on

the array is controlled by the user through the 2-wire

bus interface. Each potentiometer has associated with

it a volatile Wiper Counter Register (WCR) and 2 non-

volatile Data Registers (DR0:DR1) that can be directly

written to and read by the user. The contents of the

WCR controls the position of the wiper on the resistor

array through the switches. Power up recalls the con-

tents of DR0 to the WCR.

The XDCP can be used as a three-terminal potentiom-

eter or as a two-terminal variable resistor in a wide

variety of applications including control, parameter

adjustments, and signal processing.

64 Taps, 2-Wire Serial Bus

BLOCK DIAGRAM

VH0/RH0

VL0/RL0

VW0/RW0

Wiper

Counter

(WCR)

Array

Pot 1

Wiper

Counter

(WCR)

Data

SCL

SDA

Interface

and

Control

Circuitry

VCC

VSS

Pot 0

VH1/RH1

VL1/RL1

VW1/RW1

PPLICATION

OTE

A V A I L A B L E

AN20 • AN42–53 • AN71 • AN73 • AN88 • AN91–92 • AN99 • AN115 • AN120 • AN124 • AN133 • AN134

X9221A

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PIN DESCRIPTIONS

Host Interface Pins

Serial Clock (SCL)

The SCL input is used to clock data into and out of the

X9221A.

Serial Data (SDA)

SDA is a bidirectional pin used to transfer data into

and out of the device. It is an open drain output and

may be wire-ORed with any number of open drain or

open collector outputs. An open drain output requires

the use of a pull-up resistor. For selecting typical val-

ues, refer to the guidelines for calculating typical val-

ues on the bus pull-up resistors graph.

Address

The Address inputs are used to set the least signiﬁ-

cant 4 bits of the 8-bit slave address. A match in the

slave address serial data stream must be made with

the Address input in order to initiate communication

with the X9221A

Potentiometer Pins

–V

), V

–V

)

The V

and V

inputs are equivalent to the ter-

minal connections on either end of a mechanical

potentiometer.

–V

)

The wiper outputs are equivalent to the wiper output of

a mechanical potentiometer.

PIN CONFIGURATION

PIN NAMES

PRINCIPLES OF OPERATION

The X9221A is a highly integrated microcircuit incor-

porating two resistor arrays, their associated registers

and counters and the serial interface logic providing

direct communication between the host and the XDCP

potentiometers.

Serial Interface

The X9221A supports a bidirectional bus oriented pro-

tocol. The protocol deﬁnes any device that sends data

onto the bus as a transmitter and the receiving device

as the receiver. The device controlling the transfer is a

master and the device being controlled is the slave.

The master will always initiate data transfers and pro-

vide the clock for both transmit and receive operations.

Therefore, the X9221A will be considered a slave

device in all applications.

Clock and Data Conventions

Data states on the SDA line can change only during

SCL LOW periods (t

LOW

). SDA state changes during

SCL HIGH are reserved for indicating start and stop

conditions.

Start Condition

All commands to the X9221A are preceded by the

start condition, which is a HIGH to LOW transition of

SDA while SCL is HIGH (t

HIGH

). The X9221A continu-

ously monitors the SDA and SCL lines for the start

condition, and will not respond to any command until

this condition is met.

Stop Condition

All communications must be terminated by a stop con-

dition, which is a LOW to HIGH transition of SDA while

SCL is HIGH.

VW0/RW0

VL0/RL0

VH0/RL0

VW1/RW1

VL1/RL1

VH1/RH1

SDA

VSS

VCC

RES

SCL

RES

DIP/SOIC

X9221A

Symbol Description

SCL Serial Clock

SDA Serial Data

A0–A3 Address

–V

Potentiometers

(terminal equivalent)

–V

Potentiometers

(wiper equivalent)

RES Reserved (Do not connect)

X9221A

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Acknowledge

Acknowledge is a software convention used to provide

a positive handshake between the master and slave

devices on the bus to indicate the successful receipt of

data. The transmitting device, either the master or the

slave, will release the SDA bus after transmitting eight

bits. The master generates a ninth clock cycle and dur-

ing this period the receiver pulls the SDA line LOW to

acknowledge that it successfully received the eight bits

of data. See Figure 7.

The X9221A will respond with an acknowledge after

recognition of a start condition and its slave address

and once again after successful receipt of the com-

mand byte. If the command is followed by a data byte

the X9221A will respond with a ﬁnal acknowledge.

Array Description

The X9221A is comprised of two resistor arrays. Each

array contains 63 discrete resistive segments that are

connected in series. The physical ends of each array

are equivalent to the ﬁxed terminals of a mechanical

potentiometer (V

and V

inputs).

At both ends of each array and between each resistor

segment is a FET switch connected to the wiper (V

) output. Within each individual array only one

switch may be turned on at a time. These switches are

controlled by the Wiper Counter Register (WCR). The

six least signiﬁcant bits of the WCR are decoded to

select, and enable, one of sixty-four switches.

The WCR may be written directly, or it can be changed

by transferring the contents of one of four associated

data registers into the WCR. These data registers and

the WCR can be read and written by the host system.

Device Addressing

Following a start condition the master must output the

address of the slave it is accessing. The most signiﬁ-

cant four bits of the slave address are the device type

identiﬁer (refer to Figure 1 below). For the X9221A this

is ﬁxed as 0101[B].

Figure 1. Slave Address

The next four bits of the slave address are the device

address. The physical device address is deﬁned by the

state of the A0-A3 inputs. The X9221A compares the

serial data stream with the address input state; a suc-

cessful compare of all four address bits is required for

the X9221A to respond with an acknowledge.

Acknowledge Polling

The disabling of the inputs, during the internal nonvola-

tile write operation, can be used to take advantage of

the typical 5ms EEPROM write cycle time. Once the

stop condition is issued to indicate the end of the non-

volatile write command the X9221A initiates the inter-

nal write cycle. ACK polling can be initiated

immediately. This involves issuing the start condition

followed by the device slave address. If the X9221A is

still busy with the write operation no ACK will be

returned. If the X9221A has completed the write opera-

tion an ACK will be returned and the master can then

proceed with the next operation.

Flow 1. ACK Polling Sequence

10 0 A3 A2 A1 A0

Device Type

Identifier

Device Address

Nonvolatile Write

Command Completed

Enter ACK Polling

Issue

START

Issue Slave

Address

ACK

Returned?

Further

Operation?

Issue

Instruction

Proceed

Issue STOP

YES

Proceed

Issue STOP

X9221A

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Instruction Structure

The next byte sent to the X9221A contains the instruc-

tion and register pointer information. The four most

signiﬁcant bits are the instruction. The next four bits

point to one of two pots and when applicable they

point to one of four associated registers. The format is

shown below in Figure 2.

Figure 2. Instruction Byte Format

The four high order bits deﬁne the instruction. The

sixth bit (P0) selects which one of the two potentiome-

ters is to be affected by the instruction. The last two

bits (R1 and R0) select one of the four registers that is

to be acted upon when a register oriented instruction

is issued.

Four of the nine instructions end with the transmission

of the instruction byte. The basic sequence is illus-

trated in Figure 3. These two-byte instructions

exchange data between the WCR and one of the data

registers. A transfer from a data register to a WCR is

essentially a write to a static RAM. The response of

the wiper to this action will be delayed t

STPWV

. A trans-

fer from WCR’s current wiper position to a data regis-

ter is a write to nonvolatile memory and takes a

minimum of t

to complete. The transfer can occur

between either potentiometer and their associated

registers or it may occur between both of the potenti-

ometers and one of their associated registers.

Four instructions require a three-byte sequence to

complete. These instructions transfer data between

the host and the X9221A; either between the host and

one of the data registers or directly between the host

and the WCR. These instructions are: Read WCR,

read the current wiper position of the selected pot;

Write WCR, change current wiper position of the

selected pot; Read Data Register, read the contents of

the selected nonvolatile register; Write Data Register,

write a new value to the selected data register. The

sequence of operations is shown in Figure 4.

The Increment/Decrement command is different from

the other commands. Once the command is issued

and the X9221A has responded with an acknowledge,

the master can clock the selected wiper up and/or

down in one segment steps; thereby, providing a ﬁne

tuning capability to the host. For each SCL clock pulse

HIGH

) while SDA is HIGH, the selected wiper will

move one resistor segment towards the V

termi-

nal. Similarly, for each SCL clock pulse while SDA is

LOW, the selected wiper will move one resistor seg-

ment towards the V

terminal. A detailed illustration

of the sequence and timing for this operation are

shown in Figures 5 and 6 respectively.

I1I2I3 I0 0 P0 R1 R0

Potentiometer

Select

Instructions

Figure 3. Two-Byte Command Sequence

0101A3A2A1A0

AI3 I2 I1 I0 0 P0 R1 R0

SCL

SDA

X9221A

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Figure 4. Three-Byte Command Sequence

Figure 5. Increment/Decrement Command Sequined

Figure 6. Increment/Decrement Timing Limits

0 1 0 1 A3 A2 A1 A0 AI3 I2 I1 I0 0 P0 R1 R0

SCL

SDA

0 0 D5 D4 D3 D2 D1 D0

0 1 0 1 A3 A2 A1 A0 I3 I2 I1 I0 0 P0 R1 R0

SCL

SDA

SCL

SDA

VW/RW

INC/DEC

CMD

Issued

Voltage Out

tCLWV

X9221A

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Table 1. Instruction Set

Note: (7) N/A = Not applicable or don’t care; that is, a data register is not involved in the operation and need not be addressed (typical)

Figure 7. Acknowledge Response from Receiver

Instruction

Instruction Format

OperationI3I2I1I00P

0R1R0

Read WCR 1001 0 1/0N/A

(7) N/A Read the contents of the Wiper Counter Register

pointed to by P0

Write WCR 1010 0 1/0N/AN/AWrite new value to the Wiper Counter Register

pointed to by P0

Read Data Register 1011 0 1/01/01/0Read the contents of the Register pointed to by

P0 and R1–R0

Write Data Register 1100 0 1/01/01/0Write new value to the Register pointed to by

P0 and R1–R0

XFR Data Register

to WCR

1101 0 1/01/01/0Transfer the contents of the Register pointed to

by P0 and R1–R0 to its associated WCR

XFR WCR to Data

1110 0 1/01/01/0Transfer the contents of the WCR pointed to by

P0 to the Register pointed to by R1–R0

Global XFR Data

0001N/AN/A1/01/0Transfer the contents of the Data Registers

pointed to by R1–R0 of both pots to their

respective WCR

Global XFR WCR

to Data Register

1000N/AN/A1/01/0Transfer the contents of all WCRs to their

respective data Registers pointed to by R1–R0

of both pots

Increment/

Decrement Wiper

0010 0 1/0N/AN/AEnable Increment/decrement of the WCR

pointed to by P0

SCL from

Data Output

189

START Acknowledge

Master

from Transmitter

Data Output

from Receiver

X9221A

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DETAILED OPERATION

Both XDCP potentiometers share the serial interface

and share a common architecture. Each potentiometer

is comprised of a resistor array, a wiper counter regis-

ter and four data registers. A detailed discussion of the

Wiper Counter Register

The X9221A contains two wiper counter registers

(WCR), one for each XDCP potentiometer. The WCR

can be envisioned as a 6-bit parallel and serial load

counter with its outputs decoded to select one of sixty-

four switches along its resistor array. The contents of

the WCR can be altered in four ways: it may be written

directly by the host via the Write WCR instruction

(serial load); it may be written indirectly by transferring

the contents of one of four associated data registers

via the XFR Data Register instruction (parallel load); it

can be modiﬁed one step at a time by the Increment/

Decrement instruction; ﬁnally, it is loaded with the con-

tents of its data register zero (R0) upon power-up.

The WCR is a volatile register; that is, its contents are

lost when the X9221A is powered-down. Although the

upon power-up, it should be noted this may be different

from the value present at power-down.

Data Registers

Each potentiometer has four nonvolatile data registers.

These can be read or written directly by the host and

data can be transferred between any of the four data

registers and the WCR. It should be noted all opera-

tions changing data in one of these registers is a non-

volatile operation and will take a maximum of 10ms.

If the application does not require storage of multiple

settings for the potentiometer, these registers can be

used as regular memory locations that could possibly

store system parameters or user preference data.

Figure 8. Detailed Potentiometer Block Diagram

Serial Data Path

From Interface

Circuitry

Serial

Bus

Input

Parallel

Bus

Input

Wiper

Counter

INC/DEC

Logic

UP/DN

CLK

Modified SCL

UP/DN

VH/RH

If WCR = 00[H] then VW/RW = VL/RL

If WCR = 3F[H] then VW/RW = VH/RH

8 6 C

VL/RL

VW/RW

X9221A

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ABSOLUTE MAXIMUM RATINGS

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

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

Voltage on SCK, SCL or any address

input with respect to VSS.........................–1V to +7V

Voltage on any VH/RH, VW/RW or VL/RL

referenced to VSS................................... +6V / –4.3V

∆V = |VH/RH–VL/RL|........................................... 10.3V

Lead temperature (soldering, 10 seconds).........300°C

IW (10 seconds) ................................................. ±6mA

COMMENT

Stresses above those listed under “Absolute Maximum

Ratings” may cause permanent damage to the device.

This is a stress rating only; functional operation of the

device (at these or any other conditions above those

indicated in the operational sections of this speciﬁca-

tion) is not implied. Exposure to absolute maximum

rating conditions for extended periods may affect

device reliability.

RECOMMENDED OPERATING CONDITIONS

Temperature Min. Max.

Commercial 0°C +70°C

Industrial –40°C +85°C

Supply Voltage Limits

X9221A 5V ±10%

ANALOG CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.)

Symbol Parameter

Limits

Test ConditionsMin. Typ. Max. Unit

RTOTAL End to End Resistance –20 +20 %

Power Rating 50 mW 25°C, each pot

IW Wiper Current –3 +3 mA

RWWiper Resistance 40 130 ΩWiper Current = ± 1mA

VTERM Voltage on any VH/RH, VW/RW or

VL/RL Pin

–3.0 +5 V

Noise ≤120 dBV Ref: 1V

Resolution 1.6 % See Note 5

Absolute Linearity(1) –1 +1 MI(3) Vw(n)(actual)–Vw(n)(expected)

Relative Linearity(2) –0.2 +0.2 MI(3) Vw(n + 1)–[Vw(n) + MI]

Temperature Coefficient ±300 ppm/°C See Note 5

Radiometric Temperature Coefficient ±20 ppm/°C See Note 5

CH/CL/CWPotentiometer Capacitances 10/10/25 pF See circuit #3

X9221A

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

Notes: (1) Absolute Linearity is utilized to determine actual wiper voltage versus expected voltage as determined by wiper position when used

as a potentiometer.

(2) Relative Linearity is utilized to determine the actual change in voltage between two successive tap positions when used as a poten-

tiometer. It is a measure of the error in step size.

(3) MI = RTOT/63 or (VH/RH–VL/RL)/63, single pot

ENDURANCE AND DATA RETENTION

CAPACITANCE

POWER-UP TIMING

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

(6) tPUR and tPUW are the delays required from the time VCC is stable until the speciﬁed operation can be initiated. These parameters

are periodically sampled and not 100% tested.

Power Up Requirements (Power up sequencing can affect correct recall of the wiper registers)

The preferred power-on sequence is as follows: First VCC, then the potentiometer pins. It is suggested that VCC

reach 90% of its ﬁnal value before power is applied to the potentiometer pins. The VCC ramp rate speciﬁcation

should be met, and any glitches or slope changes in the VCC line should be held to <100mV if possible. Also, VCC

should not reverse polarity by more than 0.5V.

Symbol Parameter

Limits

Test ConditionsMin. Typ. Max. Unit

lCC Supply Current (Active) 3 mA fSCL = 100kHz, SDA = Open, Other Inputs = VSS

ISB VCC Current (Standby) 200 500 µA SCL = SDA = VCC, Addr. = VSS

ILI Input Leakage Current 10 µA VIN = VSS to VCC

ILO Output Leakage Current 10 µA VOUT = VSS to VCC

VIH Input HIGH Voltage 2 VCC + 1 V

VIL Input LOW Voltage –1 0.8 V

VOL Output LOW Voltage 0.4 V IOL = 3mA

Parameter Min. Unit

Minimum endurance 100,000 Data changes per bit per register

Data retention 100 years

Symbol Parameter Max. Unit Test Conditions

CI/O(5) Input/output capacitance (SDA) 8 pF VI/O = 0V

CIN(5) Input capacitance (A0, A1, A2, A3 and SCL) 6 pF VIN = 0V

Symbol Parameter Min. Max. Unit

tPUR(6) Power-up to initiation of read operation 1 ms

tPUW(6) Power-up to initiation of write operation 5 ms

tRVCC VCC Power-up ramp rate 0.2 50 V/msec

X9221A

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SYMBOL TABLE

Equivalent A.C. Test Circuit

Circuit #3 SPICE Macro Model

Guidelines for Calculating Typical Values of Bus

Pull-Up Resistors

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

1533Ω

100pF

SDA Output

10pF

RTOTAL

25pF

10pF

Macro Model

120

100

20 40 60 80 100 120

Bus Capacitance (pF)

Min.

Resistance

Max.

Resistance

RMAX =CBUS

RMIN = IOL MIN

VCC MAX =1.8KΩ

Resistance (KΩ)

A.C. CONDITIONS OF TEST

Input pulse levels VCC x 0.1 to VCC x 0.9

Input rise and fall times 10ns

Input and output timing levels VCC x 0.5

X9221A

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

Symbol Parameter

Limits

Unit

Reference

FigureMin. Max.

fSCL SCL clock frequency 0 100 kHz 10

tLOW Clock LOW period 4700 ns 10

tHIGH Clock HIGH period 4000 ns 10

tRSCL and SDA rise time 1000 ns 10

tFSCL and SDA fall time 300 ns 10

TiNoise suppression time constant (glitch filter) 100 ns 10

tSU:STA Start condition setup time (for a repeated start condition) 4700 ns 10 & 12

tHD:STA Start condition hold time 4000 ns 10 & 12

tSU:DAT Data in setup time 250 ns 10

tHD:DAT Data in hold time 0 ns 10

tAA SCL LOW to SDA data out valid 300 3500 ns 11

tDH Data out hold time 300 ns 11

tSU:STO Stop condition setup time 4700 ns 10 & 12

tBUF Bus free time prior to new transmission 4700 ns 10

tWR Write cycle time (nonvolatile write operation) 10 ms 13

tSTPWV Wiper response time from stop generation 1000 µs 13

tCLWV Wiper response from SCL LOW 500 µs 6

X9221A

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TIMING DIAGRAMS

Figure 10. Input Bus Timing

Figure 11. Output Bus Timing

Figure 12. Start Stop Timing

Figure 13. Write Cycle and Wiper Response Timing

tHIGH

tSU:STA tHD:STA tHD:DAT tSU:DAT

tLOW tF

tSU:STO

tBUF

SCL

SDA

(Data in)

tAA tDH

SCL

SDA SDAOUT (ACK) SDAOUT SDAOUT

tSU:STO

SCL

SDA

(Data in)

tHD:STA

tSU:STA

STOP Condition START Condition

SCL

SDA

Wiper

Output

Clock 8

SDAIN

Clock 9

ACK

STOP

tWR

tSTPWV

START

X9221A

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PACKAGING INFORMATION

0.022 (0.559)

0.014 (0.356)

(3.81) 0.150

(2.92) 0.1150

0.10 (BSC)

(2.54)

1.060 (26.92)

0.980 (24.89)

0.900 (23.66)

Ref.

Pin 1 Index

0.195 (4.95)

0.115 (2.92)

––

0.015 (0.38)

Pin 1

Seating

Plane

0.070 (1.778)

0.045 (1.143)

0.280 (7.11)

0.240 (6.096)

—

0.005 (0.127)

0°

15°

20-Lead Plastic Dual In-Line Package Type P

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

2. PACKAGE DIMENSIONS EXCLUDE MOLDING FLASH

0.014 (0.356)

0.008 (0.2032)

0.300

(7.62) (BSC)

NOTE:

X9221A

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PACKAGING INFORMATION

0.290 (7.37)

0.299 (7.60)

0.393 (10.00)

0.420 (10.65)

0.014 (0.35)

0.020 (0.50)

Pin 1

Pin 1 Index

0.050 (1.27)

0.496 (12.60)

0.508 (12.90)

0.003 (0.10)

0.012 (0.30)

0.092 (2.35)

0.105 (2.65)

(4X) 7°

20-Lead Plastic Small Outline Gull Wing Package Type S

NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)

0.420"

0.050" Typical

0.050"

Typical

0.030" Typical

20 Places

FOOTPRINT

0.010 (0.25)

0.020 (0.50)

0.015 (0.40)

0.050 (1.27)

0.007 (0.18)

0.011 (0.28)

0°–8°

X 45°

X9221A

Characteristics subject to change without notice. 15 of 15

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.

REV 1.1.3 8/21/02 www.xicor.com

Ordering Information

X9221A Y P T V

VCC Limits

Blank = 5V ±10%

Temperature Range

Blank = Commercial = 0°C to +70°C

I = Industrial = –40°C to +85°C

Package

P = 20-Lead Plastic DIP

S = 20-Lead SOIC

Potentiometer Organization

Pot 0 Pot 1

Y = 2K 2K

W = 10K 10K

U = 50K 50K

Device