Digitally Controlled Potentiometer (XDCP ™ ) X9318
FEATURES •Solid-state potentiometer •3-wire rial interface
•Terminal voltage, 0 to +8V •
100 wiper tap points
—Wiper position stored in nonvolatile memory and recalled on power-up •
99 resistive elements
—Temperature compensated
—End to end resistance range ± 20% •
Low power CMOS —V CC = 5V
空调扇
—Active current, 3mA max.—Standby current, 1mA max.•
High reliability
—Endurance, 100,000 data changes per bit —Register data retention, 100 years •R TOTAL value = 10K Ω •
Packages
—8-lead SOIC and DIP
APPLICATIONS •LCD bias control •DC bias adjustment •Gain and offt trim
•Lar diode bias control生日礼物
•
Voltage regulator output control
DESCRIPTION
The Xicor X9318 is a digitally controlled potentiometer (XDCP). The device consists of a resistor array, wiper switches, a control ction, and nonvolatile memory.The wiper position is controlled by a 3-wire interface.The potentiometer is implemented by a resistor array compod of 99 resistive elements and a wiper switch-ing network. Between each element and at either end are tap points accessible to the wiper terminal. 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 subquent power-up operation.
The device can be ud as a three-terminal potentiom-eter for voltage control or as a two-terminal variable resistor for current control in a wide variety of applica-tions.
XDCP is a trademark of Xicor, Inc.
BLOCK DIAGRAM
R H
U/D INC CS V V SS
R L R W
Up/Down
(U/D)Increment
(INC) (CS)
V (Supply Voltage)
SS R H
R W R L
General
Detailed
X9318
PIN CONFIGURATION
ORDERING INFO
PIN DESCRIPTIONS Ordering
Number
RTOTAL
Package
Operating Temperature
Range
X9318WS810Kohm 8-lead SOIC 0°C to 70°C X9318WS8I 10Kohm 8-lead SOIC -40°C to +85°C X9318WP810Kohm 8-lead Plastic DIP 0°C to 70°C X9318WP8I
10Kohm
8-lead Plastic DIP
-40°C to +85°C
DIP/SOIC
Symbol
Brief Description
1INC Increment . Toggling INC while CS is low moves the wiper either up or down.2U/D Up/Down . The U/D input controls the direction of the wiper movement.
3R H The high terminal is equivalent to one of the fixed terminals of a mechanical potentiometer.4V SS Ground.
5R W The wiper terminal is equivalent to the movable terminal of a mechanical potentiometer. 6R L The low terminal is equivalent to one of the fixed terminals of a mechanical potentiometer. 7CS Chip Select . The device is lected when the CS input is LOW, and de-lected when CS is high.
8
V CC
Supply Voltage.
R H V CC INC U/D 1234
8765
X9318
DIP/SOIC
V SS
CS R L R W
Operating Temperature Range Blank = Commercial = 0°C to +70°C I = Industrial = –40°C to +85°C Package
P = 8-Lead Plastic DIP S = 8-Lead SOIC End to End Resistance W =10K Ω
X9318X X X
X9318
ABSOLUTE MAXIMUM RATINGS
Junction T emperature –65°C to +135°C –65°C to +150°C Voltage on CS, INC, U/D and V CC
with respect to –1V to +7V R H, R W, R L to ground (10)
Lead temperature (soldering 10 conds)..........300°C I W (10 conds).................................................±6mA COMMENT
Stress above tho listed under “Absolute Maximum Ratings” may cau permanent damage to the device. This is a stress rating only; functional operation of the device (at the or any other conditions above tho listed in the operational ctions of this specification) is not implied. Exposure to absolute maximum rating con-ditions for extended periods may affect device reliability.
POTENTIOMETER CHARACTERISTICS
(V CC = 5V ±10%, T A = Full Operating T emperature Range unless otherwi stated)
Symbol Parameter
Limits
Test Conditions/Notes Min.Typ.(4)Max.Unit
End to end resistance tolerance-20+20%See ordering information
for values
V RH/RL R H/R L terminal voltage V SS8V V SS = 0V
Power rating25mW
R W Wiper resistance40200ΩI W = 1mA
I W Wiper current(5)-3.0+3.0mA See test circuit
Noi(7)-120dBV Ref: 1kHz
Resolution1%
Absolute linearity(1)-1+1MI(3)V(RH) = 8V,
V(RL) = 0V Relative linearity(2)-0.2+0.2MI(3)
R TOTAL temperature coefficient(5)±300ppm/°C
Ratiometric temperature coefficient(5),(6)-20+20ppm/°C
C H/C L/C W(5)Potentiometer capacitances10/10/25pF See equivalent circuit
V CC Supply Voltage 4.5 5.5V
X9318
D.C. OPERATING CHARACTERISTICS
(V CC = 5V ±10%, T A = Full Operating T emperature Range unless otherwi stated)
ENDURANCE AND DATA RETENTION
(V CC = 5V ±10%, T A = Full Operating T emperature Range)
Notes: (1) Absolute linearity is utilized to determine actual wiper voltage versus expected voltage = [V(R W(n)(actual) )–V(R W(n)(expected) )]/MI
V(R W(n)(expected) ) = n(V(R H )-V(R L ))/99 + V(R L ), with n from 0 to 99.
邓紫棋歌(2) Relative linearity is a measure of the error in step size between taps = [V(R W(n+1) )–(V(R W(n) ) – MI)]/MI (3) 1 Ml = Minimum Increment = [V(R H )–V(R L )]/99.
(4) T ypical values are for T A = 25°C and nominal supply voltage.(5) This parameter is not 100% tested.
(6)Ratiometric temperature coefficient = (V(R W ) T1(n) –V(R W ) T2(n) )/[V(R W ) T1(n) (T1–T2) x 10 6 ], with T1 & T2 being 2 temperatures, and
n from 0 to 99.
(7)Measured with wiper at tap position 31, R L grounded, using test circuit.
Symbol
Parameter
Limits
Unit
Test Conditions
Min.Typ. (4)
Max.
I CC
V CC active current (Increment)
1
3
mA
CS = V IL , U/D = V IL or V IH
and INC = 0.4V/2.4V @ min. t CYC R L , R H , R W not connected I SB Standby supply current 3001000µA CS ≥ 2.4V, U/D and INC = 0.4V R L , R H , R W not connected I LI CS, INC, U/D input leakage cur-rent
-10+10µA V IN = V SS to V CC
V IH CS, INC, U/D input HIGH voltage 2V CC + 1V V IL CS, INC, U/D input LOW voltage –1
0.8V C IN (5)
CS, INC, U/D input capacitance
10
pF
V CC = 5V, V IN = V SS , T A = 25°C, f = 1MHz
Parameter
Min.
Unit
Minimum endurance 100,000Data changes per bit
交通标Data retention
100
Years
Test Circuit Equivalent Circuit
A.C. CONDITIONS OF TEST
Input pul levels 0.8V to 2.0V Input ri and fall times 10ns Input reference levels
1.4V
A.C. OPERATING CHARACTERISTICS
(V CC = 5V ±10%, T A = Full Operating T emperature Range unless otherwi stated)
POWER UP AND DOWN REQUIREMENTS精忠报国武术操
The recommended power up quence is to apply V CC /V SS first, then the potentiometer voltages. During power-up, the data sheet parameters for the DCP do not fully apply until 1 millicond after V CC reaches its final value.The V CC ramp spec is always in effect. In order to prevent unwanted tap position changes, or an inadvertant store,bring the CS and INC high before or concurrently with the V CC pin on powerup.A.C. TIMING
Symbol
Parameter Limits
Unit
Min.
Typ.(4)Max.t Cl CS to INC tup 100ns t lD (5)INC HIGH to U/D change 100ns t DI (5)U/D to INC tup 1µs t lL INC LOW period 1µs t lH INC HIGH period
1µs t lC INC inactive to CS inactive 1µs t CPHS CS delect time (STORE)20ms t CPHNS (5)
CS delect time (NO STORE)1µs
t IW INC to R W change 100500µs t CYC INC cycle time
4µs t R , t F (5)INC input ri and fall time
500µs t PU (5)Power up to wiper stable 500µs t R V CC (5)
V CC power-up rate
0.2
50
V/ms
PIN DESCRIPTIONS
R H and R L
The high (R H) and low (R L) terminals of the X9318 are equivalent to the fixed terminals of a mechanical potentiometer. The terminology of R L and R H refer-ences the relative position of the terminal in relation to wiper movement direction lected by the U/D input and not the voltage potential on the terminal.
R
W
R w is the wiper terminal and is equivalent to the mov-able terminal of a mechanical potentiometer. The posi-tion of the wiper within the array is determined by the control inputs. The wiper terminal ries resistance is typically 40Ω.
Up/Down (U/D)
The U/D input controls the direction of the wiper move-ment and whether the counter is incremented or decre-mented.
Increment (INC)
The INC input is negative-edge triggered. T oggling 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.
健康礼品Chip Select (CS)
The device is lected 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 X9318 will be placed in the low power standby mode until the device is lected once again.
PIN CONFIGURATION PIN NAMES
PRINCIPLES OF OPERATION
There are three ctions of the X9318: the control ction, the nonvolatile memory, and the resistor array. The control ction 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. The contents of the counter can be stored in nonvolatile memory and retained for future u. The resistor array is comprid of 99 individual resistors connected in ries. Electronic switches at either end of the array and between each resistor provide an electrical connection to the wiper pin, R W.
The wiper acts like its mechanical equivalent and does not move beyond the first or 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 veral 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 veral 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 t to the value last stored.
R H V CC
INC U/D 1
2
3
4
8
7
6
5
X9318
DIP/SOIC
V SS CS
R L
R W
Symbol Description
R H High terminal
R W Wiper terminal
熊猫烧香病毒下载R L Low terminal
V SS Ground
圣诞节活动策划方案V CC Supply voltage
U/D Up/Down control input
INC Increment control input
CS Chip lect control input
