X9269UB24I [RENESAS]

Digital Potentiometer, 2 Func, 50000ohm, 2-wire Serial Control Interface, 256 Positions, CMOS, PBGA24, XBGA-24;
X9269UB24I
型号: X9269UB24I
厂家: RENESAS TECHNOLOGY CORP    RENESAS TECHNOLOGY CORP
描述:

Digital Potentiometer, 2 Func, 50000ohm, 2-wire Serial Control Interface, 256 Positions, CMOS, PBGA24, XBGA-24

文件: 总24页 (文件大小:146K)
中文:  中文翻译
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APPLICATION NOTES AND DEVELOPMENT SYSTEM  
A V A I L A B L E  
AN99 • AN115 • AN124 •AN133 • AN134 • AN135  
Single Supply / Low Power / 256-tap / 2-Wire bus  
X9269  
Dual Digitally-Controlled (XDCPTM) Potentiometers  
FEATURES  
DESCRIPTION  
• Dual–Two separate potentiometers  
• 256 resistor taps/pot–0.4% resolution  
• 2-Wire Serial Interface for write, read, and  
transfer operations of the potentiometer  
Wiper Resistance, 100typical @ V+ = 5V, V- = -5V  
• 16 Nonvolatile Data Registers for Each  
Potentiometer  
• Nonvolatile Storage of Multiple Wiper Positions  
• Power On Recall. Loads Saved Wiper Position on  
Power Up.  
• Standby Current < 5µA Max  
• 50K, 100Kversions of End to End Pot  
Resistance  
• Endurance: 100,000 Data Changes per Bit per  
Register  
• 100 yr. Data Retention  
• 24-Lead SOIC, 24-Lead XBGA  
• Low Power CMOS  
The X9269 integrates  
potentiometer (XDCP) on  
integrated circuit.  
2
digitally controlled  
monolithic CMOS  
a
The digital controlled potentiometer is implemented  
using 255 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 a four nonvolatile Data Registers 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 though the switches. Powerup  
recalls the contents of the default Data Register (DR0)  
to the WCR.  
The XDCP can be used as  
a three-terminal  
• Power Supply V  
= 2.7V to 5.5V  
potentiometer or as a two terminal variable resistor in  
a wide variety of applications including control,  
parameter adjustments, and signal processing.  
CC  
FUNCTIONAL DIAGRAM  
V
R
R
H1  
CC  
H0  
Write  
Read  
Address  
Data  
Status  
Transfer  
Inc/Dec  
Power On Recall  
Bus  
2-Wire  
Wiper Counter  
Registers (WCR)  
Bus  
Interface  
and Control  
Interface  
Data Registers  
(DR0–DR3)  
Control  
V
R
R
R
R
L1  
SS  
W0  
L0  
W1  
50Kor 100Kversions  
Characteristics subject to change without notice. 1 of 24  
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X9269  
DETAILED FUNCTIONAL DIAGRAM  
R
R
R
H0  
L0 W0  
V
CC  
Power On  
Recall  
Pot 0  
R
R
0
1
Wiper  
Counter  
Register  
(WCR)  
R
R
2
3
SCL  
SDA  
INTERFACE  
AND  
50Kand 100KΩ  
A3  
A2  
A1  
CONTROL  
CIRCUITRY  
256-taps  
8
Power On  
Recall  
A0  
Data  
WP  
R
R
0
1
Wiper  
Counter  
Register  
(WCR)  
Resistor  
Array  
Pot 1  
R
R
2
3
V
SS  
R
R
R
L1 H1 W1  
CIRCUIT LEVEL APPLICATIONS  
SYSTEM LEVEL APPLICATIONS  
• Vary the gain of a voltage amplifier  
• Adjust the contrast in LCD displays  
• Provide programmable dc reference voltages for  
comparators and detectors  
• Control the power level of LED transmitters in  
communication systems  
• Control the volume in audio circuits  
• Set and regulate the DC biasing point in an RF power  
amplifier in wireless systems  
Trim out the offset voltage error in a voltage amplifier  
circuit  
• Control the gain in audio and home entertainment  
systems  
• Set the output voltage of a voltage regulator  
• Provide the variable DC bias for tuners in RF wireless  
systems  
Trim the resistance in Wheatstone bridge circuits  
• Control the gain, characteristic frequency and  
Q-factor in filter circuits  
• Set the operating points in temperature control  
systems  
• Set the scale factor and zero point in sensor signal  
conditioning circuits  
• Control the operating point for sensors in industrial  
systems  
• Vary the frequency and duty cycle of timer ICs  
Trim offset and gain errors in artificial intelligent  
systems  
• Vary the dc biasing of a pin diode attenuator in RF  
circuits  
• Provide a control variable (I, V, or R) in feedback  
circuits  
Characteristics subject to change without notice. 2 of 24  
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X9269  
PIN CONFIGURATION  
SOIC  
XBGA  
1
2
3
4
NC  
SCL  
NC  
NC  
NC  
NC  
NC  
1
2
24  
23  
22  
21  
20  
19  
18  
17  
16  
A0  
A
B
NC  
3
Not Available  
NC  
NC  
NC  
4
5
6
X9269  
C
D
V
V
7
CC  
SS  
R
R
8
W1  
L0  
R
R
H0  
9
H1  
R
R
W0  
A2  
10  
11  
12  
15  
14  
L1  
E
F
A1  
WP  
13  
SDA  
Top View–Bumps Down  
PIN ASSIGNMENTS  
Pin  
Pin  
(XBGA)  
(SOIC)  
Symbol  
NC  
Function  
1
No Connect  
2
A0  
Device Address for 2-Wire bus.  
No Connect  
3
NC  
4
NC  
No Connect  
5
NC  
No Connect  
6
NC  
No Connect  
7
V
System Supply Voltage  
Low Terminal for Potentiometer 0.  
High Terminal for Potentiometer 0.  
Wiper Terminal for Potentiometer 0.  
Device Address for 2-Wire bus.  
Hardware Write Protect  
Serial Data Input/Output for 2-Wire bus.  
Device Address for 2-Wire bus.  
Low Terminal for Potentiometer 1.  
High Terminal for Potentiometer 1.  
Wiper Terminal for Potentiometer 1.  
System Ground  
CC  
8
R
L0  
H0  
W0  
9
R
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
21  
22  
23  
24  
R
A2  
WP  
SDA  
A1  
R
L1  
H1  
W1  
R
R
V
SS  
NC  
NC  
NC  
NC  
SCL  
A3  
No Connect  
No Connect  
No Connect  
No Connect  
Serial Clock for 2-Wire bus.  
Device Address for 2-Wire bus.  
Characteristics subject to change without notice. 3 of 24  
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X9269  
PIN DESCRIPTIONS  
Potentiometer Pins  
R , R  
Bus Interface Pins  
H
L
The R and R pins are equivalent to the terminal  
H
L
SERIAL DATA INPUT/OUTPUT (SDA)  
connections on a mechanical potentiometer. Since  
there are 2 potentiometers, there are 2 sets of R and  
The SDA is a bidirectional serial data input/output pin  
for a 2-Wire slave device and is used to transfer data  
into and out of the device. It receives device address,  
opcode, wiper register address and data sent from an  
2-Wire master at the rising edge of the serial clock  
SCL, and it shifts out data after each falling edge of the  
serial clock SCL.  
H
R such that R and R are the terminals of POT 0  
L
H0  
L0  
and so on.  
R
W
The wiper pin are equivalent to the wiper terminal of a  
mechanical potentiometer. Since there are  
4
potentiometers, there are 2 sets of R such that R  
is the terminal of POT 0 and so on.  
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 values, refer to the guidelines for  
calculating typical values on the bus pull-up resistors  
graph.  
W
W0  
Bias Supply Pins  
SYSTEM SUPPLY VOLTAGE (V  
) AND SUPPLY GROUND (V  
SS  
)
CC  
The V pin is the system supply voltage. The V pin  
is the system ground.  
CC  
SS  
SERIAL CLOCK (SCL)  
This input is used by 2-Wire master to supply 2-Wire  
serial clock to the X9269.  
Other Pins  
NO CONNECT  
DEVICE ADDRESS (A3–A0)  
No connect pins should be left open. This pins are used for  
Xicor manufacturing and testing purposes.  
The address inputs are used to set the least significant  
3 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 X9269. A maximum of 8 devices may occupy the 2-  
Wire serial bus.  
HARDWARE WRITE PROTECT INPUT (WP)  
The WP pin when LOW prevents nonvolatile writes to  
the Data Registers.  
Characteristics subject to change without notice. 4 of 24  
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X9269  
PRINCIPLES OF OPERATION  
These switches are controlled by a Wiper Counter  
Register (WCR). The 8-bits of the WCR (WCR[7:0])  
are decoded to select, and enable, one of 256 switches  
(see Table 1).  
The X9269 is a integrated microcircuit incorporating  
four resistor arrays and their associated registers and  
counters and the serial interface logic providing direct  
communication between the host and the digitally  
controlled potentiometers. This section provides detail  
description of the following:  
The WCR may be written directly. These Data  
Registers can the WCR can be read and written by the  
host system.  
– Resistor Array Description  
Power Up and Down Requirements.  
There are no restrictions on the power-up or power-  
– Serial Interface Description  
– Instruction and Register Description.  
down conditions of V and the voltages applied to the  
CC  
potentiometer pins provided that V  
is always more  
CC  
Array Description  
positive than or equal to V , V , and V , i.e., V V ,  
H L W CC H  
V , V . The V ramp rate specification is always in  
CC  
The X9269 is comprised of a resistor array (see Figure  
1). Each array contains 255 discrete resistive  
segments that are connected in series. The physical  
ends of each array are equivalent to the fixed terminals  
L
W
effect.  
of a mechanical potentiometer (R and R inputs).  
H
L
At both ends of each array and between each resistor  
segment is a CMOS switch connected to the wiper  
(R ) output. Within each individual array only one  
W
switch may be turned on at a time.  
Figure 1. Detailed Potentiometer Block Diagram  
One of Two Potentiometers  
SERIAL DATA PATH  
SERIAL  
R
H
BUS  
FROM INTERFACE  
CIRCUITRY  
INPUT  
C
O
U
N
T
REGISTER 0  
(DR0)  
REGISTER 1  
(DR1)  
8
8
PARALLEL  
BUS  
INPUT  
E
R
REGISTER 2  
(DR2)  
REGISTER 3  
(DR3)  
D
E
C
O
D
E
WIPER  
COUNTER  
REGISTER  
(WCR)  
INC/DEC  
LOGIC  
IF WCR = 00[H] THEN R = R  
W
L
UP/DN  
UP/DN  
CLK  
IF WCR = FF[H] THEN R = R  
W
H
R
R
MODIFIED SCL  
L
W
Characteristics subject to change without notice. 5 of 24  
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X9269  
SERIAL INTERFACE DESCRIPTION  
Serial Interface  
Stop Condition  
All communications must be terminated by a stop  
condition, which is a LOW to HIGH transition of SDA  
while SCL is HIGH. See Figure 2.  
The X9269 supports a bidirectional bus oriented  
protocol. 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 provide the clock for both transmit and receive  
operations. Therefore, the X9269 will be considered a  
slave device in all applications.  
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  
during this period the receiver pulls the SDA line LOW  
to acknowledge that it successfully received the eight  
bits of data.  
Clock and Data Conventions  
Data states on the SDA line can change only during  
SCL LOW periods. SDA state changes during SCL  
HIGH are reserved for indicating start and stop  
conditions. See Figure 2.  
The X9269 will respond with an acknowledge after  
recognition of a start condition and its slave address  
and once again after successful receipt of the  
command byte. If the command is followed by a data  
byte the X9269 will respond with a final acknowledge.  
See Figure 2.  
Start Condition  
All commands to the X9269 are preceded by the start  
condition, which is a HIGH to LOW transition of SDA  
while SCL is HIGH. The X9269 continuously monitors  
the SDA and SCL lines for the start condition and will  
not respond to any command until this condition is met.  
See Figure 2.  
Figure 2. Acknowledge Response from Receiver  
SCL FROM  
MASTER  
1
8
9
DATA  
OUTPUT  
FROM  
TRANSMITTER  
DATA  
OUTPUT  
FROM  
RECEIVER  
START  
ACKNOWLEDGE  
Characteristics subject to change without notice. 6 of 24  
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X9269  
Acknowledge Polling  
INSTRUCTION AND REGISTER DESCRIPTION  
Instructions  
The disabling of the inputs, during the internal  
nonvolatile 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 nonvolatile write command the X9269  
initiates the internal write cycle. ACK polling, Flow 1,  
can be initiated immediately. This involves issuing the  
start condition followed by the device slave address. If  
the X9269 is still busy with the write operation no ACK  
will be returned. If the X9269 has completed the write  
operation an ACK will be returned and the master can  
then proceed with the next operation.  
DEVICE ADDRESSING: IDENTIFICATION BYTE (ID AND A)  
The first byte sent to the X9269 from the host is called  
the Identification Byte. The most significant four bits of  
the slave address are a device type identifier. The  
ID[3:0] bits is the device id for the X9269; this is fixed  
as 0101[B] (refer to Table 1).  
The A[3:0] bits in the ID byte is the internal slave  
address. The physical device address is defined by  
the state of the A3-A0 input pins. The slave address is  
externally specified by the user. The X9269 compares  
the serial data stream with the address input state; a  
successful compare of both address bits is required  
for the X9269 to successfully continue the command  
sequence. Only the device which slave address  
matches the incoming device address sent by the  
master executes the instruction. The A3-A0 inputs  
can be actively driven by CMOS input signals or tied  
FLOW 1: ACK Polling Sequence  
Nonvolatile Write  
Command Completed  
EnterACK Polling  
Issue  
START  
to V  
or V  
.
CC  
SS  
INSTRUCTION BYTE (I)  
Issue Slave  
Issue STOP  
Address  
The next byte sent to the X9269 contains the  
instruction and register pointer information. The three  
most significant bits are used provide the instruction  
opcode I [3:0]. The RB and RA bits point to one of the  
four Data Registers of each associated XDCP. The  
least significant bit points to one of two Wiper Counter  
Registers or Pots.The format is shown in Table 2.  
ACK  
Returned?  
No  
Yes  
No  
Further  
Operation?  
Register Selection  
Yes  
Register Selected  
RB  
0
RA  
0
Issue  
Instruction  
DR0  
DR1  
DR2  
DR3  
Issue STOP  
Proceed  
0
1
1
0
Proceed  
1
1
Characteristics subject to change without notice. 7 of 24  
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X9269  
Table 1. Identification Byte Format  
Device Type  
Identifier  
Slave Address  
ID3  
0
ID2  
1
ID1  
0
ID0  
1
A3  
A2  
A1  
A0  
(MSB)  
(LSB)  
Table 2. Instruction Byte Format  
Instruction  
Opcode  
Register  
Selection  
Pot Selection  
(WCR Selection)  
I3  
I2  
I1  
I0  
RB  
RA  
0
P0  
(MSB)  
(LSB)  
Table 3. Instruction Set  
Instruction  
Instruction Set  
I3 I2 I1 I0 RB RA  
0
P0  
Operation  
Read Wiper Counter  
Register  
1
1
1
1
1
0
0
0
1
1
0
1
1
0
0
1
0
1
0
1
0
0
0
1/0 Read the contents of the Wiper Counter  
Register pointed to by P0  
Write Wiper Counter Register  
0
0
0
0
0
0
1/0 Write new value to the Wiper Counter  
Register pointed to by P0  
Read Data Register  
1/0 1/0  
1/0 1/0  
1/0 1/0  
1/0 Read the contents of the Data Register  
pointed to by P0 and RB-RA  
Write Data Register  
1/0 Write new value to the Data Register  
pointed to by P0 and RB-RA  
XFR Data Register to Wiper  
Counter Register  
1/0 Transfer the contents of the Data Register  
pointed to by P0 and RB-RA to its  
associated Wiper Counter Register  
XFR Wiper Counter Register  
to Data Register  
1
0
1
0
1
0
0
0
1
0
0
1
0
1
0
0
1/0 1/0  
1/0 1/0  
1/0 1/0  
0
0
0
0
1/0 Transfer the contents of the Wiper Counter  
Register pointed to by P0 to the Data Reg-  
ister pointed to by RB-RA  
Global XFR Data Registers  
to Wiper Counter Registers  
0
Transfer the contents of the Data Registers  
pointed to by RB-RA of all four pots to their  
respective Wiper Counter Registers  
Global XFR Wiper Counter  
Registers to Data Register  
0
Transfer the contents of both Wiper Counter  
Registers to their respective data Registers  
pointed to by RB-RA of all four pots  
Increment/Decrement Wiper  
Counter Register  
0
0
1/0 Enable Increment/decrement of the Control  
Latch pointed to by P0  
Note: 1/0 = data is one or zero  
Characteristics subject to change without notice. 8 of 24  
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X9269  
DEVICE DESCRIPTION  
Data Registers (DR)  
Each potentiometer has four 8-bit nonvolatile Data  
Registers. These can be read or written directly by the  
host. Data can also be transferred between any of the  
four Data Registers and the associated Wiper Counter  
Register. All operations changing data in one of the  
data registers is a nonvolatile operation and will take a  
maximum of 10ms.  
Wiper Counter Register (WCR)  
The X9269 contains two Wiper Counter Registers, one  
for each DCP potentiometer. The Wiper Counter  
Register can be envisioned as a 8-bit parallel and  
serial load counter with its outputs decoded to select  
one of 256 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 Wiper  
Counter Register 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 (see Instruction section for more details).  
Finally, it is loaded with the contents of its Data  
Register zero (DR0) upon power-up.  
If the application does not require storage of multiple  
settings for the potentiometer, the Data Registers can  
be used as regular memory locations for system  
parameters or user preference data.  
Bit [7:0] are used to store one of the 256 wiper  
positions (0~255).  
The Wiper Counter Register is a volatile register; that  
is, its contents are lost when the X9269 is powered-  
down. Although the register is automatically loaded  
with the value in DR0 upon power-up, this may be  
different from the value present at power-down. Power-  
up guidelines are recommended to ensure proper  
loadings of the DR0 value into the WCR (See Design  
Considerations Section).  
Table 1. Wiper counter Register, WCR (8-bit), WCR[7:0]: Used to store the current wiper position (Volatile, V).  
WCR7  
V
WCR6  
V
WCR5  
V
WCR4  
V
WCR3  
V
WCR2  
V
WCR1  
V
WCR0  
V
(MSB)  
(LSB)  
Table 2. Data Register, DR (8-bit), Bit [7:0]: Used to store wiper positions or data (Nonvolatile, NV).  
Bit 7  
NV  
Bit 6  
NV  
Bit 5  
NV  
Bit 4  
NV  
Bit 3  
NV  
Bit 2  
NV  
Bit 1  
NV  
Bit 0  
NV  
MSB  
LSB  
Characteristics subject to change without notice. 9 of 24  
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X9269  
DEVICE DESCRIPTION  
Instructions  
XFR Data Register to Wiper Counter Register –  
This transfers the contents of one specified Data  
Register to the associated Wiper Counter Register.  
Four of the nine instructions are three bytes in length.  
These instructions are:  
XFR Wiper Counter Register to Data Register –  
This transfers the contents of the specified Wiper  
Counter Register to the specified associated Data  
Register.  
Read Wiper Counter Register – read the current  
wiper position of the selected potentiometer,  
Global XFR Data Register to Wiper Counter  
Register – This transfers the contents of all specified  
Data Registers to the associated Wiper Counter Reg-  
isters.  
Write Wiper Counter Register – change current  
wiper position of the selected potentiometer,  
Read Data Register – read the contents of the  
selected Data Register;  
Global XFR Wiper Counter Register to Data  
Register – This transfers the contents of all Wiper  
Counter Registers to the specified associated Data  
Registers.  
Write Data Register – write a new value to the  
selected Data Register.  
The basic sequence of the three byte instructions is  
illustrated in Figure 4. These three-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, with the static RAM  
controlling the wiper position. The response of the  
INCREMENT/DECREMENT COMMAND  
The final command is Increment/Decrement (Figure 5  
and 6). The Increment/Decrement command is different  
from the other commands. Once the command is  
issued and the X9269 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  
wiper to this action will be delayed by t  
. A transfer  
WRL  
from the WCR (current wiper position), to a Data  
Register is a write to nonvolatile memory and takes a  
minimum of t  
to complete. The transfer can occur  
WR  
between one of the four potentiometers and one of its  
associated registers; or it may occur globally, where the  
transfer occurs between all potentiometers and one  
associated register  
SCL clock pulse (t  
) while SDA is HIGH, the  
HIGH  
selected wiper will move one resistor segment towards  
the R terminal. Similarly, for each SCL clock pulse  
H
while SDA is LOW, the selected wiper will move one  
resistor segment towards the R terminal.  
Four instructions require a two-byte sequence to  
complete. These instructions transfer data between the  
host and the X9269; either between the host and one of  
the data registers or directly between the host and the  
Wiper Counter Register.These instructions are:  
L
See Instruction format for more details.  
Characteristics subject to change without notice. 10 of 24  
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X9269  
Figure 3. Two-Byte Instruction Sequence  
SCL  
SDA  
0
1
0
1
ID3 ID2 ID1 ID0  
S
A2 A1 A0  
S
T
A
R
T
A3  
A I3 I2 I1  
I0  
RB RA 0 P0  
A
C
K
C
K
T
O
P
Internal  
Address  
Instruction  
Opcode  
Register  
Address  
Pot/WCR  
Address  
Device ID  
Figure 4. Three-Byte Instruction Sequence  
SCL  
SDA  
0
1
0
1
0
0
S
T
A
R
T
I3  
A
C
K
I1  
P0  
A
C
K
D7 D6 D5 D4 D3 D2 D1 D0  
A
C
K
S
T
ID3 ID2  
ID0  
I2  
I0 RB RA  
ID1  
A3 A2 A1 A0  
O
P
Internal  
Address  
Device ID  
WCR[7:0]  
or  
Data Register D[7:0]  
Instruction  
Opcode  
Register  
Address  
Pot/WCR  
Address  
Figure 5. Increment/Decrement Instruction Sequence  
SCL  
0
1
0
1
SDA  
0
ID3 ID2 ID1 ID0  
Device ID  
I1  
A3 A2 A1 A0  
I3  
I2  
I0  
RB RA 0  
P0  
S
T
A
R
T
A
C
K
A
C
K
I
I
D
E
C
1
S
I
D
N
C
1
N
C
2
T
O
P
N
C
n
E
C
n
Internal  
Address  
Instruction  
Opcode  
Pot/WCR  
Address  
Register  
Address  
Figure 6. Increment/Decrement Timing Limits  
INC/DEC  
CMD  
Issued  
t
WRID  
SCL  
SDA  
Voltage Out  
R
W
Characteristics subject to change without notice. 11 of 24  
REV 1.1.3 4/3/01  
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X9269  
INSTRUCTION FORMAT  
Read Wiper Counter Register (WCR)  
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
Wiper Position  
(Sent by X9269 on SDA)  
S
T
A
R
T
S
A
C
K
S
A
C
K
M S  
A T  
C O  
K P  
W
C
R
W
C
R
7
W W W W W W  
C C C C C C  
R R R R R R  
0
1
0
1 A3 A2 A1 A0  
1
0
0
1
0
0
0
P0  
5
4 3 2 1 0  
6
Write Wiper Counter Register (WCR)  
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
Wiper Position  
(Sent by Master on SDA)  
S
T
A
R
T
S
A
C
K
S
A
C
K
S S  
A T  
C O  
K P  
W
C
W
C
R
7
W W W W W W  
C C C C C C  
R R R R R R  
0
1
0
1 A3 A2 A1 A0  
1
0
1
0
0
0
0
P0  
R
5
4 3 2 1 0  
6
Read Data Register (DR)  
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
Wiper Position  
(Sent by X9269 on SDA)  
S
T
A
R
T
S
A
C
K
S
A
C
K
M S  
A T  
C O  
K P  
W
C
W
C
R
7
W W W W W W  
C C C C C C  
R R R R R R  
0
1
0
1 A3 A2 A1 A0  
1
0
1
1 RB RA  
0
P0  
R
5
4 3 2 1 0  
6
Write Data Register (DR)  
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
Wiper Position  
(Sent by Master on SDA)  
S
T
A
R
T
S
A
C
K
S
S S  
A T  
C O  
K P  
A
C
K
W
C
W
C
R
7
W W W W W W  
C C C C C C  
R R R R R R  
5 4 3 2 1 0  
0
1
0
1 A3 A2 A1 A0  
1 1 0 0 RB RA  
0
P0  
R
6
Global XFR Data Register (DR) to Wiper Counter Register (WCR)  
S
T
A
R
T
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
S
A
C
K
S S  
A T  
C O  
K P  
0
1
0
1
A3 A2 A1 A0  
0
0
0
1
RB RA  
0
0
Characteristics subject to change without notice. 12 of 24  
REV 1.1.3 4/3/01  
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X9269  
Global XFR Wiper Counter Register (WCR) to Data Register (DR)  
S
T
A
R
T
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
S
A
C
K
S S  
A T  
C O  
K P  
HIGH-VOLTAGE  
WRITE CYCLE  
0
1
0
1 A3 A2 A1 A0  
1 0 0 0 RB RA 0  
0
Transfer Wiper Counter Register (WCR) to Data Register (DR)  
S
T
A
R
T
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
S
A
C
K
S S  
A T HIGH-VOLTAGE  
C O WRITE CYCLE  
P0  
K P  
0
1
0
1 A3 A2 A1 A0  
1 1 1 0 RB RA  
0
Transfer Data Register (DR) to Wiper Counter Register (WCR)  
S
T
A
R
T
Device Type  
Identifier  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
S
A
C
K
S S  
A T  
C O  
K P  
0
1
0
1
A3 A2 A1 A0  
1 1 0 1 RB RA  
0
P0  
Increment/Decrement Wiper Counter Register (WCR)  
S Device Type  
Device  
Addresses  
Instruction  
Opcode  
DR/WCR  
Addresses  
Increment/Decrement  
(Sent by Master on SDA)  
S
A
C
K
S
A
C
K
S
T
O
P
T
A
R
T
Identifier  
0
1
0
1 A3 A2 A1 A0  
0
0
1
0
0
0
0
P0  
I/D I/D  
.
.
.
.
I/D I/D  
Notes: (1) “MACK”/”SACK”: stands for the acknowledge sent by the master/slave.  
(2) “A3 ~ A0”: stands for the device addresses sent by the master.  
(3) “X”: indicates that it is a “0” for testing purpose but physically it is a “don’t care” condition.  
(4) “I”: stands for the increment operation, SDA held high during active SCL phase (high).  
(5) “D”: stands for the decrement operation, SDA held low during active SCL phase (high).  
Characteristics subject to change without notice. 13 of 24  
REV 1.1.3 4/3/01  
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X9269  
ABSOLUTE MAXIMUM RATINGS  
COMMENT  
Temperature under bias ....................–65°C to +135°C  
Storage temperature .........................–65°C to +150°C  
Voltage on SCL, SDA any address input  
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.  
with respect to V ..................................1V to +7V  
SS  
V = | (V –V ) |.................................................... 5.5V  
H
L
Lead temperature (soldering, 10 seconds).........300°C  
I
(10 seconds) ................................................. 6mA  
W
RECOMMENDED OPERATING CONDITIONS  
Temp  
Commercial  
Industrial  
Min.  
0°C  
Max.  
+70°C  
+85°C  
Device  
X9269  
Supply Voltage (V  
)
(4) Limits  
CC  
5V 10%  
–40°C  
X9269-2.7  
2.7V to 5.5V  
POTENTIOMETER CHARACTERISTICS (Over recommended industrial (2.7V) operating conditions unless otherwise stated.)  
Limits  
Symbol  
Parameter  
End to End Resistance  
End to End Resistance  
Min.  
Typ.  
100  
50  
Max.  
Units  
kΩ  
kΩ  
Test Conditions  
T version  
R
TOTAL  
R
U version  
TOTAL  
End to End Resistance  
Tolerance  
20  
%
Power Rating  
50  
3
mW  
mA  
25°C, each pot  
I
Wiper Current  
W
R
R
Wiper Resistance  
Wiper Resistance  
300  
150  
I
I
=
=
3mA @ V+ = 3V; V- = -3V  
3mA @ V+ = 5V; V- = -5V  
W
W
W
W
V
Voltage on any R or R Pin  
V
V
V
V
= 0V  
TERM  
H
L
SS  
CC  
SS  
Noise  
-120  
0.4  
dBV  
%
Ref: 1V  
Resolution  
(5)  
Absolute Linearity (1)  
1
MI(3)  
R
– R  
w(n)(actual) w(n)(expected)  
(5)  
Relative Linearity (2)  
0.2  
20  
MI(3)  
R
– [R  
]
w(n + 1)  
w(n) + MI  
Temperature Coefficient of  
300  
ppm/°C  
R
TOTAL  
Ratiometric Temp. Coefficient  
Potentiometer Capacitances  
ppm/°C  
pF  
C /C /C  
W
10/10/25  
See Macro model  
H
L
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  
potentiometer. It is a measure of the error in step size.  
(3) MI = RTOT / 255 or (R – R ) / 255, single pot  
H
L
(4) During power up V > V , V , and V .  
CC  
H
L
W
(5) n = 0, 1, 2, …,255; m =0, 1, 2, …, 254.  
Characteristics subject to change without notice. 14 of 24  
REV 1.1.3 4/3/01  
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X9269  
D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.)  
Limits  
Symbol  
Parameter  
Min.  
Typ.  
Max.  
Units  
Test Conditions  
= 400KHz; V = +6V;  
SDA = Open; (for 2-Wire, Active, Read  
and  
I
I
I
V
supply current  
(active)  
3
mA  
f
SCL  
CC1  
CC2  
SB  
CC  
CC  
V
supply current  
(nonvolatile write)  
5
5
mA  
f
= 400KHz; V = +6V;  
CC  
SCL CC  
SDA = Open; (for 2-Wire, Active,  
Nonvolatile Write State only)  
V
current (standby)  
µA  
V
V
= +6V; V = V or V ; SDA =  
IN SS CC  
; (for 2-Wire, Standby State only)  
CC  
CC  
CC  
I
I
Input leakage current  
Output leakage current  
Input HIGH voltage  
Input LOW voltage  
10  
10  
µA  
µA  
V
V
V
= V to V  
LI  
IN  
SS  
CC  
= V to V  
CC  
LO  
OUT  
SS  
V
V
V
V
V
x 0.7  
V
+ 1  
CC  
IH  
CC  
–1  
V
x 0.3  
CC  
V
IL  
Output LOW voltage  
Output HIGH voltage  
0.4  
V
I
= 3mA  
OL  
OL  
OH  
ENDURANCE AND DATA RETENTION  
Parameter  
Minimum endurance  
Data retention  
Min.  
Units  
100,000  
100  
Data changes per bit per register  
years  
CAPACITANCE  
Symbol  
Test  
Input / Output capacitance (SDA)  
Input capacitance (SCL, WP, A3, A2, A1 and A0)  
Max.  
Units  
pF  
Test Conditions  
= 0V  
(6)  
C
C
8
6
V
OUT  
IN/OUT  
(6)  
pF  
V
= 0V  
IN  
IN  
POWER-UP TIMING  
Symbol  
Parameter  
V Power-up rate  
CC  
Min.  
Max.  
50  
Units  
V/ms  
ms  
(6)  
t V  
0.2  
r
CC  
(7)  
t
Power-up to initiation of read operation  
1
PUR  
POWER UP AND DOWN REQUIREMENTS  
The are no restrictions on the power-up or power-down conditions of V  
and the voltages applied to the poten-  
CC  
tiometer pins provided that V is always more positive than or equal to V , V , and V , i.e., V V , V , V .The  
CC  
H
L
W
CC  
H
L
W
V
ramp rate spec is always in effect.  
CC  
A.C. TEST CONDITIONS  
Input Pulse Levels  
V
x 0.1 to V x 0.9  
CC  
CC  
Input rise and fall times  
Input and output timing level  
10ns  
V
x 0.5  
CC  
Notes: (6) This parameter is not 100% tested  
(7) t and t are the delays required from the time the (last) power supply (V -) is stable until the specific instruction can be  
PUR  
PUW  
CC  
issued.These parameters are periodically sampled and not 100% tested.  
Characteristics subject to change without notice. 15 of 24  
REV 1.1.3 4/3/01  
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X9269  
EQUIVALENT A.C. LOAD CIRCUIT  
5V  
3V  
SPICE Macromodel  
1533Ω  
867Ω  
R
TOTAL  
R
R
L
H
SDA pin  
SDA pin  
C
C
W
C
L
L
10pF  
100pF  
100pF  
25pF  
10pF  
R
W
AC TIMING  
Symbol  
Parameter  
Min.  
Max.  
Units  
kHz  
ns  
f
t
t
t
t
t
t
t
t
t
t
t
t
Clock Frequency  
Clock Cycle Time  
Clock High Time  
Clock Low Time  
Start Setup Time  
Start Hold Time  
Stop Setup Time  
400  
SCL  
2500  
600  
1300  
600  
600  
600  
100  
30  
CYC  
ns  
HIGH  
LOW  
SU:STA  
HD:STA  
SU:STO  
SU:DAT  
HD:DAT  
R
ns  
ns  
ns  
ns  
SDA Data Input Setup Time  
SDA Data Input Hold Time  
SCL and SDA Rise Time  
SCL and SDA Fall Time  
ns  
ns  
300  
300  
0.9  
ns  
ns  
F
SCL Low to SDA Data Output Valid Time  
SDA Data Output Hold Time  
µs  
ns  
AA  
0
50  
1200  
0
DH  
T
Noise Suppression Time Constant at SCL and SDA inputs  
Bus Free Time (Prior to Any Transmission)  
A0, A1 Setup Time  
ns  
I
t
t
t
ns  
BUF  
ns  
SU:WPA  
HD:WPA  
A0, A1 Hold Time  
0
ns  
Characteristics subject to change without notice. 16 of 24  
REV 1.1.3 4/3/01  
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X9269  
HIGH-VOLTAGE WRITE CYCLE TIMING  
Symbol  
Parameter  
Typ.  
Max.  
Units  
t
High-voltage write cycle time (store instructions)  
5
10  
ms  
WR  
XDCP TIMING  
Symbol  
Parameter  
Min. Max. Units  
t
t
Wiper response time after the third (last) power supply is stable  
Wiper response time after instruction issued (all load instructions)  
5
5
10  
10  
µs  
µs  
WRPO  
WRL  
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  
.
Characteristics subject to change without notice. 17 of 24  
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X9269  
TIMING DIAGRAMS  
Start and Stop Timing  
(START)  
(STOP)  
t
t
F
R
SCL  
t
t
t
SU:STO  
SU:STA  
HD:STA  
t
t
F
R
SDA  
Input Timing  
t
t
CYC  
HIGH  
SCL  
SDA  
t
LOW  
t
t
t
BUF  
SU:DAT  
HD:DAT  
Output Timing  
SCL  
SDA  
t
t
DH  
AA  
Characteristics subject to change without notice. 18 of 24  
REV 1.1.3 4/3/01  
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X9269  
XDCP Timing (for All Load Instructions)  
(STOP)  
SCL  
SDA  
VWx  
LSB  
t
WRL  
Write Protect and Device Address Pins Timing  
(START)  
(STOP)  
SCL  
...  
(Any Instruction)  
...  
SDA  
...  
t
t
SU:WPA  
HD:WPA  
WP  
A0, A1  
Characteristics subject to change without notice. 19 of 24  
REV 1.1.3 4/3/01  
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X9269  
APPLICATIONS INFORMATION  
Basic Configurations of Electronic Potentiometers  
+V  
R
V
R
RW  
I
Three terminal Potentiometer;  
Variable voltage divider  
Two terminal Variable Resistor;  
Variable current  
Application Circuits  
Noninverting Amplifier  
Voltage Regulator  
V
+
S
V
V
V (REG)  
O
317  
O
IN  
R
1
R
2
I
adj  
R
R
1
2
V
= (1+R /R )V  
V
(REG) = 1.25V (1+R /R )+I  
R
adj 2  
O
2
1
S
O
2
1
Offset Voltage Adjustment  
Comparator with Hysterisis  
R
R
2
1
V
+
S
V
V
S
O
100KΩ  
+
V
O
TL072  
R
R
1
2
10KΩ  
10KΩ  
+12V  
V
= {R /(R +R )} V (max)  
1 1 2 O  
UL  
10KΩ  
-12V  
RL = {R /(R +R )} V (min)  
L
1
1
2
O
Characteristics subject to change without notice. 20 of 24  
REV 1.1.3 4/3/01  
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X9269  
Application Circuits (continued)  
Attenuator  
Filter  
C
V
+
S
R
V
R
R
2
O
1
3
+
R
V
O
V
S
R
2
R
4
R = R = R = R = 10kΩ  
1
2
3
4
R
1
G
= 1 + R /R  
2 1  
V
= G V  
S
O
O
fc = 1/(2πRC)  
-1/2 G +1/2  
Inverting Amplifier  
Equivalent L-R Circuit  
R
R
2
1
V
S
R
2
C
1
+
V
+
S
V
O
R
R
1
3
Z
IN  
V
= G V  
S
O
G = - R /R  
2
1
Z
= R + s R (R + R ) C = R + s Leq  
2 2 1 3 1 2  
IN  
(R + R ) >> R  
1
3
2
Function Generator  
C
R
R
1
2
+
+
R
R
}
A
B
}
frequency R , R , C  
1
2
amplitude R , R  
A
B
Characteristics subject to change without notice. 21 of 24  
REV 1.1.3 4/3/01  
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X9269  
PACKAGING INFORMATION  
24-Ball BGA (X9269TA/X9269UA)  
a
a
l
j
m
k
4
3
2
1
1
2
3
4
A
B
C
D
E
F
A
B
C
D
E
F
b
b
f
Top View (Bump Side Down)  
Bottom View (Bump Side Up)  
Note: Drawing not to scale  
d
= Die Orientation mark  
c
e
Side View (Bump Side Down)  
Millimeters  
Inches  
Symbol  
Min  
2.810  
4.588  
0.635  
0.433  
0.202  
0.284  
24  
Nom.  
2.775  
4.553  
0.505  
0.395  
0.110  
0.180  
Max  
Nom  
Min  
Max  
Package Body Dimension X  
Package Body Dimension Y  
Package Height  
a
b
c
d
e
f
2.845  
4.623  
0.765  
0.471  
0.294  
0.388  
0.11063 0.10925 0.11201  
0.18063 0.17925 0.18201  
0.02500 0.01988 0.03012  
0.01705 0.01555 0.01854  
0.00795 0.00433 0.01157  
0.01118 0.00709 0.01528  
Package Body Thickness  
Ball Height  
Ball Diameter  
Total Ball Count  
g
h
i
Ball Count X Axis  
Ball Count Y Axis  
Pins Pitch X Axis  
4
6
j
0.5  
Pins Pitch Y Axis  
k
l
0.5  
Edge to Ball Center (Corner) Distance  
Along X  
0.655  
0.620  
1.009  
0.690  
1.079  
0.02579 0.02441 0.02717  
0.04110 0.03972 0.04248  
Edge to Ball Center (Corner) Distance  
Along Y  
m
1.044  
Characteristics subject to change without notice. 22 of 24  
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X9269  
PACKAGING INFORMATION  
24-Lead Plastic Small Outline Gull Wing Package Type S  
0.393 (10.00)  
0.290 (7.37)  
0.299 (7.60)  
0.420 (10.65)  
Pin 1 Index  
Pin 1  
0.014 (0.35)  
0.020 (0.50)  
0.598 (15.20)  
0.610 (15.49)  
(4X) 7°  
0.092 (2.35)  
0.105 (2.65)  
0.003 (0.10)  
0.012 (0.30)  
0.050 (1.27)  
0.050"Typical  
0.010 (0.25)  
0.020 (0.50)  
X 45°  
0.050"  
Typical  
0° – 8°  
0.009 (0.22)  
0.013 (0.33)  
0.420"  
0.015 (0.40)  
0.050 (1.27)  
0.030" Typical  
24 Places  
FOOTPRINT  
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)  
Characteristics subject to change without notice. 23 of 24  
REV 1.1.3 4/3/01  
www.xicor.com  
X9269  
ORDERING INFORMATION  
X9269  
Y
P
T
V
V
Limits  
CC  
Device  
Blank = 5V 10%  
–2.7 = 2.7 to 5.5V  
Temperature Range  
Blank = Commercial = 0°C to +70°C  
I = Industrial = –40°C to +85°C  
Package  
S24 = 24-Lead SOIC  
xxx = xxx-Lead XBGA  
Potentiometer Organization  
Pot  
U =  
T =  
50KΩ  
100KΩ  
PART MARK CONVENTION  
xx Lead XBGA  
X9269xxxx-2.7  
X9269xxxx xx  
X9269 xxxx  
Top Mark  
X9269xxxxx I-2.7  
X9269xxxx-2.7  
X9269xxxx xx  
X9269 xxxx  
X9269xxxxx I-2.7  
LIMITED WARRANTY  
©Xicor, Inc. 2001 Patents Pending  
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.  
COPYRIGHTS ANDTRADEMARKS  
Xicor, Inc., the Xicor logo, E2POT, XDCP, XBGA, AUTOSTORE, Direct Write cell, Concurrent Read-Write, PASS, MPS, PushPOT, Block Lock, IdentiPROM,  
E2KEY, X24C16, SecureFlash, and SerialFlash are all trademarks or registered trademarks of Xicor, Inc. All other brand and product names mentioned herein are  
used for identification purposes only, and are trademarks or registered trademarks of their respective holders.  
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.  
Characteristics subject to change without notice. 24 of 24  
REV 1.1.3 4/3/01  
www.xicor.com  

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