Mixed Signal with 2-Wire Interface
X9448
Dual Digitally Controlled Potentiometer (XDCP™) & Voltage Comparator
FEATURES
DESCRIPTION
• Two digitally controlled potentiometers and two
voltage comparators in one package
• 2-wire serial interface
• Register oriented format
—Direct read/write wiper position
—Store as many as four positions per pot
• Fast response comparator
• Enable, latch, or shutdown comparator outputs
through ACR
• Auto-recall of WCR and ACR data from R0
• Hardware write protection, WP
• Separate analog and digital/system supplies
• Direct write cell
—Endurance–100,000 data changes per bit per
register
—Register data retention–100 years
• 16-bytes of EEPROM memory
• Power saving feature and low noise
• Two 10KΩ or two 2.5KΩ potentiometers
• Resolution: 64 taps each pot
• 24-lead TSSOP and 24-lead SOIC packages
The X9448 integrates two nonvolatile digitally controlled potentiometers (XDCP) and two voltage comparators on a CMOS monolithic microcircuit.
The X9448 contains two resistor arrays, each composed of 63 resistive elements. Between each element
and at either end are tap points accessible to the wiper
elements. The position of the wiper element on the
array is controlled by the user through the two wire
serial bus interface.
Each potentiometer has an associated voltage comparator. The comparator compares the external input
voltage VNI with the wiper voltage VW and sets the output voltage level to a logic high or low.
Each resistor array and comparator has associated
with it a wiper counter register (WCR), analog control
register (ACR), and eight 6-bit data registers that can
be directly written and read by the user. The contents
of the wiper counter register controls the position of
the wiper on the resistor array. The contents of the
analog control register controls the comparator and its
output. The potentiometer is programmed with a
2-wire serial interface
BLOCK DIAGRAM
VH (0,1)
(R0-R3)0,1
WCR0,1
WP
VL (0,1)
VW (0,1)
SCL
A0
A1
Interface
and
Control
A2
Circuitry
SDA
VNI (0,1)
A3
+
(R0-R3)0,1
ACR0,1
–
VOUT (0,1)
XDCP is a trademark of Xicor, Inc.
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Characteristics subject to change without notice.
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X9448
PIN DESCRIPTIONS
Hardware Write Protect Input WP
The WP pin when low prevents nonvolatile writes to the
wiper counter and analog control registers.
Host Interface Pins
Serial Clock (SCL)
The SCL input is used to clock data into and out of the
X9448.
Analog Supplies V+, V-
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 values, refer to
the guidelines for calculating typical values on the bus
pull-up resistors graph.
System Supply VCC and Ground VSS
The system supply VCC and its reference VSS is used
to bias the interface and control circuits.
The analog supplies V+, V- are the supply voltages for
the XDCP analog section and the voltage comparators.
PIN CONFIGURATION
SOIC
VCC
1
24
V+
Device Address (A0–A3)
VL0
2
23
VOUT0
The address inputs are used to set the least significant
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 X9448. A maximum of 16 devices may share the
same 2-wire serial bus.
VH0
3
22
VNI0
VW0
4
21
NC
A2
5
20
A0
WP
6
19
NC
SDA
7
18
A3
A1
8
17
SCL
VL1
9
16
NC
VH1
10
15
VNI1
VW1
11
14
VOUT1
VSS
12
13
V-
Potentiometer Pins
VH (VH0–VH1), VL (VL0–VL1)
The VH and VL inputs are equivalent to the terminal
connections on either end of a mechanical potentiometer.
VW (VW0–VW1)
The wiper output is equivalent to the wiper output of a
mechanical potentiometer and is connected to the
inverting input of the voltage comparator.
Comparator and Device Pins
Voltage Input VNI0, VNI1
VNI0 and VNI1 are the input voltages to the plus (noninverting) inputs of the two comparators.
Buffered Voltage Outputs VOUT0, VOUT1
The VOUT0, and VOUT1 are the buffered voltage
comparator outputs enabled by respective bits in the
volatile analog control register.
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X9448
TSSOP
SDA
A1
1
24
WP
2
23
A2
VL1
3
22
VW0
VH1
4
21
VH0
VW1
5
20
VL0
VSS
6
19
VCC
NC
7
18
NC
V-
8
17
V+
VOUT1
9
16
VOUT0
VNI1
10
15
VNI0
SCL
11
14
A0
A3
12
13
NC
X9448
Characteristics subject to change without notice.
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X9448
PIN NAMES
Symbol
Description
SCL
Serial Clock
SDA
Serial Data
A0-A3
Device Address
VH0–VH1,
VL0–VL1
Potentiometers (terminal equivalent)
VW0–VW1
Potentiometers (wiper equivalent)
VNI0, VNI1
Comparator Input Voltages
VOUT0, VOUT1
Buffered Comparator Outputs
WP
Hardware Write Protection
V+,V-
Analog and Voltage Comparator
Supplies
VCC
System/Digital Supply Voltage
VSS
System Ground
NC
No Connection
PRINCIPLES OF OPERATION
The X9448 is a highly integrated microcircuit incorporating two resistor arrays, two voltage comparators
and their associated registers and counters; and the
serial interface logic providing direct communication
between the host and the digitally-controlled potentiometers and voltage comparators.
Serial Interface
The X9448 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 X9448 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 (tLOW). SDA state changes during
SCL HIGH are reserved for indicating start and stop
conditions.
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Start Condition
All commands to the X9448 are preceded by the start
condition, which is a HIGH to LOW transition of SDA
while SCL is HIGH (tHIGH). The X9448 continuously
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 condition, which is a LOW to HIGH transition of SDA while
SCL is HIGH.
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.
The X9448 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 X9448 will respond with a final acknowledge.
Array Description
The X9448 is comprised of two resistor arrays and two
voltage comparators. 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 (VH and VL
inputs).
At both ends of each array and between each resistor
segment is a CMOS switch connected to the wiper
(VW) output. Within each individual array only one
switch may be turned on at a time. These switches are
controlled by a volatile wiper counter register (WCR).
The six 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.
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Characteristics subject to change without notice.
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X9448
Voltage Comparator
The comparator compares the wiper voltage VW with
the external input voltage VNI. The comparator and its
logic level output are controlled by the Shutdown,
Latch, and Enable bits of the analog control register
(ACR). Enable connects the comparator output to the
VOUT pin, Latch memorizes the output logic state, and
Shutdown removes the analog section supply voltages
to save power. The analog control register is programmed using the two wire serial interface.
write cycle. ACK polling (Flow 1) can be initiated
immediately. This involves issuing the start condition
followed by the device slave address. If the X9448 is
still busy with the write operation no ACK will be
returned. If the X9448 has completed the write operation an ACK will be returned and the master can then
proceed with the next operation.
Flow 1. ACK Polling Sequence
Nonvolatile Write
Command Completed
Enter ACK Polling
The ACR may be written directly, or it can be changed
by transferring the contents of one of four associated
data registers into the ACR. These data registers and
the ACR may be read and written by the host system.
Issue
START
INSTRUCTIONS AND PROGRAMMING
Issue Slave
Address
Device Addressing
Following a start condition the master must output the
address of the slave it is accessing. The most significant four bits of the slave address are the device type
identifier (refer to Figure 1 below). For the X9448 this
is fixed as 0101[B].
ACK
Returned?
0
1
A3
A2
A1
NO
Further
Operation
YES
Device Type
Identifier
1
NO
YES
Figure 1. Address/Identification Byte Format
0
Issue STOP
A0
Issue
Instruction
Issue STOP
PROCEED
PROCEED
Device 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 X9448 compares the
serial data stream with the address input state; a successful compare of all four address bits is required for
the X9448 to respond with an acknowledge. The A0–
A3 inputs can be actively driven by CMOS input signals or tied to VCC or VSS.
Instruction Structure
The byte following the address contains the instruction
and register pointer information. The four most significant bits are the instruction. The next four bits point to
one of two pots or one of two voltage comparators and
when applicable they point to one of four associated
registers. The format is shown below in Figure 2.
Figure 2. Instruction Byte Format
Acknowledge Polling
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 X9448 initiates the internal
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Register
Select
I3
I2
I1
Instructions
I0
R1
R0
P1
P0
WCR and ACR Select
Characteristics subject to change without notice.
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X9448
Four instructions require a three-byte sequence to
complete. The basic sequence is illustrated in Figure 4.
These instructions transfer data between the host and
the X9448; either between the host and one of the data
registers or directly between the host and the wiper
counter and analog control registers. These instructions are: read wiper counter register or analog control
register, read the current wiper position of the selected
pot or the comparator control bits, Write wiper counter
register or analog control register, i.e. change current
wiper position of the selected pot or control the voltage
comparator; read data register, read the contents of the
selected nonvolatile register; write data register, write a
new value to the selected data register. The bit structures of the instructions are shown in Figure 6.
The four high order bits define the instruction. The next
two bits (R1 and R0) select one of the four registers
that is to be acted upon when a register oriented
instruction is issued. The last two bits (P1 and P0)
select which one of the two potentiometers or which
one of the two voltage comparators is to be affected by
the instruction.
Four of the nine instructions end with the transmission
of the instruction byte. The basic sequence is illustrated in Figure 3. These two-byte instructions
exchange data between the wiper counter register or
analog control register and one of the data registers. A
transfer from a data register to a wiper counter register
or analog control register is essentially a write to a
static RAM. The response of the wiper to this action
will be delayed tSTPWV. A transfer from the Wiper
Counter Register current wiper position to a data register is a write to nonvolatile memory and takes a minimum of tWR to complete. The transfer can occur
between one of the two potentiometers or one of the
two voltage comparators and one of its associated registers; or it may occur globally, wherein the transfer
occurs between both of the potentiometers and voltage
comparators and one of their associated registers.
The increment/decrement command is different from
the other commands. Once the command is issued
and the X9448 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
(tHIGH) while SDA is HIGH, the selected wiper will
move one resistor segment towards the VH terminal.
Similarly, for each SCL clock pulse while SDA is LOW,
the selected wiper will move one resistor segment
towards the VL terminal. A detailed illustration of the
sequence for this operation is shown in Figure 5.
Figure 3. Two-Byte Command Sequence
SCL
SDA
S
T
A
R
T
0
1
0
1
A3
A2
A1
A0
A
C
K
I3
I2
I1
I0
R1 R0 P1 P0
A
C
K
S
T
O
P
Figure 4. Three-Byte Command Sequence
SCL
SDA
S
T
A
R
T
0
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1
0
1
A3 A2 A1 A0 A
C
K
I3
I2
I1 I0
P1 P0 R1 R0 A
C
K
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D5 D4 D3 D2 D1 D0
Characteristics subject to change without notice.
A
C
K
S
T
O
P
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X9448
Figure 5. Increment/Decrement Command Sequence
SCL
SDA
X
S
T
A
R
T
0
1
0
1
A3 A2 A1 A0
A
C
K
I3
I2
I1
I0
X
P1 P0 R1 R0 A
C
K
I
N
C
1
I
N
C
2
I
N
C
n
D
E
C
1
D
E
C
n
S
T
O
P
INSTRUCTION SET
Read Wiper Counter Register (WCR) or Analog Control Register (ACR)
Read the contents of the Wiper Counter Register or Analog Control Register pointed to by P1-P0.
S device type
device
T
identifier
addresses
A
R 0 1 0 1 A A A A
3 2 1 0
T
instruction WCR/ACR
S
opcode
addresses
A
C
P P
K 1 0 0 1 0 0 1 0
register data
S
(sent by slave on SDA)
A
C
D D D D D D
K 0 0 5 4 3 2 1 0
M
A
C
K
S
T
O
P
P1 P0: 00-WCR0, 01 - WCR1
P1 P0: 10-ACR0, 11 - ACR1
Write Wiper Counter Register (WCR) or Analog Control Register (ACR)
Write new value to the Wiper Counter Register or Analog Control Register pointed to by P1-P0.
device
S device type
identifier
addresses
T
A
R 0 1 0 1 A A A A
3 2 1 0
T
instruction WCR/ACR
S
opcode
addresses
A
C
P P
K 1 0 1 0 0 0 1 0
register data
S
(sent by master on SDA)
A
C
D D D D D D
K 0 0 5 4 3 2 1 0
S
A
C
K
S
T
O
P
P1 P0: 00-WCR0, 01 - WCR1
P1 P0: 10-ACR0, 11 - ACR1
Read Data Register (DR)
Read the contents of the Register pointed to by P1-P0 and R1-R0.
S device type
device
instruction WCR/ACR/DR
register data
S
S
T identifier
addresses
opcode
addresses
(sent by master on SDA)
A
A
A
C
C
A
A
A
A
R
R
P
P
D D D D D D
R 0 1 0 1
1 0 1 1
0 0
3 2 1 0 K
1 0 1 0 K
5 4 3 2 1 0
T
M
A
C
K
S
T
O
P
R1 R0: 00-R0, 10-R1
01-R2, 11-R3
Definitions:
SACK – Slave acknowledge, MACK – Master acknowledge, I/O – Increment/Decrement (I/O), R – Register,
P – Potentiometer
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Characteristics subject to change without notice.
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X9448
Write Data Register (DR)
Write new value to the Register pointed to by P1-P0 and R1-R0.
S device type
device
instruction WCR/ACR/DR
register data
S
S
T identifier
addresses
opcode
addresses
(sent by master on SDA)
A
A
A
C
C
R R P P
D D D D D D
R 0 1 0 1 A A A A
1 1 0 0
0 0
3 2 1 0 K
1 0 1 0 K
5 4 3 2 1 0
T
S
A
C
K
S
T
O
P
HIGH-VOLTAGE
WRITE CYCLE
Transfer Data Register to Wiper Counter Register or Analog Control Register
Transfer the contents of the Register pointed to by R1-R0 to the WCR or ACR pointed to by P1-P0.
S device type
device
T identifier
addresses
A
R 0 1 0 1 A A A A
3 2 1 0
T
instruction WCR/ACR/DR
S
S S
opcode
addresses
A
A T
C
R R P P C O
K 1 1 0 1 1 0 1 0 K P
Transfer Wiper Counter or Analog Control Register to Data Register
Transfer the contents of the WCR or ACR pointed to by P1-P0 to the Register pointed to by R1-R0.
device
S device type
T
identifier
addresses
A
R 0 1 0 1 A A A A
3 2 1 0
T
instruction WCR/ACR/DR
S S
S
opcode
addresses
A T
A
C
R R P P C O
1 1 1 0
K
1 0 1 0 K P
HIGH-VOLTAGE
WRITE CYCLE
Global Transfer Data Register to Wiper Counter or Analog Control Register
Transfer the contents of all four Data Registers pointed to by R1-R0 to their respective WCR or ACR.
device
S device type
T
identifier
addresses
A
R 0 1 0 1 A A A A
3 2 1 0
T
instruction
DR
S
opcode
addresses
A
C
R R
K 0 0 0 1 1 0 0 0
S
A
C
K
S
T
O
P
Global Transfer Wiper Counter or Analog Control Register to Data Register
Transfer the contents of all WCRs and ACRs to their respective data Registers pointed to by R1-R0.
S device type
device
addresses
T identifier
A
R 0 1 0 1 A A A A
3 2 1 0
T
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instruction
DR
S
opcode
addresses
A
C
R R
1 0 0 0
0 0
K
1 0
S
A
C
K
S
T
O
P
HIGH-VOLTAGE
WRITE CYCLE
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Characteristics subject to change without notice.
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X9448
Increment/Decrement Wiper Counter Register
Enable Increment/decrement of the WCR pointed to by P1-P0.
S device type
device
T
identifier
addresses
A
R 0 1 0 1 A A A A
3 2 1 0
T
instruction
WCR
S
opcode
addresses
A
C
P P
K 0 0 1 0 0 0 1 0
increment/decrement
S
(sent by master on SDA)
A
C I/ I/
I/ I/
K D D . . . . D D
S
T
O
P
P1 P0: 00 or 01 only.
REGISTERS OPERATION
Both XDCP potentiometers and voltage comparators
share the serial interface and share a common architecture. Each potentiometer and voltage comparator is
associated with wiper counter and analog control registers and eight data registers. A detailed discussion of
the register organization and array operation follows.
Wiper Counter (WCR) and Analog Control
Registers (ACR)
The X9448 contains two wiper counter registers one
for each XDCP potentiometer and two analog control
registers, one for each of the two voltage comparators.
The wiper counter register is equivalent to a serial-in,
parallel-out counter with its outputs decoded to select
one of sixty-four switches along its resistor array. The
contents of the wiper counter register and analog control register 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
(DR) via the XFR data register instruction (parallel
load); it can be modified one step at a time by the
increment/decrement instruction (WCR only). Finally, it
is loaded with the contents of its data register zero (R0)
upon power-up.
Data Registers (DR)
Each potentiometer and each voltage comparator has
four nonvolatile data registers (DR). 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 or ACR. It should be noted all operations changing data in one of these registers is a nonvolatile operation and will take a maximum of 10ms.
If the application does not require storage of multiple
settings for the potentiometer or comparator, these registers can be used as regular memory locations that
could store system parameters or user preference data.
REGISTER DESCRIPTIONS
Wiper Counter Register (WCR)
0
0
WP5 WP4 WP3 WP2 WP1
(volatile)
Programming the ACR is similar to the WCR. However,
the 6 bits in the WCR positions the wiper in the resistor
array while 3 bits in the ACR control the comparator
and its output.
Analog Control Register (ACR)
0
0
User User User
Shut-bit5 -bit4 -bit3 Latch Enable down
(LSB)
Shutdown
“1”
indicates power is connected to the voltage
comparator.
“0”
indicates power is not connected to the voltage
comparator.
Enable
“1”
indicates the output buffer of the voltage comparator is enabled.
“0”
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(LSB)
WP0-WP5 identify wiper position.
(volatile)
The wiper counter and analog control register are volatile registers; that is, their contents are lost when the
X9448 is powered-down. Although the registers are
automatically loaded with the value in R0 upon powerup, it should be noted this may be different from the
value present at power-down.
WP0
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indicates the output buffer of the voltage comparator is disabled.
Characteristics subject to change without notice.
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X9448
Latch
“1”
indicates the output of the voltage comparator
is memorized or latched.
“0”
indicates the output of the voltage comparator
is not latched.
Userbits—available for user applications
Memory Map
WCRO
WCR1
ACR0
ACR1
R0
R0
R0
R0
R1
R1
R1
R1
R2
R2
R2
R2
R3
R3
R3
R3
Data Registers (DR, R0-R3)
Wiper Position or Analog Control Data or User Data
(Nonvolatile)
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Characteristics subject to change without notice.
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X9448
ABSOLUTE MAXIMUM RATINGS
COMMENT
Temperature under bias ....................–65°C to +135°C
Storage temperature .........................–65°C to +150°C
Voltage on SDA, SCL or any
address input with respect to VSS ........... –1V to +7V
Voltage on any V+ (referenced to VSS ................... +7V
Voltage on any V- (referenced to VSS .................... -7V
(V+) – (V-) ....................................................................10V
Any VH .................................................................... V+
Any VL ...................................................................... VLead temperature (soldering, 10 seconds) ........300°C
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
listed in the operational sections of this specification) is
not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
Max.
Device
Supply Voltage (VCC) Limits
+70°C
X9448
5V ±10%
Industrial
Min.
0°C
–40°C
+85°C
X9448-2.7
2.7V to 5.5V
Military
–55°C
+125°C
Temperature
Commercial
POTENTIOMETER CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.)
Limits
Symbol
RTOTAL
Parameter
Min.
End to end resistance
Typ.
Max.
Unit
+20
%
50
mW
+3
mA
40
100
Ω
VCC = 5V, Wiper Current = 3mA
100
250
Ω
VCC = 2.7-5V, Wiper Current = 3mA
V
–20
Power rating
IW
Wiper current
RW
Wiper resistance
–3
Vv+
Voltage on V+ Pin
X9440
+4.5
+5.5
X9440-2.7
+2.7
+5.5
Vv-
Voltage on V- Pin
X9440
-5.5
-4.5
X9440-2.7
-5.5
-2.7
V-
V+
VTERM
Voltage on any VH or VL pin
Noise
Resolution
(4)
Absolute linearity
Relative
(1)
linearity (2)
Temperature Coefficient of RTOTAL
V
dBv
1.6
%
–0.2
25°C, each pot
V
-120
–1
Test Conditions
Ref: 1V
+1
MI(3)
Vw(n)(actual)–Vw(n)(expected)
+0.2
MI(3)
Vw(n + 1)–[Vw(n) + MI]
±300
ppm/°C
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/63 or (VH–VL)/63, single pot
(4) Individual array resolutions
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X9448
COMPARATOR ELECTRICAL CHARACTERISTICS
(Over the recommended operating conditions unless otherwise specified.)
Limits
Symbol
Parameter
VOS
Min.
Input offset voltage
Typ.
-1
-5
Input current
IB
tR
Response time
IO
Output current
AV
Voltage gain
PSRR
V-
mV
mV
-1
Test Conditions
V+/V- = ±3V
V+/V- = ±5V
pA
200
V
ns
1
note 1
mA
V/mV
60
Output voltage range
VOR
1
5
V+
Power supply rejection ratio
TCVOS
Unit
10
Input voltage range
VIR
Max.
VSS
dB
VCC
Input offset voltage drift
V
6
µV/°C
IS
Supply current (V+ to V-)
1.2
.5
mA
mA
V+/V- = ±5V
V+/V- = ±3V
TON
Comparator enable time
1
µs
note 2
VOL
Output low voltage
V
IO = 1mA
VOH
Output high voltage
V
IO = 1mA
0.4
VCC – 0.8
Notes: (1) 100mV step with 100mV overdrive, ZL = 10KΩ || 15pF, 10-90% risetime
(2) Time from leading edge of enable bit to valid VOUT.
SYSTEM/DIGITAL D.C. OPERATING CHARACTERISTICS
(Over the recommended operating conditions unless otherwise specified.)
Limits
Symbol
Parameter
ICC
VCC supply current (active)
ISB
Min.
Typ.
Max.
Unit
400
µA
fSCL = 400kHz, SDA = Open,
Other Inputs = VSS
Test Conditions
VCC current (standby)
1
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
VCC x 0.7
VCC + 0.5
V
VIL
Input LOW voltage
–0.5
VCC x 0.1
V
VOL
Output LOW voltage
0.4
V
IOL = 3mA
ENDURANCE AND DATA RETENTION
Parameter
Min.
Unit
Minimum endurance
100,000
Data changes per bit per register
Data retention
100
Years
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X9448
CAPACITANCE
Symbol
Test
Typical
Unit
Test Conditions
CI/O
Input/output capacitance (SDA)
8
pF
VI/O = 0V
CIN
Input capacitance (A0, A1, A2, A3, and SCL)
6
pF
VIN = 0V
10/10/25
pF
CL, CH, CW
Potentiometer capacitance
Power-Up Timing and Sequence
Power up sequence(1): (1) VCC
{V+ ≤ VCC at all times}
(2) V+ and V–
Power down sequence: no limitation
A.C. TEST CONDITIONS
EQUIVALENT A.C. LOAD CIRCUIT
Input pulse levels
VCC x 0.1 to VCC x 0.9
Input rise and fall times
10ns
Input and output timing level
VCC x 0.5
Note:
5V
2.7V
1533Ω
(1) Applicable to recall and power consumption applications
SD Output
100pF
100pF
TIMING DIAGRAMS
START and STOP Timing
g
(START)
(STOP)
tF
tR
SCL
tSU:STA
tHD:STA
tSU:STO
tR
tF
SDA
Input Timing
tCYC
tHIGH
SCL
tLOW
SDA
tSU:DAT
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tBUF
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X9448
Output Timing
SCL
SDA
tDH
tAA
XDCP Timing (for All Load Instructions)
(STOP)
SCL
LSB
SDA
tWRL
VWx
XDCP Timing (for Increment/Decrement Instruction)
SCL
SDA
Wiper Register Address
Inc/Dec
Inc/Dec
tWRID
VWx
Write Protect and Device Address Pins Timing
(START)
(STOP)
SCL
...
(Any Instruction)
...
SDA
...
tSU:WPA
tHD:WPA
WP
A0, A1
A2, A3
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X9448
AC Timing
Symbol
Parameter
fSCL
Clock frequency
tCYC
Clock cycle time
tHIGH
tLOW
Min.
Max.
Unit
400
kHz
2500
ns
Clock high time
600
ns
Clock low time
1300
ns
tSU:STA
Start setup time
600
ns
tHD:STA
Start hold time
600
ns
tSU:STO
Stop setup time
600
ns
tSU:DAT
SDA data input setup time
100
ns
SDA data input hold time
0/30
ns
(4)
tHD:DAT
tR
SCL and SDA rise time
tF
SCL and SDA fall time
300
ns
300
ns
900
ns
tAA
SCL low to SDA data output valid time
100
tDH
SDA Data output hold time
50
ns
Noise suppression time constant at SCL and SDA inputs
50
ns
1300
ns
TI
tBUF
Bus free time (prior to any transmission)
tSU:WPA
WP, A0, A1, A2 and A3 setup time
0
ns
tHD:WPA
WP, A0, A1, A2 and A3 hold time
0
ns
High-Voltage Write Cycle Timing
Symbol
Parameter
Typ.
Max.
Unit
tWR
High-voltage write cycle time (store instructions)
5
10
ms
Symbol
Parameter
Min.
Max.
Unit
tWRL
Wiper response time after instruction issued (all load instructions)
10
µs
XDCP Timing
Note:
(4) VCC = 5V/2.7V
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X9448
BASIC APPLICATIONS
Programmable Level Detector with Memory (typical bias conditions)
VREF1 (+5V)
+5V
SCL
SCL VCC
SDA
SDA
(+5V)
VH
V+
VW
–
VOUT
VOUT
+
9448
VSS
VL
VNI
V–
(–5V)
+
VREF2 (–5V)
VT>VW, VOUT = High
VT<VW, VOUT = Low
VTRANSDUCER (VT)
–
Programmable Window Detector with Memory
+5V
VOUT0
9448
+
SCL
VW0
SDA
VOUT0
–
VOUT0 = L
VOUT1 = L
VOUT0 = L
VOUT1 = H
VOUT0 = H
VOUT1 = H
+
VOUT1
–
VW1
–5V
VS
VLL
(VW1)
VUL
(VW0)
+
VS
–
For the signal voltage
VS > the upper limit VUL, (VOUT0 = H) • (VOUT1 = H)
VS < the lower limit VLL, (VOUT0 = L) • (VOUT1 = L)
For the window VLL ≤ VS ≤ VUL, (VOUT0 = L) • (VOUT1 = H)
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X9448
BASIC APPLICATION (continued)
Programmable Oscillator with Memory
+5V
VH
SCL
SDA
9448
R
–
V+
VOUT
+
V–
VL VW
R2
C
+5V
R3
R1
Frequency µ R, C
Duty Cycle µ R1, R2, R3
Programmable Schmitt Trigger with Memory
VR
VH
VW
R
9448
–
V+
VOUT
+
VOUT
V–
VL
VS
VS
R1
V UL
R2
VLL
VUL
R1 + R2
R1
= ------------------- V W – ------ V OUT ( min )
R2
R2
R1 + R2
R1
V LL = ------------------- V W – ------ V OUT ( max )
R2
R2
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X9448
BASIC APPLICATION (continued)
Programmable Level Detector (alternate technique)
+
VS
VOUT
R1 {
–
R2 {
VOUT
+
VCC
VS
-R1
V
R2 R
+
VR
VSS
R1
V OUT = High for V S < – ------ V R
R2
R1
V OUT = Low for V S > – ------ V R
R2
R 1 + R 2 = R POT
Programmable Time Delay with Memory
+5V
VH
VOUT
VW
+5v
–
VS
VOUT
+
t
VW
VNI
VL
+5v
t
VNI
+5v
VOUT
VS
t
Dt
R
C
5V
∆t = RC ln ----------------------
5V – V W
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X9448
PACKAGING INFORMATION
24-Lead Plastic Small Outline Gull Wing Package Type S
0.290 (7.37) 0.393 (10.00)
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)
X 45°
0.020 (0.50)
0.050"
Typical
0° – 8°
0.009 (0.22)
0.013 (0.33)
0.420"
0.015 (0.40)
0.050 (1.27)
FOOTPRINT
0.030" Typical
24 Places
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
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X9448
PACKAGING INFORMATION
24-Lead Plastic, TSSOP Package Type V
.026 (.65) BSC
.169 (4.3)
.252 (6.4) BSC
.177 (4.5)
.303 (7.70)
.311 (7.90)
.047 (1.20)
.0075 (.19)
.0118 (.30)
.002 (.06)
.005 (.15)
.010 (.25)
Gage Plane
0°–8°
(4.16) (7.72)
Seating Plane
.020 (.50)
.030 (.75)
(1.78)
Detail A (20X)
(0.42)
(0.65)
.031 (.80)
.041 (1.05)
ALL MEASUREMENTS ARE TYPICAL
See Detail “A”
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
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X9448
ORDERING INFORMATION
X9448
Y
P
T
V
VCC Limits
Blank = 5V ±10%
–2.7 = 2.7 to 5.5V
Device
Temperature Range
Blank = Commercial = 0°C to +70°C
I = Industrial = –40°C to +85°C
Package
P24 = 24-Lead Plastic DIP
S24 = 24-Lead SOIC
V24 = 24-Lead TSSOP
Potentiometer Organization
Pot 0 Pot 1
W=
10KΩ 10KΩ
Y=
2.5KΩ 2.5KΩ
LIMITED WARRANTY
©Xicor, Inc. 2000 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.
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.
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20 of 20