X9400
®
Low Noise/Low Power/SPI Bus
Data Sheet
March 31, 2005
Quad Digitally Controlled Potentiometers
(XDCP™)
FN8189.1
DESCRIPTION
The X9400 integrates four digitally controlled
potentiometers (XDCPs) on a monolithic CMOS
integrated circuit.
FEATURES
• Four potentiometers per package
• 64 resistor taps
• SPI serial interface for write, read, and transfer
operations of the potentiometer
• Wiper resistance, 40Ω typical at 5V.
• Four non-volatile data registers for each
potentiometer
• Non-volatile storage of multiple wiper position
• Power-on recall. Loads saved wiper position on
power-up.
• Standby current < 1µA max
• System VCC: 2.7V to 5.5V operation
• Analog V+/V–: -5V to +5V
• 10kΩ, 2.5kΩ End to end resistance
• 100 yr. data retention
• Endurance: 100,000 data changes per bit per
register
• Low power CMOS
• 24-lead SOIC and 24-lead TSSOP
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 SPI
serial bus interface. Each potentiometer has
associated with it a volatile Wiper Counter Register
(WCR) and four nonvolatile Data Registers (DR0-3)
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 contents of DR0 to the WCR.
The XDCP can be used as a three-terminal
potentiometer or as a two-terminal variable resistor in
a wide variety of applications including control,
parameter adjustments, and signal processing.
BLOCK DIAGRAM
VCC
Pot 0
VSS
V+
V-
R0 R1
HOLD
R2 R3
CS
SCK
SO
SI
A0
A1
Interface
and
Control
Circuitry
VH0/RH0
Wiper
Counter
Register
(WCR)
VL0/RL0
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
Resistor
Array
Pot 2
VH2/RH2
VL2/RL2
VW0/RW0
VW2/RW2
VW1/RW1
VW3/RW3
8
Data
WP
R0 R1
R2 R3
1
Wiper
Counter
Register
(WCR)
Resistor
Array
Pot 1
VH1/RH1
VL1/RL1
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
Resistor
Array
Pot 3
VH3/RH3
VL3/RL3
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-352-6832 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
XDCP is a trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2005. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
X9400
PIN DESCRIPTIONS
be brought LOW while SCK is LOW. To resume
communication, HOLD is brought HIGH, again while
SCK is LOW. If the pause feature is not used, HOLD
should be held HIGH at all times.
Host Interface Pins
Serial Output (SO)
SO is a push/pull serial data output pin. During a read
cycle, data is shifted out on this pin. Data is clocked
out by the falling edge of the serial clock.
Serial Input
SI is the serial data input pin. All opcodes, byte
addresses and data to be written to the pots and pot
registers are input on this pin. Data is latched by the
rising edge of the serial clock.
Serial Clock (SCK)
The SCK input is used to clock data into and out of the
X9400.
Chip Select (CS)
When CS is HIGH, the X9400 is deselected and the
SO pin is at high impedance, and (unless an internal
write cycle is underway) the device will be in the
standby state. CS LOW enables the X9400, placing it
in the active power mode. It should be noted that after
a power-up, a HIGH to LOW transition on CS is
required prior to the start of any operation.
Hold (HOLD)
HOLD is used in conjunction with the CS pin to select
the device. Once the part is selected and a serial
sequence is underway, HOLD may be used to pause
the serial communication with the controller without
resetting the serial sequence. To pause, HOLD must
Device Address (A0 - A1)
The address inputs are used to set the least significant
2 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 X9400. A maximum of 4 devices may occupy the
SPI serial bus.
Potentiometer Pins
VH/RH (VH0/RH0 - VH3/RH3), VL/RL (VL0/RL0 VL3/RL3)
The VH/RH and VL/RL inputs are equivalent to the
terminal connections on either end of a mechanical
potentiometer.
VW/RW (VW0/RW0 - VW3/RW3)
The wiper outputs are equivalent to the wiper output of
a mechanical potentiometer.
Hardware Write Protect Input (WP)
The WP pin when LOW prevents nonvolatile writes to
the Data Registers.
Analog Supplies (V+, V-)
The analog Supplies V+, V- are the supply voltages for
the XDCP analog section.
PIN CONFIGURATION
SOIC
TSSOP
VCC
1
24
V+
SI
VL0/RL0
2
23
VL3/RL3
A1
VH0/RH0
3
22
VH3/RH3
VW0/RW0
4
21
VW3/RW3
VL1/RL1
VH1/RH1
CS
5
20
A0
VW1/RW1
19
SO
VSS
6
18
HOLD
V-
7
8
17
SCK
VW2/RW2
VL1/RL1
9
16
VL2/RL2
VH1/RH1
10
15
VH2/RH2
VW1/RW1
11
14
VW2/RW2
12
13
V-
WP
6
SI
7
A1
V
SS
X9400
2
24
WP
2
23
CS
3
22
VW0/RW0
4
21
VH0/RH0
5
20
VL0/RL0
19
VCC
18
V+
8
17
VL3/RL3
VH2/RH2
9
16
VH3/RH3
VL2/RL2
10
15
VW3/RW3
SCK
11
14
A0
HOLD
12
13
SO
1
X9400
FN8189.1
March 31, 2005
X9400
Wiper Counter Register (WCR)
PIN NAMES
Symbol
Description
SCK
Serial Clock
SI, SO
Serial Data
A0 - A1
Device Address
VH0/RH0 - VH3/RH3,
VL0/RL0 - VL3/RL3
Potentiometer Pins (terminal
equivalent)
VW0/RW0 - VW1/RW1
Potentiometer Pins (wiper
equivalent)
WP
Hardware Write Protection
VCC
System Supply Voltage
VSS
System Ground
NC
No Connection
DEVICE DESCRIPTION
The X9400 is a highly 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 XDCP potentiometers.
Serial Interface
The X9400 supports the SPI interface hardware
conventions. The device is accessed via the SI input
with data clocked in on the rising SCK. CS must be
LOW and the HOLD and WP pins must be HIGH
during the entire operation.
The SO and SI pins can be connected together, since
they have three state outputs. This can help to reduce
system pin count.
The X9400 contains four Wiper Counter Registers,
one for each XDCP potentiometer. The WCR is
equivalent to a serial-in, parallel-out register/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 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 or
global XFR data register instructions (parallel load); it
can be modified one step at a time by the
increment/decrement instruction. Finally, it is loaded
with the contents of its Data Register zero (DR0) upon
power-up.
The Wiper Counter Register is a volatile register; that
is, its contents are lost when the X9400 is powereddown. 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.
Data Registers
Each potentiometer has four 6-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.
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.
Array Description
The X9400 is comprised of four 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 (VH/RH and VL/RL inputs).
Data Register Detail
(MSB)
(LSB)
D5
D4
D3
D2
D1
D0
NV
NV
NV
NV
NV
NV
At both ends of each array and between each resistor
segment is a CMOS switch connected to the wiper
(VW/RW) output. Within each individual array only one
switch may be turned on at a time.
These switches are controlled by a wiper counter
register (WCR). The six bits of the WCR are decoded
to select, and enable, one of sixty-four switches.
3
FN8189.1
March 31, 2005
X9400
Figure 1. Detailed Potentiometer Block Diagram
(One of Four Arrays)
Serial Data Path
Serial
Bus
Input
From Interface
Circuitry
Register 0
6
Parallel
Bus
Input
Wiper
Counter
Register
(WCR)
Register 3
D
e
c
o
d
e
INC/DEC
Logic
If WCR = 00[H] then VW/RW = VL/RL
If WCR = 3F[H] then VW/RW = VH/RH
C
o
u
n
t
e
r
Register 1
8
Register 2
VH/RH
UP/DN
Modified SCL
UP/DN
VL/RL
CLK
VW/RW
Write in Process
The contents of the Data Registers are saved to
nonvolatile memory when the CS pin goes from LOW
to HIGH after a complete write sequence is received
by the device. The progress of this internal write
operation can be monitored by a write in process bit
(WIP). The WIP bit is read with a read status
command.
continue the command sequence. The A0 - A1 inputs can
be actively driven by CMOS input signals or tied to VCC
or VSS.
The remaining two bits in the slave byte must be set to 0.
Figure 2. Identification Byte Format
Device Type
Identifier
INSTRUCTIONS
0
Identification (ID) Byte
The first byte sent to the X9400 from the host,
following a CS going HIGH to LOW, is called the
Identification byte. The most significant four bits of the
slave address are a device type identifier, for the
X9400 this is fixed as 0101[B] (refer to Figure 2).
The two least significant bits in the ID byte select one
of four devices on the bus. The physical device
address is defined by the state of the A0 - A1 input
pins. The X9400 compares the serial data stream with
the address input state; a successful compare of both
address bits is required for the X9400 to successfully
4
1
0
1
0
0
A1
A0
Device Address
Instruction Byte
The next byte sent to the X9400 contains the
instruction and register pointer information. The four
most significant bits are the instruction. The next four
bits point to one of the four pots and, when applicable,
they point to one of four associated registers. The
format is shown below in Figure 3.
FN8189.1
March 31, 2005
X9400
Five instructions require a three-byte sequence to
complete. These instructions transfer data between the
host and the X9400; either between the host and one of
the data registers or directly between the host and the
Wiper Counter Register. These instructions are:
Figure 3. Instruction Byte Format
Register
Select
I3
I2
I1
I0
R1
R0
P1
P0
Pot Select
Instructions
The four high order bits of the instruction byte specify
the operation. 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) selects which one of the four
potentiometers is to be affected by the instruction.
Four of the ten instructions are two bytes in length and
end with the transmission of the instruction byte.
These instructions are:
– XFR Data Register to Wiper Counter Register—This
transfers the contents of one specified Data Register
to the associated Wiper Counter Register.
– XFR Wiper Counter Register to Data Register —
This transfers the contents of the specified Wiper
Counter Register to the specified associated Data
Register.
– Global XFR Data Register to Wiper Counter Register
—This transfers the contents of all specified Data
Registers to the associated Wiper Counter Registers.
– Global XFR Wiper Counter Register to Data Register
—This transfers the contents of all Wiper Counter
Registers to the specified associated Data Registers.
– Read Wiper Counter Register—read the current
wiper position of the selected pot,
– Write Wiper Counter Register—change current
wiper position of the selected pot,
– Read Data Register—read the contents of the
selected data register;
– Write Data Register—write a new value to the
selected data register.
– Read Status—This command returns the contents
of the WIP bit which indicates if the internal write
cycle is in progress.
The sequence of these operations is shown in Figure 5
and Figure 6.
The final command is Increment/Decrement. It is
different from the other commands, because it’s length
is indeterminate. Once the command is issued, the
master can clock the selected wiper up and/or down in
one resistor segment steps; thereby, providing a fine
tuning capability to the host. For each SCK clock pulse
(tHIGH) while SI is HIGH, the selected wiper will move
one resistor segment towards the VH/RH terminal.
Similarly, for each SCK clock pulse while SI is LOW, the
selected wiper will move one resistor segment towards
the VL/RL terminal. A detailed illustration of the
sequence and timing for this operation are shown in
Figure 7 and Figure 8.
The basic sequence of the two byte instructions is
illustrated in Figure 4. 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, with the static RAM
controlling the wiper position. The response of the
wiper to this action will be delayed by tWRL. A transfer
from the WCR (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 four potentiometers and one of its
associated registers; or it may occur globally, where the
transfer occurs between all potentiometers and one
associated register.
5
FN8189.1
March 31, 2005
X9400
Figure 4. Two-Byte Instruction Sequence
CS
SCK
SI
0
1
0
1
0
0
A1
A0
I3
I2
I1
I0
R1 R0
P1 P0
Figure 5. Three-Byte Instruction Sequence (Write)
CS
SCK
SI
0
1
0
0
1
0
A1 A0
I3
I2
I1 I0
R1 R0 P1 P0
0
0
D5 D4 D3 D2 D1 D0
Figure 6. Three-Byte Instruction Sequence (Read)
CS
SCK
SI
Don’t Care
0
1
0
0
1
0
A1 A0
I3
I2
I1 I0
R1 R0 P1 P0
S0
0
0
D5 D4 D3 D2 D1 D0
Figure 7. Increment/Decrement Instruction Sequence
CS
SCK
SI
0
1
0
1
0
6
0
A1 A0
I3
I2
I1
I0
0
0
P1
P0
I
N
C
1
I
N
C
2
I
N
C
n
D
E
C
1
D
E
C
n
FN8189.1
March 31, 2005
X9400
Figure 8. Increment/Decrement Timing Limits
tWRID
SCK
SI
Voltage Out
VW/RW
INC/DEC CMD Issued
Table 1. Instruction Set
Read Wiper Counter Register
I3
1
I2
0
Instruction Set
I1 I0 R1 R0 P1
0
1
0
0
P1
Write Wiper Counter Register
1
0
1
0
Read Data Register
1
0
1
1
R1 R0
P1
Write Data Register
1
1
0
0
R1 R0
P1
XFR Data Register to Wiper
Counter Register
1
1
0
1
R1 R0
P1
XFR Wiper Counter Register
to Data Register
1
1
1
0
R1 R0
P1
Global XFR Data Register to
Wiper Counter Register
0
0
0
1
R1 R0
0
Global XFR Wiper Counter
Register to Data Register
1
0
0
0
R1 R0
0
Increment/Decrement Wiper
Counter Register
Read Status (WIP bit)
0
0
1
0
0
0
P1
0
1
0
1
0
0
0
Instruction
7
0
0
P1
Operation
P0
P0 Read the contents of the Wiper Counter Register
pointed to by P1 - P0
P0 Write new value to the Wiper Counter Register
pointed to by P1 - P0
P0 Read the contents of the Data Register pointed to
by P1 - P0 and R1 - R0
P0 Write new value to the Data Register pointed to by
P1 - P0 and R1 - R0
P0 Transfer the contents of the Data Register pointed to
by R1 - R0 to the Wiper Counter Register pointed to by
P1 - P0
P0 Transfer the contents of the Wiper Counter
Register pointed to by P1 - P0 to the Register
pointed to by R1 - R0
0 Transfer the contents of the Data Registers pointed
to by R1 - R0 of all four pots to their respective Wiper
Counter Register
0 Transfer the contents of all Wiper Counter
Registers to their respective data Registers
pointed to by R1 - R0 of all four pots
P0 Enable Increment/decrement of the Wiper Counter
Register pointed to by P1 - P0
1 Read the status of the internal write cycle, by
checking the WIP bit.
FN8189.1
March 31, 2005
X9400
Instruction Format
Notes: (1)
(2)
(3)
(4)
“A1 ~ A0”: stands for the device addresses sent by the master.
WPx refers to wiper position data in the Counter Register
“I”: stands for the increment operation, SI held HIGH during active SCK phase (high).
“D”: stands for the decrement operation, SI held LOW during active SCK phase (high).
Read Wiper Counter Register (WCR)
device type
device
instruction
identifier
addresses
opcode
CS
Falling
Edge 0 1 0 1 0 0 A A 1 0 0 1
1 0
WCR
addresses
0
wiper position
(sent by X9400 on SO)
CS
Rising
W W W W W W
P P
0
0 0 P P P P P P Edge
1 0
5 4 3 2 1 0
Write Wiper Counter Register (WCR)
device type
device
instruction
identifier
addresses
opcode
CS
Falling
Edge 0 1 0 1 0 0 A A 1 0 1 0
1 0
WCR
addresses
0
Data Byte
(sent by Host on SI)
CS
Rising
W W W W W W
P P
0
0 0 P P P P P P Edge
1 0
5 4 3 2 1 0
Read Data Register (DR)
device type
device
instruction DR and WCR
Data Byte
identifier
addresses
opcode
addresses
(sent by X9400 on SO)
CS
CS
Falling
Rising
W W W W W W
Edge 0 1 0 1 0 0 A A 1 0 1 1 R R P P 0 0 P P P P P P Edge
1 0
1 0 1 0
5 4 3 2 1 0
Write Data Register (DR)
device type
device
identifier
addresses
instruction
opcode
DR and WCR
addresses
CS
Falling
Edge 0 1 0 1 0 0 A A 1 1 0 0 R
1 0
1
R
0
P
1
P
0
Data Byte
(sent by host on SI)
CS
W W W W W W Rising
0 0 P P P P P P Edge
5 4 3 2 1 0
HIGH-VOLTAGE
WRITE CYCLE
Transfer Data Register (DR) to Wiper Counter Register (WCR)
device type
device
instruction DR and WCR
CS
CS
identifier
addresses
opcode
addresses
Falling
Rising
Edge 0 1 0 1 0 0 A A 1 1 0 1 R R P P Edge
1 0
1 0 1 0
Transfer Wiper Counter Register (WCR) to Data Register (DR)
device type
device
instruction DR and WCR
CS
CS
identifier
addresses
opcode
addresses
Falling
Rising
Edge 0 1 0 1 0 0 A A 1 1 1 0 R R P P Edge
1 0
1 0 1 0
8
HIGH-VOLTAGE
WRITE CYCLE
FN8189.1
March 31, 2005
X9400
Increment/Decrement Wiper Counter Register (WCR)
device type
device
instruction
WCR
increment/decrement
CS
CS
identifier
addresses
opcode
addresses (sent by master on SDA)
Falling
Rising
Edge 0 1 0 1 0 0 A A 0 0 1 0 X X P P I/ I/ . . . . I/ I/ Edge
1 0
1 0 D D
D D
Global Transfer Data Register (DR) to Wiper Counter Register (WCR)
device type
device
instruction
DR
CS
CS
identifier
addresses
opcode
addresses
Falling
Rising
Edge 0 1 0 1 0 0 A A 0 0 0 1 R R 0 0 Edge
1 0
1 0
Global Transfer Wiper Counter Register (WCR) to Data Register (DR)
device type
device
instruction
DR
CS
CS
identifier
addresses
opcode
addresses
Falling
Rising
Edge 0 1 0 1 0 0 A A 1 0 0 0 R R 0 0 Edge
1 0
1 0
HIGH-VOLTAGE
WRITE CYCLE
Read Status
device type
device
instruction
wiper
Data Byte
identifier
addresses
opcode
addresses
(sent by X9400 on SO)
CS
CS
Falling
Rising
W
Edge 0 1 0 1 0 0 A A 0 1 0 1 0 0 0 1 0 0 0 0 0 0 0 I Edge
1 0
P
9
FN8189.1
March 31, 2005
X9400
ABSOLUTE MAXIMUM RATINGS
COMMENT
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 V+ (referenced to VSS) ........................ 10V
Voltage on V- (referenced to VSS) ........................-10V
(V+) - (V-)............................................................... 12V
Any VH ....................................................................V+
Any VL ...................................................................... VLead temperature (soldering, 10 seconds)........ 300°C
IW (10 seconds)................................................±12mA
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
Temp
Commercial
Industrial
Min.
0°C
-40°C
Max.
Device
X9400
X9400-2.7
+70°C
+85°C
Supply Voltage (VCC) Limits
5V ± 10%
2.7V to 5.5V
ANALOG CHARACTERISTICS (Over recommended operating conditions unless otherwise stated.)
Symbol
RTOTAL
IW
RW
Parameter
Min.
End to end resistance
Power rating
Wiper current
Wiper resistance
Limits
Typ.
Max.
±20
50
±6
150
250
40
Vv+
VvVTERM
CH/CL/CW
IAL
Voltage on V+ Pin
X9400
X9400-2.7
Voltage on V- Pin
X9400
X9400-2.7
Voltage on any VH/RH or VL/RL Pin
Noise
Resolution
Absolute linearity (1)
Relative linearity (2)
Temperature coefficient of RTOTAL
Ratiometric temp. coefficient
Potentiometer capacitances
RH, RL, RW leakage current
+4.5
+2.7
-5.5
-5.5
V-
100
Ω
+5.5
+5.5
-4.5
-2.7
V+
V
-120
1.6
-1
-0.2
+1
+0.2
±300
±20
10/10/25
0.1
Unit
%
mW
mA
Ω
10
Test Conditions
25°C, each pot
Wiper Current = ± 1mA,
VCC = 3V
Wiper Current = ± 1mA,
VCC = 5V
V
V
dBV
%
MI(3)
MI(3)
ppm/°C
ppm/°C
pF
µA
Ref: 1kHz
Rw(n)(actual) - Rw(n)(expected)
Rw(n + 1) - [Rw(n) + MI]
See Spice Macromodel
VIN = VSS to VCC. Device is in
stand-by mode.
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 (RH - RL)/63, single pot
10
FN8189.1
March 31, 2005
X9400
D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.)
Limits
Symbol
Parameter
Min.
Typ.
Max.
Units
Test Conditions
400
µA
fSCK = 2MHz, SO = Open,
Other Inputs = VSS
ICC1
VCC supply current (Active)
ICC2
VCC supply current (Nonvolatile
Write)
1
mA
fSCK = 2MHz, SO = Open,
Other Inputs = VSS
ISB
VCC current (standby)
1
µA
SCK = SI = VSS, 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
CAPACITANCE
Symbol
COUT
(4)
CIN(4)
Test
Max.
Unit
Test Conditions
Output capacitance (SO)
8
pF
VOUT = 0V
Input capacitance (A0, A1, SI, and SCK)
6
pF
VIN = 0V
POWER-UP TIMING
Symbol
tPUR
(5)
tPUW(5)
tR VCC(4)
Parameter
Max.
Unit
Power-up to initiation of read operation
1
ms
Power-up to initiation of write operation
5
ms
50
V/msec
VCC Power-up ramp
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, RH, RL, and RW.
Voltage should not be applied to the potentiometer
pins before V+ or V- is applied. The VCC ramp rate
specifi-cation should be met, and any glitches or slope
changes in the VCC line should be held to <100mV if
possible. If VCC powers down, it should be held below
0.1V for more than 1 second before powering up again
in order for proper wiper register recall. Also, VCC
should not reverse polarity by more than 0.5V. Recall
of wiper position will not be complete until VCC, V+
and V-reach their final value.
11
Min.
0.2
EQUIVALENT A.C. LOAD CIRCUIT
5V
1533Ω
SDA Output
100pF
FN8189.1
March 31, 2005
X9400
A.C. TEST CONDITIONS
SYMBOL TABLE
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
WAVEFORM
Notes: (4) This parameter is periodically sampled and not 100% tested
(5) tPUR and tPUW are the delays required from the time the
third (last) power supply (VCC, V+ or V-) is stable until the
specific instruction can be issued. These parameters are
periodically sampled and not 100% tested.
SPICE Macro Model
RTOTAL
RH
CL
CH
CW
10pF
RL
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
10pF
25pF
RW
AC TIMING
Symbol
Parameter
Min.
Max.
Unit
2.0
MHz
fSCK
SSI/SPI clock frequency
tCYC
SSI/SPI clock cycle time
500
ns
tWH
SSI/SPI clock high time
200
ns
tWL
SSI/SPI clock low time
200
ns
tLEAD
Lead time
250
ns
tLAG
Lag time
250
ns
tSU
SI, SCK, HOLD and CS input setup time
50
ns
tH
SI, SCK, HOLD and CS input hold time
50
ns
tRI
SI, SCK, HOLD and CS input rise time
tFI
SI, SCK, HOLD and CS input fall time
tDIS
SO output disable time
tV
SO output valid time
tHO
SO output hold time
tRO
SO output rise time
tFO
SO output fall time
0
2
µs
2
µs
500
ns
100
ns
0
ns
50
50
ns
ns
HOLD time
400
ns
tHSU
HOLD setup time
100
ns
tHH
HOLD hold time
100
ns
tHZ
HOLD low to output in High Z
100
tLZ
HOLD high to output in Low Z
100
ns
TI
Noise suppression time constant at SI, SCK, HOLD and CS inputs
20
ns
tHOLD
ns
CS deselect time
2
µs
tWPASU
WP, A0 and A1 setup time
0
ns
tWPAH
WP, A0 and A1 hold time
0
ns
tCS
12
FN8189.1
March 31, 2005
X9400
HIGH-VOLTAGE WRITE CYCLE TIMING
Symbol
tWR
Parameter
Typ.
Max.
Unit
5
10
ms
High-voltage write cycle time (store instructions)
XDCP TIMING
Symbol
tWRPO
Parameter
Min. Max.
Unit
Wiper response time after the third (last) power supply is stable
10
µs
tWRL
Wiper response time after instruction issued (all load instructions)
10
µs
tWRID
Wiper response time from an active SCL/SCK edge (increment/decrement instruction)
450
ns
TIMING DIAGRAMS
Input Timing
tCS
CS
tLAG
tCYC
tLEAD
SCK
...
tSU
tH
tWL
...
MSB
SI
tRI
tFI
tWH
LSB
High Impedance
SO
Output Timing
CS
SCK
...
tV
MSB
SO
SI
tHO
tDIS
...
LSB
ADDR
13
FN8189.1
March 31, 2005
X9400
Hold Timing
CS
tHSU
tHH
SCK
...
tRO
tFO
SO
tHZ
tLZ
SI
tHOLD
HOLD
XDCP Timing (for All Load Instructions)
CS
SCK
...
tWRL
SI
...
MSB
LSB
VW/RW
SO
High Impedance
XDCP Timing (for Increment/Decrement Instruction)
CS
SCK
...
tWRID
...
VW/RW
ADDR
SI
Inc/Dec
Inc/Dec
...
High Impedance
SO
14
FN8189.1
March 31, 2005
X9400
Write Protect and Device Address Pins Timing
(Any Instruction)
CS
tWPASU
tWPAH
WP
A0
A1
15
FN8189.1
March 31, 2005
X9400
APPLICATIONS INFORMATION
Basic Configurations of Electronic Potentiometers
+VR
VR
VW/RW
I
Three terminal Potentiometer;
Variable voltage divider
Two terminal Variable Resistor;
Variable current
Application Circuits
Noninverting Amplifier
VS
Voltage Regulator
+
VO
–
VIN
VO (REG)
317
R1
R2
Iadj
R1
R2
VO = (1+R2/R1)VS
VO (REG) = 1.25V (1+R2/R1)+Iadj R2
Offset Voltage Adjustment
R1
Comparator with Hysteresis
R2
VS
VS
–
+
VO
100kΩ
–
VO
+
}
}
TL072
R1
R2
10kΩ
10kΩ
+12V
10kΩ
VUL = {R1/(R1+R2)} VO(max)
VLL = {R1/(R1+R2)} VO(min)
-12V
16
FN8189.1
March 31, 2005
X9400
Application Circuits (continued)
Attenuator
Filter
C
VS
+
R2
R1
VS
VO
–
–
R
VO
+
R3
R4
R2
All RS = 10kΩ
R1
GO = 1 + R2/R1
fc = 1/(2πRC)
VO = G VS
-1/2 ≤ G ≤ +1/2
R1
R2
}
}
Inverting Amplifier
Equivalent L-R Circuit
VS
R2
C1
–
VS
VO
+
+
–
R1
ZIN
VO = G VS
G = - R2/R1
R3
ZIN = R2 + s R2 (R1 + R3) C1 = R2 + s Leq
(R1 + R3) >> R2
Function Generator
C
R2
–
+
R1
–
} RA
+
} RB
frequency ∝ R1, R2, C
amplitude ∝ RA, RB
17
FN8189.1
March 31, 2005
X9400
PACKAGING INFORMATION
24-Lead Plastic Dual In-Line Package Type P
1.265 (32.13)
1.230 (31.24)
0.557 (14.15)
0.530 (13.46)
Pin 1 Index
Pin 1
0.080 (2.03)
0.065 (1.65)
1.100 (27.94)
Ref.
0.162 (4.11)
0.140 (3.56)
Seating
Plane
0.030 (0.76)
0.015 (0.38)
0.150 (3.81)
0.125 (3.18)
0.110 (2.79)
0.090 (2.29)
0.065 (1.65)
0.040 (1.02)
0.022 (0.56)
0.014 (0.36)
0.625 (15.87)
0.600 (15.24)
Typ. 0.010 (0.25)
0°
15°
NOTE:
1. ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
2. PACKAGE DIMENSIONS EXCLUDE MOLDING FLASH
18
FN8189.1
March 31, 2005
X9400
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)
19
FN8189.1
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X9400
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)
20
FN8189.1
March 31, 2005
X9400
Ordering Information
X9400
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
S24 = 24-Lead SOIC
V24 = 24-Lead TSSOP
Potentiometer Organization
Pot 0 Pot 1 Pot 2 Pot 3
W=
10kΩ 10kΩ 10kΩ 10kΩ
Y=
2.5kΩ 2.5kΩ 2.5kΩ 2.5kΩ
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
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21
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