Intersil ISL22313 Single digitally controlled potentiometer (xdcpâ ¢) Datasheet

ISL22313
®
Single Digitally Controlled Potentiometer (XDCP™)
Data Sheet
July 17, 2007
Low Noise, Low Power, I2C® Bus, 256 Taps
Features
The ISL22313 integrates a single digitally controlled
potentiometer (DCP), control logic and non-volatile memory
on a monolithic CMOS integrated circuit.
• 256 resistor taps
The digitally controlled potentiometer is implemented with a
combination of resistor elements and CMOS switches. The
position of the wipers are controlled by the user through the
I2C bus interface. The potentiometer has an associated
volatile Wiper Register (WR) and a non-volatile Initial Value
Register (IVR) that can be directly written to and read by the
user. The contents of the WR control the position of the
wiper. At power up the device recalls the contents of the
DCP’s IVR to the WR.
The ISL22313 also has 14 general purpose non-volatile
registers that can be used as storage of lookup table for
multiple wiper position or any other valuable information.
The ISL22313 features a dual supply, that is beneficial for
applications requiring a bipolar range for DCP terminals
between V- and VCC.
FN6421.0
• I2C serial interface
- Two address pins, up to four devices per bus
• Non-volatile EEPROM storage of wiper position
• 14 General Purpose non-volatile registers
• High reliability
- Endurance: 1,000,000 data changes per bit per register
- Register data retention: 50 years @ T≤+55°C
• Wiper resistance: 70Ω typical @ 1mA
• Standby current <2.5µA max
• Shutdown current <2.5µA max
• Dual power supply
- VCC = 2.25V to 5.5V
- V- = -2.25V to -5.5V
• DCP terminal voltage from V- to VCC
• 10kΩ, 50kΩ or 100kΩ total resistance
The DCP 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.
• 10 Lead MSOP
Pinout
• Pb-free plus anneal product (RoHS compliant)
• Extended industrial temperature range: -40 to +125°C
ISL22313
(10 LD MSOP)
TOP VIEW
O
SCL
1
10
VCC
SDA
2
9
RH
A1
3
8
RW
4
7
RL
5
6
GND
A0
V-
Ordering Information
PART
NUMBER
(Notes 1, 2)
PART
MARKING
RESISTANCE
OPTION
(kΩ)
TEMP.
RANGE
(°C)
PACKAGE
(Pb-Free)
PKG. DWG. #
ISL22313TFU10Z
313TZ
100
-40 to +125
10 Ld MSOP
M10.118
ISL22313UFU10Z
313UZ
50
-40 to +125
10 Ld MSOP
M10.118
ISL22313WFU10Z
313WZ
10
-40 to +125
10 Ld MSOP
M10.118
NOTES:
1. Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are
MSL classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
2. Add “-TK” suffix for 1,000 Tape and Reel option
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) and XDCP are registered trademarks of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2007. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
ISL22313
Block Diagram
V-
VCC
SCL
SDA
I2C
INTERFACE
A1
A0
POWER UP
INTERFACE,
CONTROL
AND
STATUS
LOGIC
RH
WR
VOLATILE
REGISTER
AND
WIPER
CONTROL
CIRCUITRY
NON-VOLATILE
REGISTERS
RL
RW
GND
Pin Descriptions
MSOP PIN
SYMBOL
DESCRIPTION
1
SCL
Open drain I2C interface clock input
2
SDA
Open drain Serial data I/O for the I2C interface
3
A1
Device address input for the I2C interface
4
A0
Device address input for the I2C interface
5
V-
Negative supply pin
6
GND
7
RL
“Low” terminal of DCP
8
RW
“Wiper” terminal of DCP
9
RH
“High” terminal of DCP
10
VCC
2
Device ground pin
Power supply pin
FN6421.0
July 17, 2007
ISL22313
Absolute Maximum Ratings
Thermal Information
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Voltage at any Digital Interface Pin
with Respect to GND . . . . . . . . . . . . . . . . . . . . . -0.3V to VCC+0.3
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to +6V
V- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6V to 0.3V
Voltage at any DCP Pin with
respect to GND. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V- to VCC
IW (10s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±6mA
Latchup . . . . . . . . . . . . . . . . . . . . . . . . . Class II, Level A at +125°C
ESD
Human Body Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3kV
Machine Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .400V
Thermal Resistance (Typical, Note 3)
θJA (°C/W)
10 Lead MSOP. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
120
Maximum Junction Temperature (Plastic Package). . . . . . . . +150°C
Pb-free reflow profile . . . . . . . . . . . . . . . . . . . . . . . . . .see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
Recommended Operating Conditions
Temperature Range (Full Industrial) . . . . . . . . . . . .-40°C to +125°C
Power Rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15mW
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.25V to 5.5V
V- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -2.25V to -5.5V
Max Wiper Current Iw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±3.0mA
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and
result in failures not covered by warranty.
NOTE:
3. θJA is measured with the component mounted on a high effective thermal conductivity test board in free air. See Tech Brief TB379 for details.
Analog Specifications
SYMBOL
RTOTAL
Over recommended operating conditions unless otherwise stated. Limits are established by characterization.
MIN
TYP
MAX
(Note 18) (Note 4) (Note 18)
UNIT
W option
10
kΩ
U option
50
kΩ
T option
100
kΩ
PARAMETER
RH to RL resistance
TEST CONDITIONS
RH to RL resistance tolerance
End-to-End Temperature Coefficient
VRH, VRL
RW
CH/CL/CW
(Note 16)
ILkgDCP
-20
+20
%
W option
±150
ppm/°C
U, T option
±50
ppm/°C
DCP terminal voltage
VRH and VRL to GND
Wiper resistance
RH - floating, VRL = V-, force IW current to
the wiper, IW = (VCC - VRL)/RTOTAL
Potentiometer capacitance
See Macro Model below.
Leakage on DCP pins
Voltage at pin from GND to VCC
V70
VCC
V
250
Ω
10/10/25
pF
0.1
1
µA
LSB
(Note 5)
VOLTAGE DIVIDER MODE (V- @ RL; VCC @ RH; measured at RW, unloaded)
INL
(Note 9)
DNL
(Note 8)
Integral non-linearity
Differential non-linearity
ZSerror
(Note 6)
Zero-scale error
FSerror
(Note 7)
Full-scale error
TCV
Ratiometric temperature coefficient
(Notes 10, 16)
3
W option
-1.5
±0.5
1.5
U, T option
-1.0
±0.2
1.0
W option
-1.0
±0.4
1.0
U, T option
-0.5
±0.15
0.5
W option
0
1
5
U, T option
0
0.5
2
W option
-5
-1
0
U, T option
-2
-1
0
DCP register set to 80 hex
±4
LSB
(Note 5)
LSB
(Note 5)
LSB
(Note 5)
ppm/°C
FN6421.0
July 17, 2007
ISL22313
Analog Specifications
SYMBOL
fcutoff
(Note 16)
Over recommended operating conditions unless otherwise stated. Limits are established by characterization.
(Continued)
MIN
TYP
MAX
(Note 18) (Note 4) (Note 18)
UNIT
Wiper at midpoint (80hex) W option (10k)
1000
kHz
Wiper at midpoint (80hex) U option (50k)
250
kHz
Wiper at midpoint (80hex) T option (100k)
120
kHz
PARAMETER
-3dB cut off frequency
TEST CONDITIONS
RESISTOR MODE (Measurements between RW and RL with RH not connected, or between RW and RH with RL not connected)
RINL
(Note 14)
RDNL
(Note 13)
Roffset
(Note 12)
Integral non-linearity
Differential non-linearity
Offset
TCR
Resistance temperature coefficient
(Notes 15, 16)
W option
-3
±1.5
3
MI
(Note 11)
U, T option
-1
±0.3
1
MI
(Note 11)
W option
-1.5
±0.4
1.5
MI
(Note 11)
U, T option
-0.5
±0.15
0.5
MI
(Note 11)
W option
0
1
5
MI
(Note 11)
U, T option
0
0.5
2
MI
(Note 11)
DCP register set between 32 hex and FF hex
±50
ppm/°C
Operating Specifications Over the recommended operating conditions unless otherwise specified. Limits are established by
characterization.
SYMBOL
ICC1
IV-1
PARAMETER
VCC Supply Current (volatile
write/read)
TYP
(Note 4)
MAX
(Note 18)
UNIT
VCC = +5.5V, V- = -5.5V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
0.07
0.15
mA
VCC = +2.25V, V- = -2.25V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
0.02
0.05
mA
TEST CONDITIONS
V- Supply Current (volatile write/read) V- = -5.5V, VCC = +5.5V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
V- = -2.25V, VCC = +2.25V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
ICC2
IV-2
VCC Supply Current (non-volatile
write/read)
MIN
(Note 18)
-1
-0.18
mA
-0.4
-0.06
mA
VCC = +5.5V, V- = -5.5V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
1
2
mA
VCC = +2.25V, V- = -2.25V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
0.3
0.7
mA
V- Supply Current (non-volatile
write/read)
V- = -5.5V, VCC = +5.5V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
-2
-1.2
mA
V- Supply Current (non-volatile
write/read)
V- = -2.25V, VCC = +2.25V, fSCL = 400kHz;
SDA = Open; (for I2C, active, read and write
states)
-0.7
-0.4
mA
4
FN6421.0
July 17, 2007
ISL22313
Operating Specifications Over the recommended operating conditions unless otherwise specified. Limits are established by
characterization. (Continued)
SYMBOL
ISB
PARAMETER
VCC Current (standby)
TYP
(Note 4)
MAX
(Note 18)
UNIT
0.2
1.5
µA
VCC = +5.5V, V- = -5.5V @ +125°C, I2C
interface in standby state
1
2.5
µA
VCC = +2.25V, V- = -2.25V @ +85°C, I2C
interface in standby state
0.1
1
µA
VCC = +2.25V, V- = -2.25V @ +125°C, I2C
interface in standby state
0.5
2
µA
TEST CONDITIONS
MIN
(Note 18)
VCC = +5.5V, V- = -5.5V @ +85°C, I2C
interface in standby state
IV-SB
ISD
IV-SB
ILkgDig
V- Current (standby)
VCC Current (shutdown)
V- Current (standby)
V- = -5.5V, VCC = +5.5V @ +85°C, I2C
interface in standby state
-2.5
-0.7
µA
V- = -5.5V, VCC = +5.5V @ +125°C, I2C
interface in standby state
-4
-3
µA
V- = -2.25V, VCC = +2.25V @ +85°C, I2C
interface in standby state
-1.5
-0.3
µA
V- = -2.25V, VCC = +2.25V @ +125°C, I2C
interface in standby state
-3
-1
µA
VCC = +5.5V, V- = -5.5V @ +85°C, I2C
interface in standby state
0.2
1.5
µA
VCC = +5.5V, V- = -5.5V @ +125°C, I2C
interface in standby state
1
2.5
µA
VCC = +2.25V, V- = -2.25V @ +85°C, I2C
interface in standby state
0.1
1
µA
VCC = +2.25V, V- = -2.25V @ +125°C, I2C
interface in standby state
0.5
2
µA
V- = -5.5V, VCC = +5.5V @ +85°C, I2C
interface in standby state
-2.5
-0.7
µA
V- = -5.5V, VCC = +5.5V @ +125°C, I2C
interface in standby state
-4
-3
µA
V- = -2.25V, VCC = +2.25V @ +85°C, I2C
interface in standby state
-1.5
-0.3
µA
V- = -2.25V, VCC = +2.25V @ +125°C, I2C
interface in standby state
-3
-1
µA
Leakage current, at pins A0, A1, SDA, Voltage at pin from GND to VCC
and SCL
-1
1
µA
tDCP
(Note 16)
DCP wiper response time
SCL falling edge of last bit of DCP data byte
to wiper new position
1.5
µs
tShdnRec
(Note 16)
DCP recall time from shutdown mode SCL falling edge of last bit of ACR data byte
to wiper stored position and RH connection
1.5
µs
Vpor
Power-on recall voltage
Minimum VCC at which memory recall occurs
VCC Ramp VCC ramp rate
tD
1.9
2.1
0.2
Power-up delay
V
V/ms
5
VCC above Vpor, to DCP Initial Value
Register recall completed, and I2C Interface
in standby state
ms
EEPROM SPECIFICATION
EEPROM Endurance
EEPROM Retention
tWC
(Note 17)
Non-volatile Write cycle time
5
Temperature T ≤ +55°C
1,000,000
Cycles
50
Years
12
20
ms
FN6421.0
July 17, 2007
ISL22313
Operating Specifications Over the recommended operating conditions unless otherwise specified. Limits are established by
characterization. (Continued)
SYMBOL
PARAMETER
TEST CONDITIONS
MIN
(Note 18)
TYP
(Note 4)
MAX
(Note 18)
UNIT
SERIAL INTERFACE SPECS
VIL
A1, A0, SDA, and SCL input buffer
LOW voltage
-0.3
0.3*VCC
V
VIH
A1, A0, SDA, and SCL input buffer
HIGH voltage
0.7*VCC
VCC + 0.
3
V
Hysteresis
(Note 16)
SDA and SCL input buffer hysteresis
0.05*VCC
VOL
(Note 16)
SDA output buffer LOW voltage,
sinking 4mA
Cpin
(Note 16)
fSCL
0
V
0.4
V
A1, A0, SDA, and SCL pin
capacitance
10
pF
SCL frequency
400
kHz
tsp
Pulse width suppression time at SDA
and SCL inputs
Any pulse narrower than the max spec is
suppressed
50
ns
tAA
(Note 16)
SCL falling edge to SDA output data
valid
SCL falling edge crossing 30% of VCC, until
SDA exits the 30% to 70% of VCC window
900
ns
tBUF
(Note 16)
Time the bus must be free before the
start of a new transmission
SDA crossing 70% of VCC during a STOP
condition, to SDA crossing 70% of VCC
during the following START condition
1300
ns
tLOW
Clock LOW time
Measured at the 30% of VCC crossing
1300
ns
tHIGH
Clock HIGH time
Measured at the 70% of VCC crossing
600
ns
tSU:STA
START condition setup time
SCL rising edge to SDA falling edge; both
crossing 70% of VCC
600
ns
tHD:STA
START condition hold time
From SDA falling edge crossing 30% of VCC
to SCL falling edge crossing 70% of VCC
600
ns
tSU:DAT
Input data setup time
From SDA exiting the 30% to 70% of VCC
window, to SCL rising edge crossing 30% of
VCC
100
ns
tHD:DAT
Input data hold time
From SCL rising edge crossing 70% of VCC
to SDA entering the 30% to 70% of VCC
window
0
ns
tSU:STO
STOP condition setup time
From SCL rising edge crossing 70% of VCC,
to SDA rising edge crossing 30% of VCC
600
ns
tHD:STO
STOP condition hold time for read, or
volatile only write
From SDA rising edge to SCL falling edge;
both crossing 70% of VCC
1300
ns
tDH
(Note 16)
Output data hold time
From SCL falling edge crossing 30% of VCC,
until SDA enters the 30% to 70% of VCC
window
0
ns
tR
(Note 16)
SDA and SCL rise time
From 30% to 70% of VCC
20 +
0.1 * Cb
250
ns
tF
(Note 16)
SDA and SCL fall time
From 70% to 30% of VCC
20 +
0.1 * Cb
250
ns
Cb
(Note 16)
Capacitive loading of SDA or SCL
Total on-chip and off-chip
10
400
pF
Rpu
(Note 16)
SDA and SCL bus pull-up resistor
off-chip
Maximum is determined by tR and tF
For Cb = 400pF, max is about 2kΩ~2.5kΩ
For Cb = 40pF, max is about 15kΩ~20kΩ
1
6
kΩ
FN6421.0
July 17, 2007
ISL22313
Operating Specifications Over the recommended operating conditions unless otherwise specified. Limits are established by
characterization. (Continued)
SYMBOL
PARAMETER
MIN
(Note 18)
TEST CONDITIONS
TYP
(Note 4)
MAX
(Note 18)
UNIT
tSU:A
A1 and A0 setup time
Before START condition
600
ns
tHD:A
A1 and A0 hold time
After STOP condition
600
ns
NOTES:
4. Typical values are for TA = +25°C and 3.3V supply voltage.
5. LSB: [V(RW)255 – V(RW)0]/255. V(RW)255 and V(RW)0 are V(RW) for the DCP register set to FF hex and 00 hex respectively. LSB is the
incremental voltage when changing from one tap to an adjacent tap.
6. ZS error = V(RW)0/LSB.
7. FS error = [V(RW)255 – VCC]/LSB.
8. DNL = [V(RW)i – V(RW)i-1]/LSB-1, for i = 1 to 255. i is the DCP register setting.
9. INL = [V(RW)i – i • LSB – V(RW)0]/LSB for i = 1 to 255
Max ( V ( RW ) i ) – Min ( V ( RW ) i )
10 6
10. TC = --------------------------------------------------------------------------------------------- × ----------------- for i = 16 to 255 decimal, T = -40°C to +125°C. Max( ) is the maximum value of the wiper
V
[ Max ( V ( RW ) i ) + Min ( V ( RW ) i ) ] ⁄ 2 +165°C voltage and Min ( ) is the minimum value of the wiper voltage over the temperature range.
11. MI = |RW255 – RW0|/255. MI is a minimum increment. RW255 and RW0 are the measured resistances for the DCP register set to FF hex and
00 hex respectively.
12. Roffset = RW0/MI, when measuring between RW and RL.
Roffset = RW255/MI, when measuring between RW and RH.
13. RDNL = (RWi – RWi-1)/MI -1, for i = 16 to 255.
14. RINL = [RWi – (MI • i) – RW0]/MI, for i = 16 to 255.
6
15.
for i = 16 to 255, T = -40°C to +125°C. Max( ) is the maximum value of the resistance and Min ( ) is
[ Max ( Ri ) – Min ( Ri ) ]
10
TC R = ---------------------------------------------------------------- × ----------------- the minimum value of the resistance over the temperature range.
165°C
[ Max ( Ri ) + Min ( Ri ) ] ⁄ 2 +
16. Limits should be considered typical and are not production tested.
17. tWC is the time from a valid STOP condition at the end of a Write sequence of I2C serial interface, to the end of the self-timed internal non-volatile
write cycle.
18. Parts are 100% tested at +25°C. Over temperature limits established by characterization and are not production tested.
DCP Macro Model
RTOTAL
RH
CL
CH
CW
10pF
RL
10pF
25pF
RW
SDA vs SCL Timing
tF
SCL
tHIGH
tLOW
tsp
tR
tSU:DAT
tSU:STA
tHD:DAT
tSU:STO
tHD:STA
SDA
(INPUT TIMING)
tAA
tDH
tBUF
SDA
(OUTPUT TIMING)
7
FN6421.0
July 17, 2007
ISL22313
A0 and A1 Pin Timing
STOP
START
SCL
CLK 1
SDA
tSU:A
tHD:A
A0, A1
Typical Performance Curves
80
2.0
T = +125ºC
1.5
60
STANDBY CURRENT (µA)
WIPER RESISTANCE (Ω)
70
T = +25ºC
50
40
30
T = -40ºC
20
10
1.0
ICC
0.5
0
-0.5
IV-1.0
-1.5
0
0
50
100
150
200
-2.0
-40
250
0
TAP POSITION (DECIMAL)
40
80
120
TEMPERATURE (°C)
FIGURE 2. STANDBY ICC AND IV- vs TEMPERATURE
FIGURE 1. WIPER RESISTANCE vs TAP POSITION
[ I(RW) = VCC/RTOTAL ] FOR 10kΩ (W)
0.50
0.50
VCC = 5.5V
T = +25ºC
T = +25ºC
VCC = 2.25V
0.25
INL (LSB)
DNL (LSB)
0.25
0
0
-0.25
-0.25
VCC = 5.5V
VCC = 2.25V
-0.50
-0.50
0
50
100
150
200
TAP POSITION (DECIMAL)
FIGURE 3. DNL vs TAP POSITION IN VOLTAGE DIVIDER
MODE FOR 10kΩ (W)
8
250
0
50
100
150
200
250
TAP POSITION (DECIMAL)
FIGURE 4. INL vs TAP POSITION IN VOLTAGE DIVIDER
MODE FOR 10kΩ (W)
FN6421.0
July 17, 2007
ISL22313
Typical Performance Curves
(Continued)
2.0
0
10k
-1
1.2
0.8
50k
VCC = 2.25V
VCC = 5.5V
FS ERROR (LSB)
ZS ERROR (LSB)
1.6
0.4
VCC = 2.25V
50k
VCC = 5.5V
-2
-3
10k
-4
0
-40
0
40
80
-5
-40
120
0
TEMPERATURE (ºC)
40
80
120
TEMPERATURE (ºC)
FIGURE 5. ZS ERROR vs TEMPERATURE
FIGURE 6. FS ERROR vs TEMPERATURE
2.0
0.5
T = +25ºC
T = +25ºC
VCC = 5.5V
1.5
VCC = 2.25V
1.0
RINL (MI)
RDNL (MI)
0.25
0
0.5
-0.25
0
VCC = 2.25V
VCC = 5.5V
-0.50
-0.5
0
50
100
150
200
250
0
50
100
150
200
250
TAP POSITION (DECIMAL)
TAP POSITION (DECIMAL)
FIGURE 7. DNL vs TAP POSITION IN RHEOSTAT MODE FOR
10kΩ (W)
FIGURE 8. INL vs TAP POSITION IN RHEOSTAT MODE FOR
10kΩ (W)
200
1.60
10k
160
10k
0.80
TCv (ppm/ºC)
RTOTAL CHANGE (%)
1.20
5.5V
0.40
80
50k
40
0.00
50k
2.25V
-0.40
-40
120
0
0
40
80
TEMPERATURE (ºC)
FIGURE 9. END TO END RTOTAL % CHANGE vs
TEMPERATURE
9
120
16
66
116
166
216
266
TAP POSITION (DECIMAL)
FIGURE 10. TC FOR VOLTAGE DIVIDER MODE IN ppm
FN6421.0
July 17, 2007
ISL22313
Typical Performance Curves
(Continued)
500
INPUT
TCr (ppm/ºC)
OUTPUT
10k
400
300
200
50k
100
WIPER AT MID POINT (POSITION 80h)
RTOTAL = 10kΩ
0
16
66
116
166
216
TAP POSITION (DECIMAL)
FIGURE 11. TC FOR RHEOSTAT MODE IN ppm
FIGURE 12. FREQUENCY RESPONSE (1MHz)
CS
SCL
WIPER UNLOADED,
WIPER
MOVEMENT FROM 0h to FFh
FIGURE 13. MIDSCALE GLITCH, CODE 7Fh TO 80h
FIGURE 14. LARGE SIGNAL SETTLING TIME
Pin Description
Bus Interface Pins
Potentiometers Pins
Serial Data Input/Output (SDA)
RH and RL
The high (RH) and low (RL) terminals of the ISL22313 are
equivalent to the fixed terminals of a mechanical
potentiometer. RH and RL are referenced to the relative
position of the wiper and not the voltage potential on the
terminals. With WR set to 255 decimal, the wiper will be
closest to RH, and with the WR set to 0, the wiper is closest
to RL.
RW
RW is the wiper terminal, and it is equivalent to the movable
terminal of a mechanical potentiometer. The position of the
wiper within the array is determined by the WR register.
10
The SDA is a bidirectional serial data input/output pin for I2C
interface. It receives device address, operation code, wiper
address and data from an I2C external master device at the
rising edge of the serial clock SCL, and it shifts out data after
each falling edge of the serial clock.
SDA requires an external pull-up resistor, since it is an open
drain input/output.
Serial Clock (SCL)
This input is the serial clock of the I2C serial interface. SCL
requires an external pull-up resistor, since it is an open drain
input.
FN6421.0
July 17, 2007
ISL22313
Device Address (A1, A0)
Memory Description
The address inputs are used to set the least significant 2 bits
of the 7-bit I2C interface slave address. A match in the slave
address serial data stream must match with the Address
input pins in order to initiate communication with the
ISL22313. A maximum of four ISL22313 devices may
occupy the I2C serial bus (see Table 3).
The ISL22313 contains one non-volatile 8-bit Initial Value
Register (IVR), fourteen General Purpose non-volatile 8-bit
registers and two volatile 8-bit registers: Wiper Register (WR)
and Access Control Register (ACR). Memory map of ISL22313
is in Table 1. The non-volatile register (IVR) at address 0,
contains initial wiper position and volatile register (WR) contains
current wiper position.
Principles of Operation
The ISL22313 is an integrated circuit incorporating one DCP
with its associated registers, non-volatile memory and an I2C
serial interface providing direct communication between a
host and the potentiometer and memory. The resistor array
is comprised of individual resistors connected in series. At
either end of the array and between each resistor is an
electronic switch that transfers the potential at that point to
the wiper.
The electronic switches on the device operate in a “make
before break” mode when the wiper changes tap positions.
When the device is powered down, the last value stored in
IVR will be maintained in the non-volatile memory. When
power is restored, the contents of the IVR are recalled and
loaded into the WR to set the wiper to the initial value.
DCP Description
The DCP is implemented with a combination of resistor
elements and CMOS switches. The physical ends of each
DCP are equivalent to the fixed terminals of a mechanical
potentiometer (RH and RL pins). The RW pin of the DCP is
connected to intermediate nodes, and is equivalent to the
wiper terminal of a mechanical potentiometer. The position
of the wiper terminal within the DCP is controlled by an 8-bit
volatile Wiper Register (WR). When the WR of a DCP
contains all zeroes (WR[7:0]= 00h), its wiper terminal (RW)
is closest to its “Low” terminal (RL). When the WR register of
a DCP contains all ones (WR[7:0]= FFh), its wiper terminal
(RW) is closest to its “High” terminal (RH). As the value of
the WR increases from all zeroes (0) to all ones (255
decimal), the wiper moves monotonically from the position
closest to RL to the position closest to RH. At the same time,
the resistance between RW and RL increases monotonically,
while the resistance between RH and RW decreases
monotonically.
While the ISL22313 is being powered up, the WR is reset to
80h (128 decimal), which locates RW roughly at the center
between RL and RH. After the power supply voltage
becomes large enough for reliable non-volatile memory
reading, the WR will be reloaded with the value stored in a
non-volatile Initial Value Register (IVR).
The WR and IVR can be read or written to directly using the
I2C serial interface as described in the following sections.
11
TABLE 1. MEMORY MAP
ADDRESS
(hex)
NON-VOLATILE
VOLATILE
10
N/A
ACR
F
Reserved
E
General Purpose
N/A
D
General Purpose
N/A
C
General Purpose
N/A
B
General Purpose
N/A
A
General Purpose
N/A
9
General Purpose
N/A
8
General Purpose
N/A
7
General Purpose
N/A
6
General Purpose
N/A
5
General Purpose
N/A
4
General Purpose
N/A
3
General Purpose
N/A
2
General Purpose
N/A
1
General Purpose
N/A
0
IVR
WR
The non-volatile IVR and volatile WR registers are
accessible with the same address.
The Access Control Register (ACR) contains information
and control bits described below in Table 2.
The VOL bit (ACR[7]) determines whether the access to
wiper registers WR or initial value registers IVR.
TABLE 2. ACCESS CONTROL REGISTER (ACR)
BIT #
7
6
5
4
3
2
1
0
NAME
VOL
SHDN
WIP
0
0
0
0
0
If VOL bit is 0, the non-volatile IVR register is accessible. If
VOL bit is 1, only the volatile WR is accessible. Note: Value
is written to IVR register also is written to the WR. The
default value of this bit is 0.
The SHDN bit (ACR[6]) disables or enables Shutdown mode.
When this bit is 0, i.e. DCP is forced to end-to-end open
circuit and RW is shorted to RL as shown on Figure 15.
Default value of the SHDN bit is 1.
FN6421.0
July 17, 2007
ISL22313
All I2C interface operations must begin with a START
condition, which is a HIGH to LOW transition of SDA while
SCL is HIGH. The ISL22313 continuously monitors the SDA
and SCL lines for the START condition and does not
respond to any command until this condition is met (see
Figure 16). A START condition is ignored during the powerup of the device.
RH
RW
RL
FIGURE 15. DCP CONNECTION IN SHUTDOWN MODE
The WIP bit (ACR[5]) is a read-only bit. It indicates that nonvolatile write operation is in progress. It is impossible to write
to the WR or ACR while WIP bit is 1.
I2C Serial Interface
The ISL22313 supports an I2C 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 always
initiates data transfers and provides the clock for both
transmit and receive operations. Therefore, the ISL22313
operates as a slave device in all applications.
All communication over the I2C interface is conducted by
sending the MSB of each byte of data first.
Protocol Conventions
Data states on the SDA line must change only during SCL
LOW periods. SDA state changes during SCL HIGH are
reserved for indicating START and STOP conditions (see
Figure 16). On power-up of the ISL22313, the SDA pin is in
the input mode.
All I2C interface operations must be terminated by a STOP
condition, which is a LOW to HIGH transition of SDA while
SCL is HIGH (see Figure 16). A STOP condition at the end
of a read operation, or at the end of a write operation places
the device in its standby mode.
An ACK (Acknowledge) is a software convention used to
indicate a successful data transfer. The transmitting device,
either master or slave, releases the SDA bus after
transmitting eight bits. During the ninth clock cycle, the
receiver pulls the SDA line LOW to acknowledge the
reception of the eight bits of data (see Figure 17).
The ISL22313 responds with an ACK after recognition of a
START condition followed by a valid Identification Byte, and
once again after successful receipt of an Address Byte. The
ISL22313 also responds with an ACK after receiving a Data
Byte of a write operation. The master must respond with an
ACK after receiving a Data Byte of a read operation
A valid Identification Byte contains 10100 as the five MSBs,
and the following two bits matching the logic values present
at pins A1 and A0. The LSB is the Read/Write bit. Its value is
“1” for a Read operation and “0” for a Write operation (see
Table 3).
TABLE 3. IDENTIFICATION BYTE FORMAT
LOGIC VALUES AT PINS A1 AND A0, RESPECTIVELY
1
0
1
0
0
(MSB)
A1
A0
R/W
(LSB)
SCL
SDA
START
DATA
STABLE
DATA
CHANGE
DATA
STABLE
STOP
FIGURE 16. VALID DATA CHANGES, START AND STOP CONDITIONS
12
FN6421.0
July 17, 2007
ISL22313
SCL FROM
MASTER
1
8
9
SDA OUTPUT FROM
TRANSMITTER
HIGH IMPEDANCE
HIGH IMPEDANCE
SDA OUTPUT FROM
RECEIVER
START
ACK
FIGURE 17. ACKNOWLEDGE RESPONSE FROM RECEIVER
WRITE
S
T
A
R
T
SIGNALS FROM
THE MASTER
SIGNAL AT SDA
IDENTIFICATION
BYTE
ADDRESS
BYTE
1 0 1 0 0 A1 A0 0
SIGNALS FROM
THE SLAVE
S
T
O
P
DATA
BYTE
0 0 0 0
A
C
K
A
C
K
A
C
K
FIGURE 18. BYTE WRITE SEQUENCE
SIGNALS
FROM THE
MASTER
S
T
A
R
T
SIGNAL AT SDA
IDENTIFICATION
BYTE WITH
R/W = 0
ADDRESS
BYTE
1 0 1 0 0 A1 A0 0
A
C
K
S
A T
C O
K P
A
C
K
1 0 1 0 0 A1 A0 1
0 0 0 0
A
C
K
SIGNALS FROM
THE SLAVE
S
T
A IDENTIFICATION
R
BYTE WITH
T
R/W = 1
A
C
K
A
C
K
FIRST READ
DATA BYTE
LAST READ
DATA BYTE
FIGURE 19. READ SEQUENCE
Write Operation
Read Operation
A Write operation requires a START condition, followed by a
valid Identification Byte, a valid Address Byte, a Data Byte,
and a STOP condition. After each of the three bytes, the
ISL22313 responds with an ACK. At this time, the device
enters its standby state (see Figure 18).
A Read operation consist of a three byte instruction followed
by one or more Data Bytes (see Figure 19). The master
initiates the operation issuing the following sequence: a
START, the Identification byte with the R/W bit set to “0”, an
Address Byte, a second START, and a second Identification
byte with the R/W bit set to “1”. After each of the three bytes,
the ISL22313 responds with an ACK. Then the ISL22313
transmits Data Bytes as long as the master responds with an
ACK during the SCL cycle following the eighth bit of each
byte. The Data Bytes are from the registers indicated by an
internal pointer. This pointer initial value is determined by the
Address Byte in the Read operation instruction, and
The non-volatile write cycle starts after STOP condition is
determined and it requires up to 20ms delay for the next
non-volatile write. Thus, non-volatile registers must be
written individually.
13
FN6421.0
July 17, 2007
ISL22313
increments by one during transmission of each Data Byte.
After reaching the memory location 0Fh, the pointer “rolls
over” to 00h, and the device continues to output data for
each ACK received.The master terminates the read
operation issuing a NACK (ACK ) and a STOP condition
following the last bit of the last Data Byte (see Figure 19).
Applications Information
When stepping up through each tap in voltage divider mode,
some tap transition points can result in noticeable voltage
transients (or overshoot/undershoot) resulting from the
sudden transition from a very low impedance “make” to a
much higher impedance “break within an extremely short
period of time (<50ns). Two such code transitions are EFh to
F0h, and 0Fh to 10h. Note that all switching transients will
settle well within the settling time as stated in the datasheet.
A small capacitor can be added externally to reduce the
amplitude of these voltage transients, but that will also
reduce the useful bandwidth of the circuit, thus this may not
be a good solution for some applications. It may be a good
idea, in that case, to use fast amplifiers in a signal chain for
fast recovery.
14
FN6421.0
July 17, 2007
ISL22313
Mini Small Outline Plastic Packages (MSOP)
N
M10.118 (JEDEC MO-187BA)
10 LEAD MINI SMALL OUTLINE PLASTIC PACKAGE
E1
E
INCHES
SYMBOL
-B-
INDEX
AREA
1 2
0.20 (0.008)
A B C
TOP VIEW
4X θ
0.25
(0.010)
R1
R
GAUGE
PLANE
A
SEATING
PLANE -C-
A2
A1
b
-He
D
0.10 (0.004)
4X θ
L
SEATING
PLANE
C
-A0.20 (0.008)
C
C
a
SIDE VIEW
CL
E1
0.20 (0.008)
C D
-B-
MILLIMETERS
MAX
MIN
MAX
NOTES
A
0.037
0.043
0.94
1.10
-
A1
0.002
0.006
0.05
0.15
-
A2
0.030
0.037
0.75
0.95
-
b
0.007
0.011
0.18
0.27
9
c
0.004
0.008
0.09
0.20
-
D
0.116
0.120
2.95
3.05
3
E1
0.116
0.120
2.95
3.05
4
e
L1
MIN
0.020 BSC
0.50 BSC
-
E
0.187
0.199
4.75
5.05
-
L
0.016
0.028
0.40
0.70
6
L1
0.037 REF
0.95 REF
-
N
10
10
7
R
0.003
-
0.07
-
-
R1
0.003
-
0.07
-
-
θ
5o
15o
5o
15o
-
α
0o
6o
0o
6o
-
END VIEW
Rev. 0 12/02
NOTES:
1. These package dimensions are within allowable dimensions of
JEDEC MO-187BA.
2. Dimensioning and tolerancing per ANSI Y14.5M-1994.
3. Dimension “D” does not include mold flash, protrusions or gate
burrs and are measured at Datum Plane. Mold flash, protrusion
and gate burrs shall not exceed 0.15mm (0.006 inch) per side.
4. Dimension “E1” does not include interlead flash or protrusions
and are measured at Datum Plane. - H - Interlead flash and
protrusions shall not exceed 0.15mm (0.006 inch) per side.
5. Formed leads shall be planar with respect to one another within
0.10mm (.004) at seating Plane.
6. “L” is the length of terminal for soldering to a substrate.
7. “N” is the number of terminal positions.
8. Terminal numbers are shown for reference only.
9. Dimension “b” does not include dambar protrusion. Allowable
dambar protrusion shall be 0.08mm (0.003 inch) total in excess
of “b” dimension at maximum material condition. Minimum space
between protrusion and adjacent lead is 0.07mm (0.0027 inch).
10. Datums -A -H- .
and - B -
to be determined at Datum plane
11. Controlling dimension: MILLIMETER. Converted inch dimensions are for reference only
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
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15
FN6421.0
July 17, 2007
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