Intersil ISL90727 Digitally controlled potentiometer Datasheet

ISL90727, ISL90728
®
Single Volatile 128-Tap XDCP
Data Sheet
August 2, 2006
Digitally Controlled Potentiometer
(XDCP™)
Features
The Intersil ISL90727 and ISL90728 are digitally controlled
potentiometers (XDCP). Each device consists of a resistor
array, wiper switches, and a control section. The wiper
position is controlled by an I2C interface.
• I2C Serial Bus Interface
FN8247.4
• Volatile Solid-State Potentiometer
The potentiometer is implemented by a resistor array
composed of 127 resistive elements and a wiper switching
network. Between each element and at either end are tap
points accessible to the wiper terminal. The position of the
wiper element is controlled by the SDA and SCL inputs.
• DCP Terminal Voltage, 2.7V to 5.5V
• Low Tempco
- Rheostat - 45 ppm/°C typical
- Divider - 15 ppm/°C typical
• 128 Wiper Tap Points
- Wiper resistance 70Ω typ at VCC = 3.3V
• Low Power CMOS
- Active current, 200µA max
- Standby current, 500nA max
The device can be used in a wide variety of applications
including:
• Mechanical potentiometer replacement
• Available RTOTAL Values = 50kΩ, 10kΩ
• Transducer adjustment of pressure, temperature, position,
chemical, and optical sensors
• Power on Preset to Midscale
• Direct Replacement for AD5247
• RF amplifier biasing
• Packaging
- 6 Ld SC-70
• LCD brightness and contrast adjustment
• Gain control and offset adjustment
• Pb-Free Plus Anneal Available (RoHS Compliant)
Pinout
ISL90727, ISL90728
(6 LD SC-70)
TOP VIEW
VDD 1
6 RH
GND 2
5 RW
SCL 3
4 SDA
Ordering Information
PART NUMBER
(See Notes 1, 2)
PART MARKING
RTOTAL (kΩ)
TEMP RANGE
(°C)
PACKAGE
(Pb-Free)
PKG. DWG. #
ISL90727WIE627Z-TK
ANH
10
-40 to +85
6 Ld SC-70
P6.049
ISL90727UIE627Z-TK
ANI
50
-40 to +85
6 Ld SC-70
P6.049
ISL90728WIE627Z-TK
CCF
10
-40 to +85
6 Ld SC-70
P6.049
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. ISL90727 has an I2C address 5Ch and ISL90728 has an I2C address 7Ch
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) is a registered trademark of Intersil Americas Inc.
XDCP is a trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2005-2006. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
ISL90727, ISL90728
Pin Descriptions
PIN NUMBER
SYMBOL
DESCRIPTION
1
VDD
Supply Voltage
2
GND
Ground
3
SCL
Open drain Serial Clock input
4
SDA
Open drain Serial Data I/O
5
RW
Potentiometer Wiper Terminal
6
RH
Potentiometer High Terminal
Block Diagram
VDD
SCL
SDA
RH
I2C
INTERFACE
RW
WIPER
REGISTER
RL
GND
2
FN8247.4
August 2, 2006
ISL90727, ISL90728
Absolute Maximum Ratings
Recommended Operating Conditions
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C
Voltage at any Digital Interface Pin
with Respect to VSS . . . . . . . . . . . . . . . . . . . . . . -0.3V to VCC+0.3
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to +7V
Voltage at any DCP Pin with
Respect to VSS . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to VCC
Lead Temperature (soldering, 10s) . . . . . . . . . . . . . . . . . . . . . 300°C
IW (10s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ±6mA
Latchup . . . . . . . . . . . . . . . . . . . . . . . . . . . Class II, Level B at 85°C
ESD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . >2kV Human Body Model
Industrial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-40°C to +85°C
VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.7V to 5.5V
Power Rating of Each DCP . . . . . . . . . . . . . . . . . . . . . . . . . . . .5mW
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Analog Specifications
SYMBOL
RTOTAL
Over recommended operating conditions unless otherwise stated.
PARAMETER
RH to RL Resistance
TEST CONDITIONS
MIN
CH/CL/CW
ILkgDCP
Wiper Resistance
UNIT
10
kΩ
U option
50
kΩ
-20
VCC = 3.3V @ 25°C
85
Potentiometer Capacitance
Leakage on DCP Pins
MAX
W option
RH to RL Resistance Tolerance
RW
TYP
(Note 3)
Voltage at pin from GND to VCC
+20
%
200
Ω
10/10/
25
pF
0.1
µA
VOLTAGE DIVIDER MODE
INL
Integral Non-linearity
DNL
Differential Non-linearity
ZSerror
(Note 5)
Zero-scale Error
FSerror
(Note 6)
Full-scale Error
TCV (Note 12) Ratiometric Temperature Coefficient
-1
±0.2
1
LSB
(Note 4)
W option
-1
±0.1
1
LSB
(Note 4)
U option
-1
±0.1
1
LSB
(Note 4)
W option
0
1
3
U option
0
0.5
1
LSB
(Note 4)
W option
-3
-1
0
U option
-1
-0.5
0
Monotonic over all tap positions
DCP Register set to 80 hex
±15
LSB
(Note 4)
ppm/°C
RESISTOR MODE
RINL
(Note 10)
Integral Non-linearity
DCP register set between 20 hex and FF hex.
Monotonic over all tap positions
RDNL
(Note 9)
Differential Non-linearity
DCP register set between 20 hex
and FF hex. Monotonic over all tap
positions
Roffset
(Note 8)
Offset
TCR
Resistance Temperature Coefficient
(Notes 11, 12)
3
-2
±0.25
2
MI
(Note 7)
W option
-1
±0.1
1
MI
(Note 7)
U option
-1
±0.1
1
MI
(Note 7)
W option
0
1
3
MI
(Note 7)
U option
0
0.5
1
MI
(Note 7)
DCP register set between 20 hex and FF hex
±45
ppm/°C
FN8247.4
August 2, 2006
ISL90727, ISL90728
Operating Specifications
SYMBOL
ICC1
ISB
IComLkg
PARAMETER
TEST CONDITIONS
MIN
TYP
(Note 3)
MAX
UNIT
VCC Supply Current
(Volatile write/read)
fSCL = 400kHz; SDA = Open; (for I2C, Active,
Read and Volatile Write States only)
200
µA
VCC Current (standby)
VCC = +5.5V, I2C Interface in Standby State
500
nA
Common-Mode Leakage
Voltage at SDA pin to GND or VCC
3
µA
tDCP (Note 12) DCP Wiper Response Time
VCCRamp
VCC Ramp Rate
tD
Power-up Delay
SCL falling edge of last bit of DCP Data Byte to
wiper change
500
ns
0.2
VCC above Vpor, to DCP Initial Value Register
recall completed, and I2C Interface in standby state
V/ms
3
ms
SERIAL INTERFACE SPECIFICATIONS
VIL
SDA, and SCL Input Buffer LOW
Voltage
-0.3
0.3*
VCC
V
VIH
SDA, and SCL Input Buffer HIGH
Voltage
0.7*
VCC
VCC+
0.3
V
SDA and SCL Input Buffer Hysteresis
0.05*
VCC
Hysteresis
VOL
SDA Output Buffer LOW Voltage,
Sinking 4mA
0
Cpin (Note 14) SDA, and SCL Pin Capacitance
fSCL
SCL Frequency
tIN
Pulse Width Suppression Time at
SDA and SCL Inputs
tAA
SCL Falling Edge to SDA Output Data SCL falling edge crossing 30% of VCC, until SDA
Valid
exits the 30% to 70% of VCC window.
Any pulse narrower than the max spec is
suppressed.
V
0.4
V
10
pF
400
kHz
50
ns
900
ns
tBUF
Time the Bus Must be Free Before the SDA crossing 70% of VCC during a STOP
Start of a New Transmission
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.
600
ns
Output Data Hold Time
From SCL falling edge crossing 30% of VCC,
until SDA enters the 30% to 70% of VCC window.
0
ns
SDA and SCL Rise Time
From 30% to 70% of VCC
tDH
tR (Note 14)
4
20 +
0.1 * Cb
250
ns
FN8247.4
August 2, 2006
ISL90727, ISL90728
Operating Specifications
SYMBOL
(Continued)
PARAMETER
TEST CONDITIONS
MIN
TYP
(Note 3)
MAX
UNIT
tF (Note 14)
SDA and SCL Fall Time
From 70% to 30% of VCC
20 +
0.1 * Cb
250
ns
Cb (Note 14)
Capacitive Loading of SDA or SCL
Total on-chip and off-chip
10
400
pF
Maximum is determined by tR and tF.
For Cb = 400pF, max is about 2~2.5kΩ.
For Cb = 40pF, max is about 15~20kΩ
1
Rpu (Note 14) SDA and SCL Bus Pull-up Resistor
Off-chip
kΩ
SDA vs SCL Timing
tHIGH
tF
SCL
tLOW
tR
tSU:DAT
tSU:STA
tHD:DAT
tSU:STO
tHD:STA
SDA
(INPUT TIMING)
tAA
tDH
tBUF
SDA
(OUTPUT TIMING)
NOTES:
3. Typical values are for TA = 25°C and 3.3V supply voltage.
4. LSB: [V(RW)127 – V(RW)0]/127. V(RW)127 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.
5. ZS error = V(RW)0/LSB.
6. FS error = [V(RW)127 – VCC]/LSB.
7. MI = |R127 – R0|/127. R127 and R0 are the measured resistances for the DCP register set to FF hex and 00 hex respectively.
Roffset = R0/MI, when measuring between RW and RL.
8. Roffset = R127/MI, when measuring between RW and RH.
9. RDNL = (Ri – Ri-1)/MI - 1, for i = 32 to 127.
10. RINL = [Ri – (MI • i) – R0]/MI, for i = 32 to 127.
6
[ Max ( Ri ) – Min ( Ri ) ]
10
11. TC R = ---------------------------------------------------------------- × ----------------- for i = 32 to 127, T = -40°C to 85°C. Max( ) is the maximum value of the resistance and Min ( ) is the
[ Max ( Ri ) + Min ( Ri ) ] ⁄ 2 125°C minimum value of the resistance over the temperature range.
12. This parameter is not 100% tested.
13. VIL = 0V, VIH = VCC.
14. These are I2C-specific parameters and are not directly tested. However, they are used in the device testing to validate specifications.
Principles of Operation
The ISL90727 and ISL90728 are integrated circuits
incorporating one DCP with its associated registers and an
I2C serial interface providing direct communication between
a host and the potentiometer.
DCP Description
The DCP is implemented with a combination of resistor
elements and CMOS switches. The physical ends of the 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 a 7-bit volatile
Wiper Register (WR). The DCP has its own WR. When the WR
of the DCP contains all zeroes (WR<6:0> = 00h), its wiper
5
terminal (RW) is closest to its “Low” terminal (RL). When the
WR of the DCP contains all ones (WR<6:0> = 7Fh), its wiper
terminal (RW) is closest to its “High” terminal (RH). As the value
of the WR increases from all zeroes (00h) to all ones (127
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. RL is connected to the GND pin of the device, so
the wiper movement will always be relative to RL.
While the ISL90727 and ISL90728 are being powered up,
the WR is reset to 40h (64 decimal), which locates RW
roughly at the center between RL and RH.
FN8247.4
August 2, 2006
ISL90727, ISL90728
The WR and IVR can be read or written directly using the
I2C serial interface as described in the following sections.
I2C Serial Interface
The ISL90727 and ISL90728 support 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
ISL90727 and ISL90728 operate as slave devices 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 can change only during SCL
LOW periods. SDA state changes during SCL HIGH are
reserved for indicating START and STOP conditions (See
Figure 1). On power-up of the ISL90727 and ISL90728, the
SDA pin is in the input mode.
All I2C interface operations must begin with a START condition,
which is a HIGH to LOW transition of SDA while SCL is HIGH.
The ISL90727 and ISL90728 continuously monitor the SDA
and SCL lines for the START condition and do not respond to
any command until this condition is met (See Figure 1). A
START condition is ignored during the power-up sequence and
during internal non-volatile write cycles.
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 1).
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 2).
.
TABLE 1. IDENTIFICATION BYTE FORMAT
ISL90727
0
1
0
1
1
1
0
R/W
ISL90728
0
1
1
1
1
1
0
R/W
MSB
LSB
Write 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
ISL90727 and ISL90728 respond with an ACK. At this time,
the device enters its standby state (See Figure 3).
Data Protection
A valid Identification Byte, Address Byte, and total number of
SCL pulses act as a protection of both volatile and
non-volatile registers. During a Write sequence, the Data
Byte is loaded into an internal shift register as it is received.
If the Address Byte is 0, the Data Byte is transferred to the
Wiper Register (WR) at the falling edge of the SCL pulse
that loads the last bit (LSB) of the Data Byte. If an address
other than 00h or an invalid slave address is sent, then the
device will respond with no ACK.
Read Operation
A Read operation consist of a three byte instruction followed
by one or more Data Bytes (See Figure 4). 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 ISL90727 and ISL90728 respond with an ACK. Then the
ISL90727 and ISL90728 transmit the Data Byte as long as
the master responds with an ACK during the SCL cycle
following the eighth bit of each byte. The master then
terminates the read operation (issuing a STOP condition)
following the last bit of the Data Byte (See Figure 4).
The ISL90727 and ISL90728 respond 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 ISL90727 and ISL90728 also respond
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 0101110 as the seven
MSBs for the ISL90727 and 0111110 as the seven MSBs for
the ISL90728. The LSB in the Read/Write bit. Its value is “1”
for a Read operation, and “0” for a Write operation (See
Table 1)
6
FN8247.4
August 2, 2006
ISL90727, ISL90728
SCL
SDA
START
DATA
STABLE
DATA
CHANGE
DATA
STABLE
STOP
FIGURE 1. VALID DATA CHANGES, START AND STOP CONDITIONS
SCL FROM
MASTER
1
8
9
SDA OUTPUT FROM
TRANSMITTER
HIGH IMPEDANCE
HIGH IMPEDANCE
SDA OUTPUT FROM
RECEIVER
START
ACK
FIGURE 2. ACKNOWLEDGE RESPONSE FROM RECEIVER
WRITE
SIGNALS FROM
THE MASTER
SIGNAL AT SDA
S
T
A
R
T
IDENTIFICATION
BYTE
ADDRESS
BYTE
0 1 0 1 1 1 0 0
0 0 0 0 0 0 0 0
SIGNALS FROM
THE ISL23711
A
C
K
A
C
K
A
C
K
S
T
O
P
DATA
BYTE
FIGURE 3. BYTE WRITE SEQUENCE (ISL90727 VERSION SHOWN)
S
T
A
R
T
SIGNALS
FROM THE
MASTER
SIGNAL AT SDA
SIGNALS FROM
THE SLAVE
IDENTIFICATION
BYTE WITH
R/W=0
S
T
A IDENTIFICATION
R
BYTE WITH
T
R/W=1
ADDRESS
BYTE
0 1 0 1 1 1 0 0
0 1 0 1 1 1 0 1
0 0 0 0 0 0 0 0
A
C
K
S
T
O
P
A
C
K
A
C
K
DATA BYTE
FIGURE 4. READ SEQUENCE (ISL90727 VERSION SHOWN)
7
FN8247.4
August 2, 2006
ISL90727, ISL90728
Small Outline Transistor Plastic Packages (SC70-6)
0.20 (0.008) M
P6.049
VIEW C
C
6 LEAD SMALL OUTLINE TRANSISTOR PLASTIC PACKAGE
CL
INCHES
e
b
SYMBOL
6
5
4
CL
CL
E1
E
1
2
3
e1
C
D
CL
A
A2
SEATING
PLANE
A1
-C-
WITH
b
PLATING
b1
c
c1
MILLIMETERS
MAX
MIN
MAX
NOTES
A
0.031
0.043
0.80
1.10
-
A1
0.000
0.004
0.00
0.10
-
A2
0.031
0.039
0.00
1.00
-
b
0.006
0.012
0.15
0.30
-
b1
0.006
0.010
0.15
0.25
c
0.003
0.009
0.08
0.22
6
c1
0.003
0.009
0.08
0.20
6
D
0.073
0.085
1.85
2.15
3
E
0.071
0.094
1.80
2.40
-
E1
0.045
0.053
1.15
1.35
3
e
0.0256 Ref
0.65 Ref
-
e1
0.0512 Ref
1.30 Ref
-
L
0.10 (0.004) C
MIN
0.010
0.018
0.26
0.46
L1
0.017 Ref.
0.420 Ref.
L2
0.006 BSC
0.15 BSC
N
6
6
4
5
R
0.004
-
0.10
-
R1
0.004
0.010
0.15
0.25
α
0o
8o
0o
8o
Rev. 2 9/03
NOTES:
BASE METAL
1. Dimensioning and tolerance per ASME Y14.5M-1994.
2. Package conforms to EIAJ SC70 and JEDEC MO203AB.
4X θ1
3. Dimensions D and E1 are exclusive of mold flash, protrusions,
or gate burrs.
R1
4. Footlength L measured at reference to gauge plane.
5. “N” is the number of terminal positions.
R
GAUGE PLANE
SEATING
PLANE
L
C
L1
α
L2
6. These Dimensions apply to the flat section of the lead between
0.08mm and 0.15mm from the lead tip.
7. Controlling dimension: MILLIMETER. Converted inch dimensions are for reference only
4X θ1
VIEW C
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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.
For information regarding Intersil Corporation and its products, see www.intersil.com
8
FN8247.4
August 2, 2006
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