INTERSIL ISL90727

ISL90727
®
Single Volatile 128-Tap XDCP
Data Sheet
PRELIMINARY
August 1, 2005
Digitally Controlled Potentiometer
(XDCP™)
Features
The Intersil ISL90727 is a digitally controlled potentiometer
(XDCP). The 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
• 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.
The device can be used in a wide variety of applications
including:
• Mechanical potentiometer replacement
• Transducer adjustment of pressure, temperature, position,
chemical, and optical sensors
• DCP Terminal Voltage, 2.7V to 5.5V
• Low Tempco
- Rheostat - 45 ppm/°C typical @ 25°C
- Divider - 15 ppm/°C typical @ 25°C
• 128 Wiper Tap Points
- Wiper resistance 70Ω typ at VCC = 3.3V
• Low Power CMOS
- Active current, 200µA max
- Standby current, 500nA max
• Available RTOTAL Values = 50kΩ, 10kΩ
• Power on Preset to Midscale
• Direct replacement for AD5247
• RF amplifier biasing
• Packaging
- 6 Ld SC70
• LCD brightness and contrast adjustment
• Gain control and offset adjustment
• Pb-free plus anneal available (RoHS compliant)
Ordering Information
Pinout
RESISTANCE
OPTION (Ω)
TEMP
RANGE
(°C)
PACKAGE
(Pb-Free)
ISL90727WIE6Z
10K
-40 to +85
6-Pin SC-70
ISL90727UIE6Z
50K
-40 to +85
6-Pin SC-70
ISL90727WIE6Z-TK
10K
-40 to +85
ISL90727UIE6Z-TK
50K
-40 to +85
PART NUMBER
(See Note)
FN8247.1
ISL90727
(6-PIN SC70)
TOP VIEW
VDD 1
6 RH
6-Pin SC-70
GND 2
5 RW
6-Pin SC-70
SCL 3
4 SDA
NOTE: 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.
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143 | 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.
ISL90727
Pin Descriptions
PIN NUMBER
SYMBOL
DESCRIPTION
1
VDD
Supply Voltage
2
GND
Ground
3
SCL
Serial Clock
4
SDA
Serial Data
5
RW
Potentiometer Wiper Terminal
6
RH
Potentiometer High Terminal
Block Diagram
VDD
SCL
SDA
RH
I2C
INTERFACE
RW
WIPER
REGISTER
RL
GND
2
FN8247.1
August 1, 2005
ISL90727
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
W, U versions respectively
CH/CL/CW
(Note 10)
ILkgDCP
Wiper resistance
-20
VCC = 3.3V @ 25°C
85
Potentiometer Capacitance
Leakage on DCP pins (Note 10)
MAX
10, 50
RH to RL resistance tolerance
RW
TYP
(Note 1)
Voltage at pin from GND to VCC
UNIT
kΩ
+20
%
200
Ω
10/10/
25
pF
0.1
µA
VOLTAGE DIVIDER MODE
INL
Integral non-linearity
DNL
Differential non-linearity
ZSerror
(Note 3)
Zero-scale error
FSerror
(Note 4)
Full-scale error
TCV (Note 10) Ratiometric Temperature Coefficient
-1
±0.2
1
LSB
(Note 2)
W option
-1
±0.1
1
LSB
(Note 2)
U option
-1
±0.1
1
LSB
(Note 2)
W option
0
1
3
U option
0
0.5
1
LSB
(Note 2)
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 2)
ppm/°C
RESISTOR MODE
RINL
(Note 8)
Integral non-linearity
RDNL (Note 7) Differential non-linearity
Roffset
(Note 6)
TCR
(Notes 9, 10)
Offset
Resistance Temperature Coefficient
3
DCP register set between 20 hex and FF hex.
Monotonic over all tap positions
-2
±0.25
2
MI
(Note 5)
W option
-1
±0.1
1
MI
(Note 5)
U option
-1
±0.1
1
MI
(Note 5)
W option
0
1
3
MI
(Note 5)
U option
0
0.5
1
MI
(Note 5)
DCP register set between 20 hex
and FF hex. Monotonic over all tap
positions
DCP register set between 20 hex and FF hex
±45
ppm/°C
FN8247.1
August 1, 2005
ISL90727
Operating Specifications
SYMBOL
PARAMETER
TEST CONDITIONS
MIN
TYP
(Note 1)
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
IComLkg
Common-Mode Leakage
Voltage at SDA pin to GND or VCC
3
µA
tDCP (Note 10)
DCP wiper response time
SCL falling edge of last bit of DCP Data Byte to
wiper change
ICC1
ISB
VCCRamp
VCC ramp rate
tD
Power-up delay
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
Cpin (Note 12)
fSCL
0
V
0.4
V
SDA, and SCL pin capacitance
10
pF
SCL frequency
400
kHz
tIN
Pulse width suppression time at
SDA and SCL inputs
Any pulse narrower than the max spec is
suppressed.
50
ns
tAA
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
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.
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 12)
4
20 +
0.1 * Cb
250
ns
FN8247.1
August 1, 2005
ISL90727
Operating Specifications
SYMBOL
(Continued)
PARAMETER
TEST CONDITIONS
MIN
From 70% to 30% of VCC
TYP
(Note 1)
MAX
UNIT
20 +
0.1 * Cb
250
ns
400
pF
tF (Note 12)
SDA and SCL fall time
Cb (Note 12)
Capacitive loading of SDA or SCL Total on-chip and off-chip
10
Rpu (Note 12)
SDA and SCL bus pull-up resistor Maximum is determined by tR and tF.
off-chip
For Cb = 400pF, max is about 2~2.5kΩ.
For Cb = 40pF, max is about 15~20kΩ
1
kΩ
SDA vs SCL Timing
tHIGH
tF
SCL
tLOW
tR
tSU:DAT
tSU:STA
SDA
(INPUT TIMING)
tHD:DAT
tHD:STA
tSU:STO
tAA
tDH
tBUF
SDA
(OUTPUT TIMING)
NOTES:
1. Typical values are for TA = 25°C and 3.3V supply voltage.
2. 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.
3. ZS error = V(RW)0/LSB.
4. FS error = [V(RW)127 – VCC]/LSB.
5. 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.
6. Roffset = R127/MI, when measuring between RW and RH.
7. RDNL = (Ri – Ri-1)/MI, for i = 32 to 127.
8. RINL = [Ri – (MI • i) – R0]/MI, for i = 32 to 127.
6
[ Max ( Ri ) – Min ( Ri ) ]
10
9. 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.
10. This parameter is not 100% tested.
11. VIL = 0V, VIH = VCC.
12. 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 is an integrated circuit 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>=
5
00h), its wiper 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 is being powered up, the WR is reset to
20h (64 decimal), which locates RW roughly at the center
between RL and RH.
FN8247.1
August 1, 2005
ISL90727
The WR and IVR can be read or written directly using the
I2C serial interface as described in the following sections.
Byte of a write operation. The master must respond with an
ACK after receiving a Data Byte of a read operation.
I2C Serial Interface
A valid Identification Byte contains 0101000 as the seven
MSBs. The LSB in the Read/Write bit. Its value is “1” for a
Read operation, and “0” for a Write operation (See Table 1).
The ISL90727 supports 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
operates as 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 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, 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 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 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).
The ISL90727 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
ISL90727 also responds with an ACK after receiving a Data
TABLE 1. IDENTIFICATION BYTE FORMAT
0
1
0
1
0
(MSB)
0
0
R/W
(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 responds 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 nonvolatile 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 responds with an ACK. Then the ISL90727
transmits 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).
SCL
SDA
START
DATA
STABLE
DATA
CHANGE
DATA
STABLE
STOP
FIGURE 1. VALID DATA CHANGES, START, AND STOP CONDITIONS
6
FN8247.1
August 1, 2005
ISL90727
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 0 0 0 0
0 0 0 0 0 0 0 0
SIGNALS FROM
THE ISL23711
A
C
K
A
C
K
S
T
O
P
DATA
BYTE
A
C
K
FIGURE 3. BYTE WRITE SEQUENCE
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 0 0 0 0
0 1 0 1 0 0 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
7
FN8247.1
August 1, 2005
ISL90727
Small Outline Transistor Plastic Packages (SC70-6)
0.20 (0.008) M
SC70-6
VIEW C
C
6 LEAD SMALL OUTLINE TRANSISTOR PLASTIC PACKAGE
CL
INCHES
e
b
6
5
4
CL
CL
E1
E
1
2
3
e1
C
D
CL
A
A2
SEATING
PLANE
A1
-C-
SYMBOL
MIN
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
0.071
0.087
1.80
2.20
3
E
0.071
0.094
1.80
2.40
-
E1
0.045
0.053
1.15
1.35
3
e
e1
L
0.10 (0.004) C
WITH
b
PLATING
b1
0.0256 Ref
c1
0.65 Ref
0.0512 Ref
0.010
0.018
-
1.30 Ref
0.26
-
0.46
L1
0.017 Ref.
0.420 Ref.
L2
0.006 BSC
0.15 BSC
N
c
MILLIMETERS
6
4
6
5
R
0.004
-
0.10
-
R1
0.004
0.010
0.15
0.25
α
0°
8°
0°
8°
-
NOTES:
BASE METAL
1. Dimensioning and tolerance per ASME Y14.5M-1994.
2. Package conforms to EIAJ SC70 and JEDEC MO203AB.
3. Dimensions D and E1 are exclusive of mold flash, protrusions, or
gate burrs.
4X θ1
4. Footlength L measured at reference to gauge plane.
R1
5. “N” is the number of terminal positions.
R
GAUGE PLANE
SEATING
PLANE
L
C
L1
α
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.
L2
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
FN8247.1
August 1, 2005