LINER LTC1663IMS8

LTC1663
10-Bit Rail-to-Rail
Micropower DAC with 2-Wire Interface
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DESCRIPTIO
FEATURES
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The LTC®1663 is a 10-bit voltage output DAC with true
buffered rail-to-rail output voltage capability. It operates
from a single supply with a range of 2.7V to 5.5V. The
reference for the DAC is selectable between the supply
voltage or an internal bandgap reference. Selecting the
internal bandgap reference will set the full-scale output
voltage range to 2.5V. Selecting the supply as the reference sets the output voltage range to the supply voltage.
Micropower 10-Bit DAC in SOT-23
Low Operating Current: 60µA
Ultralow Power Shutdown Mode: 10µA
2-Wire Serial Interface Compatible
with SMBus and I2CTM
Single 2.7V to 5.5V Operation
Selectable Internal Reference or Ratiometric to VCC
Buffered True Rail-to-Rail Voltage Output
Maximum DNL Error: 0.75LSB
Power-On Reset
8 User Selectable Addresses (MSOP Package)
0.6V VIL and 1.4V VIH for SDA and SCL
Small 5-Lead SOT-23 and 8-Lead MSOP Packages
The part features a simple 2-wire serial interface compatible with SMBus and I2C that allows communication
between many devices. The internal data registers are
double buffered to allow for simultaneous update of
several devices at once. The DAC can be put in low current
power-down mode for use in power conscious systems.
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APPLICATIO S
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Power-on reset ensures the DAC output is at 0V when
power is initially applied, and all internal registers are
cleared.
Digital Calibration
Offset/Gain Adjustment
Industrial Process Control
Automatic Test Equipment
Arbitrary Function Generators
Battery-Powered Data Conversion Products
, LTC and LT are registered trademarks of Linear Technology Corporation.
I2C is a trademark of Philips Electronics N.V.
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BLOCK DIAGRA
4 (5)
VCC
1.25V
BANDGAP
REFERENCE
Differential Nonlinearity (DNL)
1.0
VREF = VCC = 5V
TA = 25°C
0.8
REFERENCE
SELECT
0.6
10-BIT
DAC LATCH
+
VOUT 3 (8)
COMMAND
LATCH
– 0.6
R
INPUT
LATCH
– 0.8
R
–1.0
0
(6) AD0
(2) AD1
(3) AD2
0
– 0.2
– 0.4
–
MSOP
PACKAGE
ONLY
ERROR (LSB)
0.4
0.2
2-WIRE INTERFACE
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156 384 512 640 768 896 1024
CODE
1663 G02
SDA
SCL
GND
1 (1)
5 (4)
2 (7)
1663 BD
NOTE: PIN NUMBERS IN PARENTHESES REFER TO THE MSOP PACKAGE
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LTC1663
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ABSOLUTE
RATI GS
(Note 1)
VCC to GND .............................................. – 0.3V to 7.5V
SDA, SCL ..................................................– 0.3V to 7.5V
AD0, AD1, AD2 (MSOP Only) ...... – 0.3V to (VCC + 0.3V)
VOUT ............................................ – 0.3V to (VCC + 0.3V)
Operating Temperature Range
LTC1663C .............................................. 0°C to 70°C
LTC1663I ........................................... – 40°C to 85°C
Storage Temperature Range ................ – 65°C to 150°C
Lead Temperature (Soldering, 10 sec)................. 300°C
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PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
LTC1663CMS8
LTC1663IMS8
TOP VIEW
SDA
AD1
AD2
SCL
1
2
3
4
8
7
6
5
VOUT
GND
AD0
VCC
MS8 PACKAGE
8-LEAD PLASTIC MSOP
TJMAX = 125°C, θJA = 150°C/W
MS8 PART MARKING
LTEQ
LTJJ
ORDER PART
NUMBER
LTC1663CS5
TOP VIEW
SDA 1
5 SCL
GND 2
VOUT 3
4 VCC
S5 PART MARKING
LTEP
S5 PACKAGE
5-LEAD PLASTIC SOT-23
TJMAX = 125°C, θJA = 250°C/W
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 2.7V to 5.5V, VCC set as reference, VOUT unloaded,
unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
DAC
Resolution
●
10
Bits
Monotonicity
(Note 2)
●
10
Bits
DNL
Differential Nonlinearity
Guaranteed Monotonic (Note 2)
●
±0.2
±0.75
LSB
INL
Integral Nonlinearity
(Note 2)
●
±0.5
±2.5
LSB
VOS
Offset Error
Measured at Code 20
●
±10
±30
VOSTC
Offset Error Temperature Coefficient
FSE
Full-Scale Error
Reference Set to VCC
Reference Set to Internal Bandgap
VOUT
DAC Output Span
Reference Set to VCC
Reference Set to Internal Bandgap
0 to VCC
0 to 2.5
VFSTC
Full-Scale Voltage Temperature Coefficient
±30
µV/°C
PSRR
Power Supply Rejection Ratio
Reference Set to Internal Bandgap,
Code = 1023
±0.4
LSB/V
±15
±3
±3
●
●
mV
µV/°C
±15
±15
LSB
LSB
V
V
Power Supply
VCC
Positive Supply Voltage
5.5
V
ICC
Supply Current
VCC = 3V (Note 3)
VCC = 5V (Note 3)
●
●
60
75
100
125
µA
µA
ISD
Supply Current in Shutdown Mode
(Note 3)
●
10
16
µA
Short-Circuit Current (Sourcing)
Short-Circuit Current (Sinking)
VOUT Shorted to GND, Input Code = 1023
●
25
100
mA
VOUT Shorted to VCC, Input Code = 0
●
30
120
mA
Output Impedance to GND
Input Code = 0, VCC = 5V
Input Code = 0, VCC = 3V
In Shutdown Mode
●
2.7
Op Amp DC Performance
2
65
150
500
Ω
Ω
kΩ
LTC1663
ELECTRICAL CHARACTERISTICS
The ● denotes specifications which apply over the full operating
temperature range, otherwise specifications are at TA = 25°C. VCC = 2.7V to 5.5V, VCC set as reference, VOUT unloaded,
unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
Output Impedance to VCC
Input Code = 1023, VCC = 5V
Input Code = 1023, VCC = 3V
MIN
TYP
80
120
MAX
UNITS
Ω
Ω
Voltage Output Slew Rate
Rising (Notes 4, 5)
Falling (Notes 4, 5)
0.75
0.25
V/µs
V/µs
Voltage Output Settling Time
To ±0.5LSB (Notes 4, 5)
AC Performance
Digital Feedthrough
Digital-to-Analog Glitch Impulse
µs
30
1LSB Change Around Major Carry
0.75
nV • s
70
nV • s
Digital Inputs SCL, SDA
VIH
High Level Input Voltage
●
1.4
V
VIL
Low Level Input Voltage
●
VLTH
Logic Threshold Voltage
ILEAK
Digital Input Leakage
VCC = 5.5V and 0V, VIN = GND to VCC
●
±1
µA
CIN
Digital Input Capacitance
(Note 7)
●
10
pF
IPULLUP = 350µA
●
0.4
V
VIN = 0V
●
1.5
µA
0.6
V
1
V
Digital Output SDA
VOL
Digital Output Low Voltage
Address Inputs AD0, AD1, AD2 (MSOP Only)
IUP
Address Pin Pull-Up Current
VIH
High Level Input Voltage
● VCC – 0.3
0.5
VIL
Low Level Input Voltage
●
V
0.8
V
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TI I G CHARACTERISTICS
The ● denotes specifications which apply over the full operating temperature
range, otherwise specifications are at TA = 25°C. VCC = 2.7V to 5.5V, VCC set as reference, VOUT unloaded, unless otherwise noted.
SYMBOL
PARAMETER
MIN
TYP
MAX
UNITS
100
kHz
SMBus Timing Characteristics (Notes 6, 7)
fSMB
SMBus Operating Frequency
●
10
tBUF
Bus Free Time Between Stop and Start Condition
●
4.7
µs
tHD, STA
Hold Time After (Repeated) Start Condition
●
4.0
µs
tSU, STA
Repeated Start Condition Setup Time
●
4.7
µs
tSU, STO
Stop Condition Setup Time
●
4.0
µs
tHD, DAT
Data Hold Time
●
300
ns
tSU, DAT
Data Setup Time
●
250
ns
tLOW
Clock Low Period
●
4.7
tHIGH
Clock High Period
●
4.0
tf
Clock, Data Fall Time
tr
Clock, Data Rise Time
Note 1: Absolute maximum ratings are those values beyond which the life
of a device may be impaired.
Note 2: Nonlinearity and monotonicity are defined from code 20 to code
1003 (full scale). See Applications Information.
Note 3: Digital inputs at 0V or VCC.
µs
50
µs
●
300
ns
●
1000
ns
Note 4: Load is 10kΩ in parallel with 100pF.
Note 5: VCC = VREF = 5V. DAC switched between 0.1VFS and 0.9VFS,
i.e., codes k = 102 and k = 922.
Note 6: All values are referenced to VIH and VIL levels.
Note 7: Guaranteed by design and not subject to test.
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LTC1663
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TYPICAL PERFOR A CE CHARACTERISTICS
Integral Nonlinearity (INL)
1.0
1.0
VREF = VCC = 5V
TA = 25°C
5.0
VREF = VCC = 5V
TA = 25°C
0.8
0.6
0.4
0.4
ERROR (LSB)
0.6
0.2
0
– 0.2
0.2
0
– 0.2
3.5
3.0
2.5
2.0
– 0.4
– 0.6
– 0.6
1.0
– 0.8
– 0.8
0.5
1.5
–1.0
0
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CODE
DAC CODE = 1023
4.0
– 0.4
–1.0
TA = 25°C
4.5
OUTPUT VOLTAGE (V)
0.8
ERROR (LSB)
Source and Sink Current
Capability with VCC = 5V
Differential Nonlinearity (DNL)
0
28
0
156 384 512 640 768 896 1024
CODE
1663 G01
DAC CODE = 0
1 2 3 4 5 6 7 8 9 10
OUTPUT CURRENT SOURCE/SINK (mA)
0
1663 G02
Large-Signal Step Response
1011 G03
Midscale Glitch
Load Regulation vs Output Current
1.0
5
SDA
(VOLTS) 0
0.8
5V
SDA
0V
5
0.6
0.4
CODE = 512 TO 511
∆VOUT (LSB)
CODE = 990
4
VCC = 5V
RL = 4.7k
CL = 100pF
TA = 25°C
3
VOUT
(VOLTS) 2
VOUT
10mV/DIV
0
SOURCE
– 0.4
VCC = 5V
RL = 4.7k
CL = 100pF
TA = 25°C
CODE = 32
0
2µs/DIV
1663 G04
0.2
– 0.2
1
5µs/DIV
VCC = VREF = 5V
VOUT = 2.5V
CODE = 512
TA = 25°C
SINK
– 0.6
– 0.8
–1.0
–4
1663 G05
–3
–2
–1 0
1
IOUT (mA)
3
2
4
1663 G06
Offset Error Voltage vs
Temperature
Load Regulation vs Output Current
0.6
OFFSET ERROR VOLTAGE (mV)
0.8
VCC = VREF = 3V
VOUT = 1.5V
CODE = 512
TA = 25°C
∆VOUT (LSB)
0.4
0.2
0
– 0.2
– 0.4
SOURCE
SINK
– 0.6
5
2.510
4
2.508
3
2.506
OUTPUT VOLTAGE (V)
1.0
Full-Scale Output Voltage vs
Temperature
2
1
0
–1
–2
2.504
2.502
2.500
2.498
2.496
–3
2.494
– 0.8
–4
2.492
–1.0
–1.0 – 0.8– 0.6– 0.4– 0.2 0 0.2 0.4 0.6 0.8 1.0
IOUT (mA)
–5
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
1663 G07
4
80
100
1663 G08
REFERENCE SET TO
INTERNAL BANDGAP
2.490
–60 –40 –20 0 20 40 60
TEMPERATURE (°C)
80
100
1663 G09
LTC1663
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PIN FUNCTIONS
SDA (Pin 1, Pin 1 on SOT-23): Serial Data Bidirectional
Pin. Data is shifted into the SDA pin and acknowledged by
the SDA pin. High impedance pin while data is shifted in.
Open-drain N-channel output during acknowledgment.
Requires a pull-up resistor or current source to VCC.
AD1 (Pin 2): Slave Address Select Bit 1. Tie this pin to
either VCC or GND to modify the corresponding bit of the
LTC1663’s slave address.
AD2 (Pin 3): Slave Address Select Bit 2. Tie this pin to
either VCC or GND to modify the corresponding bit of the
LTC1663’s slave address.
VCC (Pin 5, Pin 4 on SOT-23): Power Supply. 2.7V ≤ VCC
≤ 5.5V. Also used as the reference voltage input when the
part is programmed to use VCC as the reference.
AD0 (Pin 6): Slave Address Select Bit 0. Tie this pin to
either VCC or GND to modify the corresponding bit of the
LTC1663’s slave address.
GND (Pin 7, Pin 2 on SOT-23): System Ground.
VOUT (Pin 8, Pin 3 on SOT-23): Voltage Output. Buffered
rail-to-rail DAC output.
SCL (Pin 4, Pin 5 on SOT-23): Serial Clock Input Pin. Data
is shifted into the SDA pin at the rising edges of the clock.
This high impedance pin requires a pull-up resistor or
current source to VCC.
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DEFINITIONS
Differential Nonlinearity (DNL): The difference between
the measured change and the ideal 1LSB change for any
two adjacent codes. The DNL error between any two codes
is calculated as follows:
DNL = (∆VOUT – LSB)/LSB
Where ∆VOUT is the measured voltage difference between
two adjacent codes.
Digital Feedthrough: The glitch that appears at the analog
output caused by AC coupling from the digital inputs when
they change state. The area of the glitch is specified in
(nV)(sec).
Full-Scale Error (FSE): The deviation of the actual fullscale voltage from ideal. FSE includes the effects of offset
and gain errors (see Applications Information).
Integral Nonlinearity (INL): The deviation from a straight
line passing through the endpoints of the DAC transfer
curve (Endpoint INL). Because the output cannot go below
zero, the linearity is measured between full scale and the
lowest code that guarantees the output will be greater than
zero. The INL error at a given input code is calculated as
follows:
INL = [VOUT – VOS – (VFS – VOS)(code/1023)]/LSB
Where VOUT is the output voltage of the DAC measured at
the given input code.
Least Significant Bit (LSB): The ideal voltage difference
between two successive codes.
LSB = VREF/1024
Resolution (n): Defines the number of DAC output states
(2n) that divide the full-scale range. Resolution does not
imply linearity.
Voltage Offset Error (VOS): Nominally, the voltage at the
output when the DAC is loaded with all zeros. A single
supply DAC can have a true negative offset, but the output
cannot go below zero (see Applications Information).
For this reason, single supply DAC offset is measured at
the lowest code that guarantees the output will be greater
than zero.
5
6
NOTE: X = DON’T CARE
2
1
SCL
VOUT
1
0
START
SDA
3
0
5
1
ADDRESS
4
0
6
1
7
1
8
0
tLOW
tr
tHIGH
tf
tSU, DAT
tHD, DAT
REPEATED START
CONDITION
tSU, STA
tHD, STA
STOP
CONDITION
9
ACK
1
X
2
X
3
X
5
X
COMMAND
4
X
6
0
7
0
8
0
9
ACK
1
1
2
1
3
1
4
1
LS DATA
5
1
6
1
7
1
8
1
9
ACK
1
X
2
X
3
X
4
X
tBUF
tSU, STO
Typical Input Waveform—Programming DAC Output for Full Scale (AD2 to AD0 Set High)
START
CONDITION
tHD, STA
SCL
SDA
6
X
MS DATA
5
X
START
CONDITION
1663 TD
7
1
8
1
9
ACK
STOP
1663 TA02
ZERO-SCALE
VOLTAGE
FULL-SCALE
VOLTAGE
LTC1663
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TI I G DIAGRA
LTC1663
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APPLICATIONS INFORMATION
Write Word Protocol Used by the LTC1663
1
7
1
1
8
1
8
1
8
1
1
S
Slave Address
Wr
A
Command Byte
A
LSData Byte
A
MSData Byte
A
P
1663 TA03
S = Start Condition, Wr = Write Bit = 0, A = Acknowledge, P = Stop Condition
Serial Digital Interface
Write Word Protocol
The LTC1663 communicates with a host (master) using
the standard 2-wire interface. The Timing Diagram shows
the timing relationship of the signals on the bus. The two
bus lines, SDA and SCL, must be high when the bus is not
in use. External pull-up resistors or current sources, such
as the LTC1694 SMBus Accelerator, are required on these
lines.
The master initiates communication with the LTC1663
with a START condition and a 7-bit address followed by the
Write Bit (Wr) = 0. The LTC1663 acknowledges and the
master delivers the command byte. The LTC1663 acknowledges and latches the command byte into the command byte input register. The master then delivers the
least significant data byte. Again the LTC1663 acknowledges and the data is latched into the least significant data
byte input register. The master then delivers the most
significant data byte. The LTC1663 acknowledges once
more and latches the data into the most significant data
byte input register. Lastly, the master terminates the
communication with a STOP condition. On the reception
of the STOP condition, the LTC1663 transfers the input
register information to output registers and the DAC
output is updated.
The LTC1663 is a receive-only (slave) device. The master
can communicate with the LTC1663 using the Quick
Command, Send Byte or Write Word protocols as explained later.
The START and STOP Conditions
When the bus is not in use, both SCL and SDA must be
high. A bus master signals the beginning of a communication to a slave device by transmitting a START condition.
A START condition is generated by transitioning SDA
from high to low while SCL is high.
When the master has finished communicating with the
slave, it issues a STOP condition. A STOP condition is
generated by transitioning SDA from low to high while SCL
is high. The bus is then free for communication with
another SMBus device.
Slave Address (MSOP Package Only)
The LTC1663 can respond to one of eight 7-bit addresses.
The first 4 bits (MSBs) have been factory programmed to
0100. The three address bits, AD2, AD1 and AD0 are
programmed by the user and determine the LSBs of the
slave address, as shown in the table below:
AD2
AD1
AD0
0100 xxx
Acknowledge
L
L
L
0100 000
The Acknowledge signal is used for handshaking between
the master and the slave. An Acknowledge (active LOW)
generated by the slave lets the master know that the latest
byte of information was received. The Acknowledge related clock pulse is generated by the master. The master
releases the SDA line (HIGH) during the Acknowledge
clock pulse. The slave-receiver must pull down the SDA
line during the Acknowledge clock pulse so that it remains
a stable LOW during the HIGH period of this clock pulse.
L
L
H
0100 001
L
H
L
0100 010
L
H
H
0100 011
H
L
L
0100 100
H
L
H
0100 101
H
H
L
0100 110
H
H
H
0100 111
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LTC1663
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APPLICATIONS INFORMATION
Slave Address (SOT-23 Package)
The slave address for the SOT-23 package has been
factory programmed to be “0100 000.” If another address
is required, please consult the factory.
Command Byte
The Bandgap (BG) bit when set to “0” selects the DAC
supply voltage as its voltage reference. The full-scale
output of the DAC with this setting is equal to the supply
voltage. When the BG bit is set to “1,” the internal bandgap
reference (≈1.25V) is selected as the DAC’s reference. The
full-scale output voltage for this setting is 2.5V.
7
6
5
4
3
2
1
0
Data Bytes
X
X
X
X
X
BG
SD
SY
Least Significant Data Byte
SY
1
0
Allows update on Acknowledge of SYNC Address only
Update on Stop condition only (Power-On Default)
SD
1
0
Puts the device in power-down mode
Puts the device in standard operating mode
(Power-On Default)
BG
X
1
0
Selects the internal bandgap reference
Selects the supply as the reference (Power-On Default)
X
Don’t Care
The stop condition normally initiates the update of the
DAC’s output latches. This allows for simultaneous update
of more than one DAC or other devices on the bus. This can
be overridden by setting the “SY” bit of the command byte.
Setting this bit sets the device to update the DAC output
latches at the reception of a SYNC address quick command. The actual update occurs on the rising edge of SCL
during the Acknowledge. In this way, all devices can
update on the reception of the SYNC address quick command instead of the STOP condition.
A Shutdown (SD) bit = HIGH will put the device in a low
power state but retain all data latch information. Shutdown
will occur at the reception of a STOP condition. This way
shutdown could be synchronized to other devices. The
output impedance of the DAC will go to a high impedance
state (≈ 500kΩ to GND).
8
7
6
5
4
3
2
1
0
D7
D6
D5
D4
D3
D2
D1
D0
Most Significant Data Byte
7
6
5
4
3
2
1
0
X
X
X
X
X
X
D9
D8
X = Don’t care
Send Byte Protocol
The Send Byte protocol used on the LTC1663 is actually a
subset of the Write Word protocol described previously.
The Send Byte protocol can only be used to send the
command byte information to the LTC1663.
1
7
1
1
8
1
1
S
Slave Address
Wr
A
Command Byte
A
P
S = Start Condition, Wr = Write Bit, A = Acknowledge, P = Stop Condition
1663 TA04
The Send Byte protocol is also used whenever the Write
Word protocol is interrupted for any reason. Reception of
a START or STOP condition after the Acknowledge of the
command byte, but before the Acknowledge of the last
data byte, will cause both data bytes to be ignored and the
command byte to be accepted.
Reception of a START or STOP condition before the
Acknowledge of the command byte will cause the interrupted command byte to be ignored.
LTC1663
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APPLICATIONS INFORMATION
SYNC Address/Quick Command
In addition to the slave address, the LTC1663 has an
address that can be shared by other devices so that they
may be updated synchronously. The address is called to
the SYNC address and uses the quick command protocol.
The SYNC Address is 1111 110
1
7
1
1
1
Start
1111 110
SY/CLR
Ack
Stop
SYNC Address
SY/CLR
1
0
1663 TA05
Update output latches on rising edge of SCL during
Acknowledge of SYNC Address
Clear all internal latches on rising edge of SCL during
Acknowledge of SYNC Address
The SY/CLR bit set high only has meaning when the “SY”
bit of the command byte was previously set HIGH. On the
otherhand, the SY/CLR bit set LOW will always clear the
part, independent of the state of the “SY” bit in the
command byte.
Input Threshold
Anticipating the trend toward lower supply voltages, the
SMBus is specified with a VIH of 1.4V and a VIL of 0.6V.
While some SMBus parts may violate this stringent SMBus
specification by allowing a higher VIH value for a correspondingly higher input supply voltage, the LTC1663
meets and maintains the constant SMBus input threshold
specification across the entire supply voltage range of
2.7V to 5.5V. The logic input threshold is designed to be
1V with 50mV of hysteresis.
Voltage Output
The output amplifier contained in the LTC1663 can source
or sink up to 5mA. The output stage swings to within a few
millivolts of either supply rail when unloaded and has an
equivalent output resistance of 85Ω when driving a load to
the rails. The output amplifier is stable driving capacitive
loads up to 1000pF.
A small resistor placed in series with the output can be
used to achieve stability for any load capacitance greater
than 1000pF. For example, a 0.1µF load can be driven by
the LTC1663 if a 110Ω series resistance is used. The phase
margin of the resulting circuit is 45° and increases monotonically from this point if larger values of resistance, capacitance or both are substituted for the values given.
Rail-to-Rail Output Considerations
As in any rail-to-rail device, the output is limited to
voltages within the supply range.
If the DAC offset is negative, the output for the lowest
codes limits at 0V as shown in Figure 1b.
Similarly, limiting can occur near full scale when VCC is
used as the reference. If VREF = VCC and the DAC full-scale
error (FSE) is positive, the output for the highest codes
limits at VCC as shown in Figure 1c. No full-scale limiting
can occur if the internal reference is used.
Offset and linearity are defined and tested over the region
of the DAC transfer function where no output limiting can
occur.
Internal Reference
In applications where a predictable output is required that
is independent of supply voltage, the LTC1663 has a userselectable internal reference. Selecting the internal reference will set the full-scale output voltage to 2.5V. This can
be useful in applications where the supply voltage is
poorly regulated.
Using the LT®1460 Micropower Series Reference as a
Power Supply for the LTC1663
In applications where the advantages of using the internal
reference are required but the full-scale range needs to be
greater than 2.5V, an external series reference can be
used. The LT1460 is ideal for use as a power supply for the
LTC1663 and can provide 3V, 3.3V and 5V full-scale
output voltage ranges. The LT1460 provides accuracy,
noise immunity and extended supply range to the LTC1663
when the LTC1663 is operated ratiometric to VCC. Since
both parts are available in SOT-23 packages, the PC board
space for this application is extremely small. See Figure 2.
9
LTC1663
U
W
U
U
APPLICATIONS INFORMATION
POSITIVE
FSE
VREF = VCC
OUTPUT
VOLTAGE
INPUT CODE
(c)
VREF = VCC
OUTPUT
VOLTAGE
0
512
INPUT CODE
1023
(a)
OUTPUT
VOLTAGE
0V
NEGATIVE
OFFSET
INPUT CODE
(b)
1663 F01
Figure 1. Effects of Rail-to-Rail Operation On a DAC Transfer Curve. (a) Overall Transfer Function (b) Effect of Negative
Offset for Codes Near Zero Scale (c) Effect of Positive Full-Scale Error for Input Codes Near Full Scale When VREF = VCC
1
3.9V TO 20V
0.1µF
IN
LT1460S3-3
2
OUT
+
GND
3V
0.01µF
3
4 (5)
VCC
5 (4)
TO
µP
1 (1)
SCL
LTC1663
OUT
3 (8)
0V ≤ VOUT ≤ 3V
SDA
GND
LTC1663 PIN NUMBERS IN PARENTHESES
REFER TO MSOP PACKAGE
2 (7)
Figure 2. LT1460 As Power Supply for the LTC1663
10
1663 F02
LTC1663
U
PACKAGE DESCRIPTION
Dimensions in inches (millimeters) unless otherwise noted.
MS8 Package
8-Lead Plastic MSOP
(LTC DWG # 05-08-1660)
0.040 ± 0.006
(1.02 ± 0.15)
0.007
(0.18)
0.034 ± 0.004
(0.86 ± 0.102)
0.118 ± 0.004*
(3.00 ± 0.102)
8
7 6
5
0° – 6° TYP
0.021 ± 0.006
(0.53 ± 0.015)
SEATING
PLANE 0.012
(0.30)
0.0256
REF
(0.65)
BSC
0.006 ± 0.004
(0.15 ± 0.102)
0.118 ± 0.004**
(3.00 ± 0.102)
0.193 ± 0.006
(4.90 ± 0.15)
MSOP (MS8) 1098
1
* DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH,
PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS.
INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
2 3
4
S5 Package
5-Lead Plastic SOT-23
(LTC DWG # 05-08-1633)
2.80 – 3.00
(0.110 – 0.118)
(NOTE 3)
2.60 – 3.00
(0.102 – 0.118)
1.50 – 1.75
(0.059 – 0.069)
0.35 – 0.55
(0.014 – 0.022)
1.90
(0.074)
REF
0.00 – 0.15
(0.00 – 0.006)
0.09 – 0.20
(0.004 – 0.008)
(NOTE 2)
0.95
(0.037)
REF
0.90 – 1.45
(0.035 – 0.057)
0.35 – 0.50
0.90 – 1.30
(0.014 – 0.020)
(0.035 – 0.051)
FIVE PLACES (NOTE 2)
S5 SOT-23 0599
NOTE:
1. DIMENSIONS ARE IN MILLIMETERS
2. DIMENSIONS ARE INCLUSIVE OF PLATING
3. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR
4. MOLD FLASH SHALL NOT EXCEED 0.254mm
5. PACKAGE EIAJ REFERENCE IS SC-74A (EIAJ)
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
11
LTC1663
U
TYPICAL APPLICATION
Program Up to 8 Control Outputs Per BUS and Place Them Where They Are Needed
VCC = 2.7V TO 5.5V
5
4
1
VCC
SMBus 1
LTC1694
+
0.1µF
SMBus 2
GND
2
+
5
4
VCC
SCL
1
SDA
LTC1663CMS8
8
6
VOUT
AD0
2
AD1
3
AD2
GND
SCL
µP
SDA
0.1µF
CONTROL
OUTPUT 0
0V ≤ VOUT0 < VCC
7
+
5
4
SCL
1
SDA
6
AD0
2
AD1
3
AD2
0.1µF
VCC
LTC1663CMS8
VOUT
8
CONTROL
OUTPUT 1
0V ≤ VOUT1 < VCC
GND
7
+
5
4
SCL
1
SDA
6
AD0
2
AD1
3
AD2
TO OTHER SMBus
DEVICES
0.1µF
VCC
LTC1663CMS8
VOUT
8
CONTROL
OUTPUT 7
0V ≤ VOUT7 < VCC
GND
7
1663 TA06
RELATED PARTS
PART NUMBER
DESCRIPTION
COMMENTS
LTC1694
SMBus I2C Accelerator
Dual SMBus Accelerator with Active AC and DC Pull-Up Current Sources
LTC1694-1
SMBus I2C Accelerator
Dual SMBus Accelerator with Active AC Pull-Up Current Only
LTC1659
Single Rail-to-Rail 12-Bit VOUT DAC in
8-Lead MSOP Package. VCC = 2.7V to 5.5V
Low Power Multiplying VOUT DAC. Output Swings from
GND to REF. REF Input Can Be Tied to VCC. 3-Wire Interface.
LTC1660/LTC1664
Octal/Quad 10-Bit VOUT DACs in 16-Pin Narrow SSOP VCC = 2.7V to 5.5V Micropower Rail-to-Rail Output. 3-Wire Interface.
Dual 10-Bit VOUT in 8-Lead MSOP Package
VCC = 2.7V to 5.5V Micropower Rail-to-Rail Output. 3-Wire Interface.
DACs
LTC1661
ADCs
LTC1285/LTC1288
8-Pin SO, 3V Micropower ADCs
1- or 2-Channel, Autoshutdown
LTC1286/LTC1298
8-Pin SO, 5V Micropower ADCs
1- or 2-Channel, Autoshutdown
LTC1594/LTC1598
4/8-Channel, 5V Micropower 12-Bit ADCs
Low Power, Small Size, Low Cost
12
Linear Technology Corporation
1663f LT/TP 0300 4K • PRINTED IN THE USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
 LINEAR TECHNOLOGY CORPORATION 1999