LT6658
Precision Dual Output, High Current,
Low Noise, Voltage Reference
FEATURES
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DESCRIPTION
The
LT
®
6658
is a family of precision dual output references
combining the performance of a precision voltage refer-
ence and a linear regulator that we call the Refulator™.
Both outputs are ideal for driving the reference inputs of
high resolution ADCs and DACs, even with heavy load-
ing, while simultaneously powering microcontrollers and
other circuitry. Both outputs have the same precision
specifications and track each other over temperature and
load. Each output can be configured with external resis-
tors to give an output voltage up to 6V.
Using Kelvin connections, the LT6658 typically has
0.1ppm/mA load regulation with up to 150mA load cur-
rent. A noise reduction pin is available to band-limit and
lower the total integrated noise.
Separate supply pins are provided for each output, provid-
ing an option to reduce power consumption and isolate
the buffer amplifiers. The outputs have excellent supply
rejection and are stable with 1µF to 50µF capacitors.
The LT6658 is available in a 16-lead MSOP with an
exposed pad for thermal management. Short circuit and
thermal protection help to prevent thermal overstress.
All registered trademarks and trademarks are the property of their respective owners.
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Dual Output Tracking Reference
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Each Output Configurable to 6V
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Output 1: 150mA Source/20mA Sink
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Output 2: 50mA Source/20mA Sink
Low Drift:
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A-Grade: 10ppm/°C Max
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B-Grade: 20ppm/°C Max
High Accuracy:
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A-Grade: ±0.05% Max
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B-Grade: ±0.1% Max
Low Noise: 1.5ppm
P-P
(0.1Hz to 10Hz)
Wide Operating Voltage Range to 36V
Load Regulation: 0.25µV/mA
AC PSRR: 96dB at 10kHz
Kelvin Sense Connection on Outputs
Thermal Shutdown
Separate Supply Pins for Each Output
Available Output Voltage Options: 1.2V, 1.8V, 2.5V, 3V,
3.3V, 5V. All Options are Adjustable
Available in Exposed Pad Package MSE16
APPLICATIONS
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Microcontroller or FPGA with ADC/DAC Applications
Data Acquisition Systems
Automotive Control and Monitoring
Precision Low Noise Regulators
Instrumentation and Process Control
TYPICAL APPLICATION
Precision Dual Output 2.5V Reference and Supply
V
IN1
V
IN2
V
IN
5V TO 36V
V
IN
OD
0.1µF
BYPASS
1µF
GND
LT6658-2.5
V
OUT1_F
V
OUT1_S
R
LOAD1
V
OUT1
2.5V
150mA
1µF
6658 TA01a
Output Voltage Temperature Drift Both Outputs
2.502
V
OUT2_S
R
LOAD2
1µF
OUTPUT VOLTAGE (V)
V
OUT2_F
V
OUT2
2.5V
50mA
2.501
2.500
2.499
I
LOAD1
= 150mA
V
OUT1
V
OUT2
0
25 50 75 100 125 150
TEMPERATURE (°C)
6658 TA01b
2.498
–50 –25
Document Feedback
For more information
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1
Rev B
LT6658
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
Supply Voltages
V
IN
, V
IN1
, V
IN2
to GND............................ –0.3V to 38V
Input Voltages
OD
to GND ............................................. –0.3V to 38V
V
OUT1_S
, V
OUT2_S
, NR, BYPASS to GND .. –0.3V to 6V
Output Voltages
V
OUT1_F
, V
OUT2_F
to GND ......................... –0.3V to 6V
Input Current
BYPASS ........................................................... ±10mA
Output Short-Circuit Duration .......................... Indefinite
Specified Temperature Range
I-Grade.................................................–40°C to 85°C
H-Grade ............................................. –40°C to 125°C
Operating Junction Temperature Range . –55°C to 150°C
Storage Temperature Range (Note 2)..... –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
(Note 3) ............................................................ 300°C
TOP VIEW
GND
GND
BYPASS
DNC
NR
GND
V
OUT2_S
V
OUT2_F
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
DNC
NC
V
IN
V
OUT1_S
V
OUT1_F
V
IN1
V
IN2
OD
17
GND
MSE PACKAGE
16-LEAD PLASTIC MSOP
T
JMAX
= 150°C,
θ
JC
= 10°C/W,
θJ
A
= 35°C/W
DNC: CONNECTED INTERNALLY
DO NOT CONNECT EXTERNAL CIRCUITRY TO THESE PINS
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
TUBE
LT6658AIMSE-1.2#PBF
LT6658BIMSE-1.2#PBF
LT6658AHMSE-1.2#PBF
LT6658BHMSE-1.2#PBF
LT6658AIMSE-1.8#PBF
LT6658BIMSE-1.8#PBF
LT6658AHMSE-1.8#PBF
LT6658BHMSE-1.8#PBF
LT6658AIMSE-2.5#PBF
LT6658BIMSE-2.5#PBF
LT6658AHMSE-2.5#PBF
LT6658BHMSE-2.5#PBF
LT6658AIMSE-3#PBF
LT6658BIMSE-3#PBF
LT6658AHMSE-3#PBF
LT6658BHMSE-3#PBF
LT6658AIMSE-3.3#PBF
LT6658BIMSE-3.3#PBF
TAPE AND REEL
LT6658AIMSE-1.2#TRPBF
LT6658BIMSE-1.2#TRPBF
LT6658AHMSE-1.2#TRPBF
LT6658BHMSE-1.2#TRPBF
LT6658AIMSE-1.8#TRPBF
LT6658BIMSE-1.8#TRPBF
LT6658AHMSE-1.8#TRPBF
LT6658BHMSE-1.8#TRPBF
LT6658AIMSE-2.5#TRPBF
LT6658BIMSE-2.5#TRPBF
LT6658AHMSE-2.5#TRPBF
LT6658BHMSE-2.5#TRPBF
LT6658AIMSE-3#TRPBF
LT6658BIMSE-3#TRPBF
LT6658AHMSE-3#TRPBF
LT6658BHMSE-3#TRPBF
LT6658AIMSE-3.3#TRPBF
LT6658BIMSE-3.3#TRPBF
PART MARKING* PACKAGE DESCRIPTION
665812
665812
665812
665812
665818
665818
665818
665818
665825
665825
665825
665825
66583
66583
66583
66583
665833
665833
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
SPECIFIED JUNCTION
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
Rev B
2
For more information
www.analog.com
LT6658
ORDER INFORMATION
TUBE
LT6658AHMSE-3.3#PBF
LT6658BHMSE-3.3#PBF
LT6658AIMSE-5#PBF
LT6658BIMSE-5#PBF
LT6658AHMSE-5#PBF
LT6658BHMSE-5#PBF
TAPE AND REEL
LT6658AHMSE-3.3#TRPBF
LT6658BHMSE-3.3#TRPBF
LT6658AIMSE-5#TRPBF
LT6658BIMSE-5#TRPBF
LT6658AHMSE-5#TRPBF
LT6658BHMSE-5#TRPBF
PART MARKING* PACKAGE DESCRIPTION
665833
665833
66585
66585
66585
66585
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
16-Lead Plastic MSOP
SPECIFIED JUNCTION
TEMPERATURE RANGE
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
*The temperature grade is identified by a label on the shipping container.
Consult ADI Marketing for parts specified with wider operating temperature ranges. Parts ending with PBF are RoHS and WEEE compliant.
Tape and reel specifications.
Some packages are available in 500 unit reels through designated sales channels with #TRMPBF suffix.
AVAILABLE OPTIONS
OUTPUT VOLTAGE
1.200V
INITIAL ACCURACY
0.05%
0.1%
0.05%
0.1%
1.800V
0.05%
0.1%
0.05%
0.1%
2.500V
0.05%
0.1%
0.05%
0.1%
3.000V
0.05%
0.1%
0.05%
0.1%
3.300V
0.05%
0.1%
0.05%
0.1%
5.000V
0.05%
0.1%
0.05%
0.1%
TEMPERATURE
COEFFICIENT
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
10ppm/°C
20ppm/°C
ORDER PART NUMBER **
LT6658AIMSE-1.2
LT6658BIMSE-1.2
LT6658AHMSE-1.2
LT6658BHMSE-1.2
LT6658AIMSE-1.8
LT6658BIMSE-1.8
LT6658AHMSE-1.8
LT6658BHMSE-1.8
LT6658AIMSE-2.5
LT6658BIMSE-2.5
LT6658AHMSE-2.5
LT6658BHMSE-2.5
LT6658AIMSE-3
LT6658BIMSE-3
LT6658AHMSE-3
LT6658BHMSE-3
LT6658AIMSE-3.3
LT6658BIMSE-3.3
LT6658AHMSE-3.3
LT6658BHMSE-3.3
LT6658AIMSE-5
LT6658BIMSE-5
LT6658AHMSE-5
LT6658BHMSE-5
SPECIFIED JUNCTION
TEMPERATURE RANGE
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
–40°C to 85°C
–40°C to 85°C
–40°C to 125°C
–40°C to 125°C
For more information
www.analog.com
3
Rev B
LT6658
ELECTRICAL CHARACTERISTICS
PARAMETER
Output Voltage Accuracy
CONDITIONS
LT6658A
LT6658B
LT6658AI
LT6658BI
LT6658AH
LT6658BH
LT6658A
LT6658B
LT6658-1.2, LT6658-1.8
4.5V ≤ V
IN
≤ 36V, V
IN
= V
IN1
= V
IN2
LT6658-2.5, LT6658-3.3, LT6658-5
V
OUT
+ 2.5V ≤ V
IN
≤ 36V, V
IN
= V
IN1
= V
IN2
Load Regulation (Note 5)
Output 1 Sourcing, ΔI
LOAD
= 0mA to 150mA
l
The
l
denotes the specifications which apply over the full specified temperature
range, otherwise specifications are at T
A
= 25°C. V
IN
= V
IN1
= V
IN2
= V
OUT1,2_F
+ 2.5V, C
OUT1,2
= 1.3µF, I
LOAD
= 0, unless otherwise noted.
MIN
–0.05
–0.1
–0.175
–0.35
–0.215
–0.43
3
10
2.0
l
TYP
MAX
0.05
0.1
0.175
0.35
0.215
0.43
10
20
5.0
6.0
4.5
5
1.25
2.0
3.25
3.75
3.2
3.75
3.2
3.75
4.0
4.5
4.5
5.0
4.8
5.3
7.0
7.5
2.3
2.5
2.3
2.5
2.2
2.5
2.2
2.5
3.2
3.6
3.0
1.1
1.8
1.5
1.8
2
2.5
UNITS
%
%
%
%
%
%
ppm/°C
ppm/°C
ppm/V
ppm/V
ppm/V
ppm/V
µV/mA
µV/mA
µV/mA
µV/mA
µV/mA
µV/mA
µV/mA
µV/mA
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
mA
mA
mA
mA
mA
mA
mA
mA
mA
Rev B
l
l
l
l
l
l
Output Voltage Temperature
Coefficient (Note 4)
Line Regulation (Note 5)
1.4
l
0.25
0.25
l
Output 2 Sourcing, ΔI
LOAD
= 0mA to 50mA (Note 6)
Output 1 Sinking, ΔI
LOAD
= 0mA to 20mA
l
0.25
0.25
l
Output 2 Sinking, ΔI
LOAD
= 0mA to 20mA
V
IN
Minimum Voltage
LT6658-1.2, LT6658-1.8, LT6658-2.5
ΔV
OUT
= 0.1%, I
OUT
= 0mA, V
IN1
= V
IN2
= 4.5V
LT6658-3
ΔV
OUT
= 0.1%, I
OUT
= 0mA, V
IN1
= V
IN2
= 5.5V
LT6658-3.3
ΔV
OUT
= 0.1%, I
OUT
= 0mA, V
IN1
= V
IN2
= 5.8V
LT6658-5
ΔV
OUT
= 0.1%, I
OUT
= 0mA, V
IN1
= V
IN2
= 7.5V
V
IN1
Dropout Voltage
LT6658-1.2, LT6658-1.8
ΔV
OUT1
= 0.1%, I
OUT1
= 0mA, V
IN
= V
IN2
= V
OUT
+ 4.5V
ΔV
OUT1
= 0.1%, I
OUT1
= 150mA, V
IN
= V
IN2
= V
OUT
+ 4.5V
LT6658-2.5, LT6658-3, LT6658-3.3, LT6658-5
ΔV
OUT1
= 0.1%, I
OUT1
= 0mA, V
IN
= V
IN2
= V
OUT
+ 2.5V
ΔV
OUT1
= 0.1%, I
OUT1
= 150mA, V
IN
= V
IN2
= V
OUT
+ 2.5V
V
IN2
Dropout Voltage
LT6658-1.2, LT6658-1.8
ΔV
OUT2
= 0.1%, I
OUT2
= 0mA, V
IN
= V
IN1
= V
OUT
+ 4.5V
ΔV
OUT2
= 0.1%, I
OUT2
= 50mA, V
IN
= V
IN1
= V
OUT
+ 4.5V
LT6658-2.5, LT6658-3, LT6658-3.3, LT6658-5
ΔV
OUT2
= 0.1%, I
OUT2
= 0mA, V
IN
= V
IN1
= V
OUT
+ 2.5V
ΔV
OUT2
= 0.1%, I
OUT2
= 50mA, V
IN
= V
IN1
= V
OUT
+ 2.5V
Supply Current
LT6658-1.2, V
OD
= 2.0V, No Load
LT6658-1.8, V
OD
= 2.0V, No Load
LT6658-2.5, LT6658-3, LT6658-3.3, LT6658-5, V
OD
= 2.0V, No Load
V
OD
= 0.8V, No Load
LT6658-1.2
LT6658-1.8
LT6658-2.5
LT6658-3
LT6658-3.3
LT6658-5
3.5
l
4.2
l
4.5
l
5.2
l
l
2.0
2.3
2.0
2.2
1.8
2.0
1.8
2.0
2.0
2.5
1.9
0.7
1.3
1.0
1.2
1.3
1.7
l
l
l
l
l
l
l
l
l
l
l
l
4
For more information
www.analog.com
LT6658
ELECTRICAL CHARACTERISTICS
PARAMETER
Output Short-Circuit Current
CONDITIONS
Short V
OUT1_F
to 400mV (Note 11)
Short V
OUT2_F
to 400mV (Note 11)
l
l
The
l
denotes the specifications which apply over the full operating temperature
range, otherwise specifications are at T
A
= 25°C. V
IN
= V
IN1
= V
IN2
= V
OUT1,2_F
+ 2.5V, C
OUT1,2
= 1.3µF, I
LOAD
= 0, unless otherwise noted.
MIN
170
65
TYP
270
120
0.8
1.0
1.5
1.6
1.7
2.2
0.5
2
8
0.9
135
l
l
l
l
MAX
UNITS
mA
mA
ppm
P–P
ppm
P–P
ppm
P–P
ppm
P–P
ppm
P–P
ppm
P–P
ppm
RMS
ppm
RMS
nV/√Hz
µV/°C
nA
V
V
μA
μA
dB
dB
μs
ppm/√kHr
ppm
ppm
Output Noise Voltage (Note 7) 0.1Hz ≤ f ≤ 10Hz
LT6658-1.2
LT6658-1.8
LT6658-2.5
LT6658-3
LT6658-3.3
LT6658-5
10Hz ≤ f ≤ 1kHz, C
OUT
= 1µF, C
NR
= 10µF, I
LOAD
= Full Current (Note 10)
10Hz ≤ f ≤ 1kHz, C
OUT
= 1µF, C
NR
= OPEN, I
LOAD
= Full Current (Note 10)
Frequency = 10kHz, C
OUT1
= 1µF, C
NR
= 10µF, I
LOAD
= Full Current (Note 10)
Output Voltage Tracking
V
OUT1_S
, V
OUT2_S
Pin Current
OD
Threshold Voltage
OD
Pin Current
Ripple Rejection
Tracking = Output 1 – Output 2
Unity Gain
Logic High Input Voltage
Logic Low Input Voltage
V
OD
= 0V
V
OD
= 36V
V
IN1
= V
OUT1
+ 3V, V
RIPPLE
= 0.5V
P–P
, f
RIPPLE
= 120Hz, I
LOAD
= 150mA,
C
OUT1
= 1µF, C
NR
= 10µF
V
IN2
= V
OUT2
+ 3V, V
RIPPLE
= 0.5V
P–P
, f
RIPPLE
= 120Hz, I
LOAD
= 50mA,
C
OUT2
= 1µF, C
NR
= 10µF
0.1% Settling, C
LOAD
= 1μF
ΔT = –40°C to 85°C
ΔT = –40°C to 125°C
2
0.8
30
0.3
107
107
160
120
30
45
45
1.5
Turn-On Time
Long Term Drift (Note 8)
Thermal Hysteresis (Note 9)
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2:
Thermal hysteresis can occur during storage at extreme
temperatures.
Note 3:
The stated temperature is typical for soldering of the leads during
manual rework. For detailed IR reflow recommendations, refer to the
Applications Information section.
Note 4:
Temperature coefficient is measured by dividing the maximum
change in output voltage by the specified temperature range.
Note 5:
Line and load regulation are measured on a pulse basis for
specified input voltage or load current ranges. Output changes due to die
temperature change must be taken into account separately.
Note 6:
V
OUT2
load regulation specification is limited by practical
automated test resolution. Please refer to the Typical Performance
Characteristics section for more information regarding actual typical
performance.
Note 7:
Peak-to-peak noise is measured with a 1-pole highpass filter at
0.1Hz and 2-pole lowpass filter at 10Hz. The unit is enclosed in a still-air
environment to eliminate thermocouple effects on the leads. The test
time is 10 seconds. RMS noise is measured on a spectrum analyzer in
a shielded environment where the intrinsic noise of the instrument is
removed to determine the actual noise of the device.
Note 8:
Long-term stability typically has a logarithmic characteristic
and therefore, changes after 1000 hours tend to be much smaller than
before that time. Total drift in the second thousand hours is normally less
than one third that of the first thousand hours with a continuing trend
toward reduced drift with time. Long-term stability will also be affected by
differential stresses between the IC and the board material created during
board assembly.
Note 9:
Hysteresis in output voltage is created by package stress that
differs depending on whether the IC was previously at a higher or
lower temperature. Output voltage is always measured at 25°C, but
the IC is cycled to the hot or cold temperature limit before successive
measurements. Hysteresis measures the maximum output change for the
averages of three hot or cold temperature cycles. For instruments that
are stored at well controlled temperatures (within 20 or 30 degrees of
operational temperature), it’s usually not a dominant error source. Typical
hysteresis is the worst-case of 25°C to cold to 25°C or 25°C to hot to
25°C, preconditioned by one thermal cycle.
Note 10:
The full current for I
LOAD
is 150mA and 50mA for Output 1 and
Output 2, respectively.
Note 11:
When the output voltage is less than 400mV, the output current
may foldback to less than the rated output current. Once the output is
released, the rated output current will be available.
For more information
www.analog.com
5
Rev B