LINER LTC1541 Micropower op amp, comparator and reference Datasheet

LTC1541/LTC1542
Micropower Op Amp,
Comparator and Reference
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FEATURES
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DESCRIPTION
Quiescent Current: 5µA Typ
Outputs Swing Rail-to-Rail
Low Op Amp Offset Voltage: 700µV Max
Reference Output Drives 0.01µF Capacitor
Internal 1.2V ±0.4% Reference Output (LTC1541)
Low Input Bias Current: 1nA Max
Reference Output Can Source Up to 2mA
Internal ±3mV Comparator Hysteresis
Comparator and Op Amp Input Range
Includes Ground
Op Amp Capable of Driving Up to 1000pF Load
Unity-Gain Stable and 12kHz Bandwidth
2.5V to 12.6V Supply
Voltage Range
Daisy-Chained
Control Outputs
Pin Compatible Upgrade for MAX951/MAX953
The LTC®1541/LTC1542 combine a micropower amplifier, comparator and bandgap reference (LTC1541) in an
8-pin package. The part operates from a single 2.5V to
12.6V or dual ±1.25V to ±6.3V supply with a typical supply
current of 5µA. Both the op amp and comparator feature
a common mode input voltage range that extends from the
negative supply to within 1.3V of the positive supply. The
op amp output stage swings from rail-to-rail. The
comparator’s inverting input is internally connected to the
reference output (LTC1541).
The reference output voltage is 1.2V ±1% over the
extended temperature range. The output can drive a
bypass capacitor of up to 0.01µF without any oscillations.
It can also source up to 2mA and sink up to 20µA.
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APPLICATIONS
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The op amp is internally compensated to be unity-gain
stable with typical GBW at 12kHz and slew rate of 8V/ms.
The comparator has ±3mV of internal hysteresis to ensure
clean output switching, even with slow moving input
signals.
Battery- or Solar-Powered Systems
Automotive Keyless Entry
Low Frequency, Local Area Alarms/Detectors
Infrared Receivers for Remote Controls
Smoke Detectors and Safety Sensors
GSM Portable Phones
The LTC1541/LTC1542 are available in MSOP and SO-8
packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATION
Pilot Light Flame Detector with Low-Battery Lockout
Op Amp VOS Distribution,
VCM = 2.5V, SO-8 Package
Total of 839 Units
VIN = 3.6V TO 9V
1k
–
+
10k
100k
1N457
10M
50
3
+
8
1
2.2µF 1/2 LTC1541
2
–
ICC = 7µA AT VIN = 5V
5
1M
+
1/2 LTC1541
6
7
LOW BATTERY
–
2M
10k
40
2N3904
SCR LOAD
2M
VN2222
VCC = 5V
VSS = 0V
OUTPUT HIGH = “ON”
OUTPUT LOW = “OFF”
PERCENT OF UNITS (%)
1N457
TYPE R
30
20
10
1.2V INTERNAL
REFERENCE
1541/42 • TA01
0
–600
0
300
–300
INPUT OFFSET VOLTAGE (µV)
600
1541/42 TA02
1
LTC1541/LTC1542
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ABSOLUTE MAXIMUM RATINGS
Supply Voltage ........................................................ 13V
Input Voltage .............................................– 0.3V to 13V
Output Voltage ...........................................– 0.3V to 13V
Output Short-Circuit Duration .......................... Indefinite
Storage Temperature Range ................. – 65°C to 150°C
Operating Temperature Range
Commercial ............................................. 0°C to 70°C
Industrial ............................................ – 40°C to 85°C
Lead Temperature (Soldering, 10 sec).................. 300°C
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PACKAGE/ORDER I FOR ATIO
ORDER PART
NUMBER
TOP VIEW
AMPOUT
AMPIN –
AMPIN+
VSS
1
2
3
4
8
7
6
5
VCC
COMPOUT
REF
COMPIN +
LTC1541CMS8
MS8 PACKAGE
8-LEAD PLASTIC MSOP
MS8 PART MARKING
TJMAX = 125°C, θJA = 250°C/W
LTBE
ORDER PART
NUMBER
TOP VIEW
AMPOUT 1
AMPIN–
8
VCC
2
7
COMPOUT
AMPIN+ 3
6
REF
VSS 4
5
COMPIN +
LTC1541CS8
LTC1541IS8
S8 PART MARKING
S8 PACKAGE
8-LEAD PLASTIC SO
1541
1541I
TJMAX = 125°C, θJA = 150°C/W
ORDER PART
NUMBER
TOP VIEW
AMPOUT
AMPIN –
AMPIN+
VSS
1
2
3
4
8
7
6
5
VCC
COMPOUT
COMPIN –
COMPIN +
LTC1542CMS8
MS8 PACKAGE
8-LEAD PLASTIC MSOP
MS8 PART MARKING
TJMAX = 125°C, θJA = 250°C/W
LTDE
ORDER PART
NUMBER
TOP VIEW
AMPOUT 1
AMPIN–
8
VCC
2
7
COMPOUT
AMPIN+ 3
6
COMPIN –
VSS 4
5
COMPIN +
LTC1542CS8
LTC1542IS8
S8 PART MARKING
S8 PACKAGE
8-LEAD PLASTIC SO
1542
1542I
TJMAX = 125°C, θJA = 150°C/W
Consult factory for Military grade parts.
ELECTRICAL CHARACTERISTICS
SYMBOL
PARAMETER
VCC = 5V, VSS = 0V, TA = 25°C, unless otherwise noted.
CONDITIONS
MIN
TYP
MAX
UNITS
Power Supply
VCC
Supply Voltage Range
ICC
Supply Current (Note 1)
●
2.5
5
12.6
V
µA
µA
µA
Commercial Grade
Industrial Grade
●
●
7.5
13
14
(SO-8)
Commercial Grade (SO-8)
Industrial Grade (SO-8)
●
●
1
1.5
2.0
mV
mV
mV
●
1.2
2.0
mV
mV
2.8
3.8
mV
mV
Comparator
VOS
Input Offset Voltage (Note 2)
(MSOP)
VTRIP
Trip Point (Note 3)
●
2
1.7
1
2.25
LTC1541/LTC1542
ELECTRICAL CHARACTERISTICS
VCC = 5V, VSS = 0V, TA = 25°C, unless otherwise noted.
SYMBOL
PARAMETER
IIN
Input Leakage Current (Note 4)
●
VCM
Input Common Mode Range
●
CMRR
Common Mode Rejection Ratio
PSRR
Power Supply Rejection Ratio
CONDITIONS
MIN
TYP
MAX
0.01
1
nA
VCC – 1.3V
V
VSS
UNITS
VCM = VSS to (VCC – 1.3V) (LTC1542)
Commercial Grade
Industrial Grade
●
●
0.25
0.30
0.35
mV/V
mV/V
mV/V
VCC = 3V to 12V
Commercial Grade (SO-8)
Industrial Grade (SO-8)
●
●
0.25
0.30
0.35
mV/V
mV/V
mV/V
tPD
Propagation Delay
Overdrive = 10mV
Overdrive = 100mV
VOH
Output High Voltage
IOUT = – 2mA
● VCC – 0.2V
VOL
Output Low Voltage
IOUT = 1.8mA
●
No Load (SO-8)
Commercial Grade (SO-8)
Industrial Grade (SO-8)
●
●
1.195
1.190
1.188
●
1.190
1.185
µs
µs
20
8
V
VSS + 0.3V
V
1.200
1.205
1.210
1.212
V
V
V
1.200
1.210
1.215
V
V
2
0.2
6
1.5
5
Reference (LTC1541 Only)
VREF
Reference Voltage
No Load (MSOP)
∆VREF
Load Regulation
ISOURCE = 2mA
ISINK = 10µA
●
●
en
Voltage Noise
0.1Hz to 10Hz
Input Offset Voltage
VCM = 2.5V (SO-8)
Commercial Grade (SO-8)
Industrial Grade (SO-8)
mV
mV
mV
µVP-P
16
Op Amp
VOS
●
●
0.7
1.25
1.65
mV
mV
mV
●
1.00
1.75
mV
mV
1
nA
VCM = 2.5V (MSOP)
IB
Input Bias Current
VCM = 2.5V
AVOL
Large-Signal Gain
AMPOUT = 0.5V to 4.5V, No Load
AMPOUT = 0.5V to 4.5V, RLOAD = 100k
Commercial Grade
Industrial Grade
0.01
●
●
●
80
60
38
35
1000
500
V/mV
V/mV
V/mV
V/mV
GBW
Gain Bandwidth
AV = 1V/V
12
kHz
SR
Slew Rate
AV = 1V/V
8
V/ms
VCM
Input Common Mode Range
CMRR
Common Mode Rejection Ratio
PSRR
VOH
VOL
Power Supply Rejection Ratio
Output High Voltage
Output Low Voltage
●
VSS
VCC – 1.3V
V
VCM = VSS to (VCC – 1.3V)
Commercial Grade
Industrial Grade
●
●
0.28
0.33
0.38
mV/V
mV/V
mV/V
VCC = 3V to 12V
Commercial Grade
Industrial Grade
●
●
0.19
0.21
0.23
mV/V
mV/V
mV/V
RLOAD = 100k to VSS
Commercial Grade
Industrial Grade
●
●
RLOAD = 100k to VSS
Commercial Grade
Industrial Grade
●
●
VCC – 0.07
VCC – 0.10
VCC – 0.12
V
V
V
VSS + 0.05
VSS + 0.10
VSS + 0.12
V
V
V
3
LTC1541/LTC1542
ELECTRICAL CHARACTERISTICS
SYMBOL
PARAMETER
ISOURCE
Output Source Current
ISINK
en
VCC = 5V, VSS = 0V, TA = 25°C, unless otherwise noted.
CONDITIONS
MIN
TYP
0.9
0.7
1.8
●
mA
mA
1.3
0.9
1.8
●
mA
mA
Output Sink Current
Input Noise Voltage
fO = 0.1Hz to 10Hz
MAX
UNITS
µVP-P
3
VCC = 3V, VSS = 0V, TA = 25°C, unless otherwise noted.
SYMBOL
PARAMETER
CONDITIONS
MIN
TYP
MAX
UNITS
12.6
V
Power Supply
VCC
Supply Voltage Range
ICC
Supply Current (Note 1)
●
2.5
Commercial Grade
Industrial Grade
●
●
7.0
12
13
µA
µA
µA
(SO-8)
Commercial Grade (SO-8)
Industrial Grade (SO-8)
●
●
1.0
1.5
2.0
mV
mV
mV
●
1.2
2.0
mV
mV
2.35
2.90
3.90
mV
mV
0.01
1
nA
4.5
Comparator
VOS
Input Offset Voltage (Note 2)
(MSOP)
VTRIP
Trip Point (Note 3)
●
IIN
Input Leakage Current (Note 4)
VCM
Input Common Mode Range
CMRR
Common Mode Rejection Ratio
PSRR
Power Supply Rejection Ratio
1.80
1.00
●
●
VCM = VSS to (VCC – 1.3V) (LTC1542)
Commercial Grade
Industrial Grade
VCC = 3V to 12V
Commercial Grade
Industrial Grade
VSS
VCC – 1.3
V
●
●
0.35
0.40
0.45
mV/V
mV/V
mV/V
●
●
0.25
0.30
0.35
mV/V
mV/V
mV/V
tPD
Propagation Delay
Overdrive = 10mV
Overdrive = 100mV
VOH
Output High Voltage
IOUT = – 2mA
●
VOL
Output Low Voltage
IOUT = 1.8mA
●
No Load (SO-8)
Commercial Grade (SO-8)
Industrial Grade (SO-8)
●
●
1.195
1.190
1.188
●
1.190
1.185
µs
µs
25
12
VCC – 0.2
V
VSS + 0.3
V
1.200
1.205
1.210
1.212
V
V
V
1.200
1.210
1.215
V
V
2
0.2
6
1.5
5
Reference (LTC1541 Only)
VREF
Reference Voltage
No Load (MSOP)
∆VREF
Load Regulation
ISOURCE = 1mA
ISINK = 10µA
en
Voltage Noise
0.1Hz to 10Hz
●
●
4
16
mV
mV
mV
µVP-P
LTC1541/LTC1542
ELECTRICAL CHARACTERISTICS
SYMBOL
VCC = 3V, VSS = 0V, TA = 25°C, unless otherwise noted.
PARAMETER
CONDITIONS
Input Offset Voltage
VCM = 1.5V (SO-8)
Commercial Grade (SO-8)
Industrial Grade (SO-8)
MIN
TYP
MAX
UNITS
●
●
0.70
1.25
1.65
mV
mV
mV
●
1.00
1.75
mV
mV
Op Amp
VOS
VCM = 1.5V (MSOP)
IB
Input Bias Current
VCM = 1.5V
AVOL
Large-Signal Gain
AMPOUT = 0.5V to 2.5V, No Load
AMPOUT = 0.5V to 2.5V, RLOAD = 100k
Commercial Grade
Industrial Grade
GBW
Gain Bandwidth
AV = 1V/V
SR
Slew Rate
AV = 1V/V
VCM
Input Common Mode Range
CMRR
Common Mode Rejection Ratio
PSRR
VOH
VOL
ISOURCE
ISINK
en
Power Supply Rejection Ratio
Output High Voltage
Output Low Voltage
●
●
80.0
45.5
22.0
20.0
1
1000
500
kHz
8
●
VSS
nA
V/mV
V/mV
V/mV
V/mV
12
V/ms
VCC – 1.3
V
VCM = VSS to (VCC – 1.3V)
Commercial Grade
Industrial Grade
●
●
0.40
0.50
1.00
mV/V
mV/V
mV/V
VCC = 3V to 12V
Commercial Grade
Industrial Grade
●
●
0.19
0.21
0.23
mV/V
mV/V
mV/V
RLOAD = 100k to VSS
Commercial Grade
Industrial Grade
●
●
RLOAD = 100k to VCC
Commercial Grade
Industrial Grade
●
●
Output Source Current
fO = 0.1Hz to 10Hz
The ● denotes specifications which apply over the full operating
temperature range.
Note 1: Supply current is tested with COMPIN+ = (REF – 100mV) for
LTC1541 and COMPIN+ = 0V, COMPIN – = 100mV for LTC1542.
Note 2: Input offset voltage is defined as the center of the input referred
hysteresis, VCM = REF (LTC1541). VCM = 1/2 VCC (LTC1542).
VCC – 0.07
VCC – 0.10
VCC – 0.12
V
V
V
VCC + 0.05
VCC + 0.10
VCC + 0.12
V
V
V
0.6
0.4
0.95
●
mA
mA
1.2
0.8
1.8
●
mA
mA
Output Sink Current
Input Noise Voltage
0.01
●
3
µVP-P
Note 3: Trip point is defined as the differential input voltage required to
make the comparator output change state. The difference between upper
and lower trip point is equal to the width of the input referred hysteresis,
VCM = REF (LTC1541). VCM = 1/2 VCC (LTC1542).
Note 4: The input leakage current is measured for COMPIN+ at 1.5V
(LTC1541) and COMPIN+ = COMPIN – = 1.5V (LTC1542).
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LTC1541/LTC1542
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TYPICAL PERFOR A CE CHARACTERISTICS
Supply Current vs Supply Voltage
10
VCC = 5V
VSS = GND
AMPIN – = AMPOUT
AMPIN + = 2.5V
SUPPLY CURRENT (µA)
9
7
6
5
4
3
2
8
7
6
5
4
1
3
0
2
–50
3
4
5 6 7 8 9 10 11 12
SUPPLY VOLTAGE (V)
1.203
1.201
1.200
1.199
1.198
1.196
0
25
50
75
TEMPERATURE (°C)
100
1
125
100
1000
10
LOAD CURRENT (µA)
Op Amp Output Voltage vs
Load Current
Op Amp DC Open-Loop Gain vs
Temperature
1x106
VCC = 5V
VSS = GND
1
VSUPPLY = ±1.5V
DC OPEN-LOOP GAIN (V/V)
0.8
1.200
1.199
1.198
1.197
1x10
5
0.6
1x104
1x103
VCC = 5V
VSS = GND
RLOAD = 100kΩ
1x102
1.196
100
–50
125
0.4
VSUPPLY
= ± 2.5V
SINKING
CURRENT
0.2
0
SOURCING
CURRENT
–0.2
VSUPPLY
= ± 2.5V
–0.4
–0.6
–0.8
VSUPPLY = ±1.5V
–1
1x101
0
25
50
75
TEMPERATURE (°C)
–25
0
25
50
75
TEMPERATURE (°C)
100
1
125
100
1000
10
LOAD CURRENT (µA)
1541/42 TPC05
Op Amp Short-Circuit Current vs
Supply Voltage
Op Amp DC Open-Loop Gain vs
Supply Voltage
5
RLOAD = 100kΩ
4
2
0
–2
SHORT TO VCC
–4
NONINVERTING
VSS = GND
AMPIN+ = VCC /2
–6
–8
1000
100
10
1
0.1
–10
2
3
4
5 6 7 8 9 10 11 12
SUPPLY VOLTAGE (V)
4
OUTPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
SHORT TO VSS
DC OPEN-LOOP GAIN (V/mV)
8
VCC = 5V
VSS = GND
SOURCING
CURRENT
3
2
SINKING
CURRENT
1
2
3
4
5 6 7 8 9 10 11 12
SUPPLY VOLTAGE (V)
1541/42 TPC08
1541/42 TPC07
6
Comparator Output Voltage vs
Load Current
10,000
6
10000
1541/42 TPC06
1541/42 TPC04
10
10000
1541/42 TPC03
1.202
–25
SINKING
CURRENT
1.197
1541/42 TPC02
Reference Output Voltage vs
Temperature
1.195
–50
SOURCING
CURRENT
1.202
1.195
–25
1541/42 TPC01
1.201
VCC = 5V
VSS = GND
1.204
OUTPUT VOLTAGE (mV)
2
REFERENCE OUTPUT VOLTAGE (V)
NONINVERTING
VSS = GND
AMPIN+ = VCC /2
8
SUPPLY CURRENT (µA)
1.205
10
9
REFERENCE OUTPUT (V)
Reference Output Voltage vs
Load Current
Supply Current vs Temperature
0
0.01
0.1
1
10
100
LOAD CURRENT (mA)
1000
1541/42 TPC09
LTC1541/LTC1542
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TYPICAL PERFOR A CE CHARACTERISTICS
Comparator Short-Circuit Current
vs Supply Voltage
Op Amp Small-Signal Transient
Response
250
SHORT-CIRCUIT CURRENT (mA)
200
150
SHORT TO VSS
INPUT
200mV/DIV
100
50
OUTPUT
100mV/DIV
0
–50
–100
SHORT TO VCC
–150
NONINVERTING
AVCL = 1V/V
LOAD = 100kΩ//100pF TO VSS
VSUPPLY = 5V
–200
–250
2
3
4
5 6 7 8 9 10 11 12
SUPPLY VOLTAGE (V)
1541/42 TPC11
1541/42 TPC10
Op Amp Large-Signal Transient
Response
Op Amp Open-Loop Gain and
Phase vs Frequency
OUTPUT
1V/DIV
NONINVERTING
AVCL = 1V/V
LOAD = 100kΩ//100pF TO VSS
VSUPPLY = 5V
1541/42 TPC11
0
100
–45
–90
80
PHASE
–135
60
–180
40
GAIN
–225
20
0
–20
–40
–270
VCC = 5V
VSS = GND
RLOAD = 100kΩ
10
100
1k
10k
FREQUENCY (Hz)
PHASE SHIFT (DEGREES)
OPEN-LOOP GAIN (dB)
INPUT
2V/DIV
120
–315
100k
–360
1M
1541/42 TPC13
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LTC1541/LTC1542
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PIN FUNCTIONS
AMPOUT (Pin 1): Op Amp Output. The output can swing
from rail-to-rail while driving a capacitive load of up to
1000pF. The output can source and sink 0.7mA (min).
AMPIN– (Pin 2): Inverting Input of Op Amp. The input
common mode ranges from VSS to (VCC – 1.3V). The input
current is typically 10pA at 25°C.
REF (Pin 6) (LTC1541): Reference Output. VREF = 1.2V
±1% over industrial temperature range, and is also connected to inverting comparator input internally. This device can source up to 2mA and sink up to 20µA. The output
can drive a bypass capacitor of up to 0.01µF without
oscillation.
AMPIN+ (Pin 3): Noninverting Input of Op Amp. The input
common mode ranges from VSS to (VCC – 1.3V). The input
current is typically 10pA at 25°C.
COMPIN – (Pin 6) (LTC1542): Inverting Input of Comparator. The input common mode ranges from V SS to
(VCC – 1.3V). The input current is typically 10pA at 25°C.
VSS (Pin 4): Negative Supply or Ground Connection.
COMPOUT (Pin 7): Comparator Output. The output can
source 20mA and sink 5mA.
COMPIN+ (Pin 5): Noninverting Input of Comparator. The
input common mode ranges from VSS to (VCC – 1.3V). The
input current is typically 10pA at 25°C.
VCC (Pin 8): Positive Supply, 2.5V ≤ VCC ≤ 12.6V. The supply
bypass capacitors are not required if the supply impedance
is low. For single supply applications, it is a good general
practice to bypass VCC with a 0.1µF capacitor to ground.
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BLOCK DIAGRA S
LTC1541
+
1 AMPOUT
OP AMP
VCC
8
COMPOUT
7
REF
6
COMPIN +
5
–
2 AMPIN –
×1
3 AMPIN +
COMP
–
4 VSS
+
LTC1541 • BD
LTC1542
+
1 AMPOUT
OP AMP
VCC
8
COMPOUT
7
COMPIN –
6
COMPIN+
5
–
2 AMPIN –
COMP
3 AMPIN +
–
4 VSS
+
LTC1542 • BD
8
LTC1541/LTC1542
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APPLICATIONS INFORMATION
The LTC1541/LTC1542 are a combination of a micropower
op amp, comparator and 1.2V ±1% reference (LTC1541)
in an 8-pin package. The LTC1541 has the negative input
of the comparator internally connected to the reference
output. The supply voltage range is from 2.5V to 12.6V for
single supply and ±1.25V to ±6.3V for dual supplies. The
supply current is a mere 5µA (typical) with a 5V single
supply.
Op Amp
The op amp is internally compensated to be unity-gain
stable, with typical GBW at 12kHz and slew rate of 8V/ms.
The output can drive a capacitive load of up to 1000pF and
swings from rail-to-rail. The input range is from the
negative rail to within 1.3V of the positive rail. The input
bias current is less than 1nA maximum at the extended
temperature range.
8
LTC1541 VCC
6
REF
×1
R1
C1
GND
4
1541/42 • F01
Figure 1. Damping the Reference Output
Comparator
The comparator has a high impedance differential input
stage with a common mode input range from the negative
rail to within 1.3V of the positive rail. The CMOS output
stage can swing from rail-to-rail and source up to 20mA
continuously. The output stage has been designed to
eliminate the power supply glitches that normally occur
when the output changes logic state. In addition, internal
hysteresis (±3mV) ensures clean output switching even
with slow moving input signals. The negative input is
internally connected to the reference for the LTC1541.
Reference
The output can source up to 2mA and sink up to 20µA with
a 5V supply. The output can drive a bypass capacitor of up
to 0.01µF without oscillation and by inserting a series
resistor, capacitance values up to 100µF can be used
(Figure 1). Figure 2 shows the resistor value required for
different capacitor values to achieve critical damping.
Bypassing the reference can help prevent false tripping of
the comparator by preventing glitches on VCC or reference
load transients from disturbing the reference output voltage. Figures 3a and 3b show the bypass reference output
with a square wave applied to the VCC pin while resistor R1
damps the reference response. Note that the comparator
output doesn’t trip.
Op Amp Stability
Unlike other industry standard micropower CMOS op
amps, the op amp in the LTC1541/LTC1542 maintain
stability in unity-gain configuration while driving heavy
capacitive loads of up to 1000pF.
Although this family is primarily designed for low frequency
applications, good layout is extremely important. Low power,
high impedance circuits may increase the effects of board
leakage and stray capacitance. For example, the combination of a 10M resistance (from leakage between traces on a
contaminated, poorly designed PC board) and a 1pF stray
capacitance provides a pole at approximately 16kHz, which
is near the amplifier’s bandwidth. Board routing and layout
should minimize leakage and stray capacitance. In some
cases, stray capacitance may be unavoidable and it may be
necessary to add a small capacitor across the feedback
resistor to compensate (Figure 4); select the smallest
capacitor value that ensures stability.
Inputs
The input common mode range for both the op amp and
comparator is from the negative supply to within 1.3V of the
positive supply. The inputs can be taken more than 300mV
below the negative supply without damaging the device if
the current out of the pin is limited to less than 1mA. Unlike
bipolar input op amps and comparators, the outputs of the
CMOS LTC1541/LTC1542 will not reverse phase when the
inputs are taken above the common mode input range.
The internal bandgap reference has an output voltage of
1.2V ±1% over the industrial grade temperature range.
9
LTC1541/LTC1542
U
U
W
U
APPLICATIONS INFORMATION
1000
LTC1541
RESISTOR VALUE (kΩ)
8 VCC
100
7 COMPOUT
5V TO 8V
6 REF
×1
10
R1
430Ω
–
1
0.1
0.001
0.01
0.1
1
CAPACITOR VALUE (µF)
C1
1µF
10
5
COMP
COMPIN +
+
GND
4
1541/42 • F02
Figure 2. Damping Resistance vs Bypass Capacitor Value
1541/42 • F03a
Figure 3a. Reference Transient Response Test Circuit
8V
V+
AMPIN +
2mV/DIV
5V
+
OP AMP
VREF
AMPOUT
–
R2
OUT
R1
2ms/DIV
2pF TO 10pF
LTC1541 • F03b
1541/42 • F04
Figure 4. Compensation for Feedback Node Capacitance
Figure 3b. Reference and Comparator Output Transient Response
U
TYPICAL APPLICATIO S
Shunt Battery Charger with Low-Battery Load Disconnect
Si9405
2A
FUSE
6.8V
ZENER
1N754
3.65M
1A
SOLAR
ARRAY
3
+
1/2
LTC1541
2
340k
–
TIP121
8
7.5Ω
10W
DALE
HLM-10
1M
8M
1M
5
1
12V
5AHR
GEL CELL
6
4
+
1/2
LTC1541
7
LOAD
VN2222
–
1M
VREF = 1.2V
(INTERNAL)
1541/42 TA06
10
LTC1541/LTC1542
U
TYPICAL APPLICATIO S
Negative Reference
Sungle Supply Function Generator
VCC
3V TO 9V
VCC
3V TO 12V
0.1µF
200k
5M
2
2
3
–
8
LTC1542
OP AMP
+
LT1634-2.5
1
–
3
+
4
VSS
–3V
1
LTC1542
OP AMP
5M
VOUT
–2.5V
8
4
R2
500k
6
5
R1
10M
–
7
LTC1542
COMP
+
R3
5M
1541/42 TA04
1541/42 TA05
FREQ ≈
U
PACKAGE DESCRIPTION
R1
4C • R2 • R3
Dimensions in inches (millimeters) unless otherwise noted.
MS8 Package
8-Lead Plastic MSOP
(LTC DWG # 05-08-1660)
0.118 ± 0.004*
(3.00 ± 0.10)
0.040 ± 0.006
(1.02 ± 0.15)
0.007
(0.18)
0.006 ± 0.004
(0.15 ± 0.10)
8
7 6
5
0° – 6° TYP
SEATING
PLANE
0.021 ± 0.004
(0.53 ± 0.01)
0.118 ± 0.004**
(3.00 ± 0.10)
0.192 ± 0.004
(4.88 ± 0.10)
0.012
(0.30)
0.025
(0.65)
TYP
MSOP08 0596
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
S8 Package
8-Lead Plastic Small Outline (Narrow 0.150)
(LTC DWG # 05-08-1610)
0.189 – 0.197*
(4.801 – 5.004)
0.010 – 0.020
× 45°
(0.254 – 0.508)
0.008 – 0.010
(0.203 – 0.254)
0.053 – 0.069
(1.346 – 1.752)
0°– 8° TYP
0.016 – 0.050
0.406 – 1.270
0.014 – 0.019
(0.355 – 0.483)
*DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH
SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE
**DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD
FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE
8
7
6
5
0.004 – 0.010
(0.101 – 0.254)
0.050
(1.270)
BSC
0.150 – 0.157**
(3.810 – 3.988)
0.228 – 0.244
(5.791 – 6.197)
SO8 0695
1
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.
2
3
4
11
LTC1541/LTC1542
U
TYPICAL APPLICATIO S
Voltage Control Oscillator
C1
0.047µF
VCC
R1
300k
2
1M
VIN
0V – VCC
3
R2
150k
–
8
LTC1542
OP AMP
+
R4
5M
1
6
4
5
1M
VC
2.4C • R1 • VCC
VALUES SHOWN ARE FOR
100Hz WITH VIN = VCC
–
LTC1542
COMP
7
5V
0V
VOUT
+
FREQ ≈
R4
1.1M
VN2222
R3
500k
VN2222
1541/42 TA03
Linear Lithium-Ion Charger
D1
1N5817
Q1
FZT2907A
VIN
6V
300mA
C3
0.01µF
R1
220Ω
0.25W
R8
249k
0.5%
IC1
VCC 8
LTC1541
Q2
2N3906
×1
2
R1
1M
SHUTDOWN
7
1
3
–
–
+
+
300mA
4.2V FLOAT
6
Li-ION
5
C2
0.1µF
4 VSS
R3
3.83k
1%
R5
2.2M
R4
100k
1%
C1
4700pF
R7
0.15Ω
R6
33k
R9
100k
0.5%
1541/42 TA07
RELATED PARTS
PART NUMBER
LT® 1078/LT1079
LT1178/LT1179
LT1490/LT1491
LT1635
LT2078/LT2079
LT2178/LT2179
12
DESCRIPTION
Dual/Quad Micropower, Single Supply Precision Op Amps
COMMENTS
70µV, VOS Max and 0.4µV/°C Drift, 200kHz GBW, 0.07V/µs
Slew Rate, Input/Output Common Mode Includes Ground
Dual/Quad 17µA Max, Single Supply Precision Op Amps
70µV, VOS Max and 2.5µV/°C Drift Max, 85kHz GBW, 0.04V/µs
Slew Rate, Input/Output Common Mode Includes Ground
Dual/Quad Micropower Rail-to-Rail Input and Output Op Amps Single Supply Input Range: – 0.4V to 44V, Micropower 50µA
Amplifier, Rail-to-Rail Input and Output, 200kHz GBW
Micropower Rail-to-Rail Op Amp and Reference
130µA of Supply Current, 1.3mV VOS Max
Dual/Quad Micropower, Single Supply Precision Op Amps
SO-8 and 14-Lead Standard Pinout, 70µV VOS Max, 200kHz GBW
Dual/Quad 17µA Max, Single Supply Precision Op Amps
SO-8 and 14-Lead Standard Pinout, 70µV VOS Max, 85kHz GBW
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408)432-1900 ● FAX: (408) 434-0507 ● www.linear-tech.com
15412f LT/TP 0798 4K • PRINTED IN USA
 LINEAR TECHNOLOGY CORPORATION 1998