Maxim MAX874ESA 10î¼a, low-dropout, precision voltage reference Datasheet

19-0005; Rev 2; 6/97
10µA, Low-Dropout,
Precision Voltage References
Features
The MAX872/MAX874 precision 2.5V and 4.096V micropower voltage references consume a maximum of only
10µA and operate from supply voltages up to 20V. The
combination of ultra-low quiescent current and low
200mV dropout makes them ideal for battery-powered
equipment. They source and sink up to 500µA with only
200mV input voltage headroom, which makes the 2.5V
MAX872 ideal for use with a 3V supply and the 4.096V
MAX874 ideal for use with a 5V supply.
♦ Output Voltage
2.500V ±0.2% (MAX872)
4.096V ±0.2% (MAX874)
Initial accuracy of 0.2% at +25°C (±5mV for the MAX872,
±8mV for the MAX874) and low 40ppm/°C max drift make
these references suitable for a wide range of precision
applications.
♦ Line Regulation Over Temp.
20µV/V (MAX872)
75µV/V (MAX874)
♦ Wide Operating Voltage Range
2.7V to 20V (MAX872)
4.3V to 20V (MAX874)
♦ 10µA Max Supply Current
♦ 40ppm/°C Max Drift Over Extended Temp. Range
♦ Load Regulation Over Temp.
0.6mV/mA Max (MAX872)
1.0mV/mA Max (MAX874)
Applications
♦ ±500µA Sink/Source Current
Ordering Information
Hand-Held Instruments
Battery-Operated Equipment
Power Supplies
Typical Operating Circuit
3.0V (MAX872)
5.0V (MAX874)
PART
TEMP. RANGE
PIN-PACKAGE
MAX872CPA
0°C to +70°C
8 Plastic DIP
MAX872CSA
MAX872C/D
MAX872EPA
MAX872ESA
MAX874CPA
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
0°C to +70°C
8 SO
Dice*
8 Plastic DIP
8 SO
8 Plastic DIP
MAX874CSA
MAX874C/D
MAX874EPA
MAX874ESA
0°C to +70°C
0°C to +70°C
-40°C to +85°C
-40°C to +85°C
8 SO
Dice*
8 Plastic DIP
8 SO
* Dice are specified at +25°C only.
VIN
Pin Configuration
VOUT
TOP VIEW
MAX872
MAX874
TRIM
I.C. 1
VIN 2
GND
TEMP
3
MAX872
MAX874
GND 4
REFERENCE WITH TRIMMED OUTPUT
8
COMP
7
I.C.
6
VOUT
5
TRIM
DIP/SO
________________________________________________________________ Maxim Integrated Products
1
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MAX872/MAX874
General Description
MAX872/MAX874
10µA, Low-Dropout,
Precision Voltage References
ABSOLUTE MAXIMUM RATINGS
Supply Voltage .......................................................................24V
Output Short-Circuit Duration ..........Continuous to Either Supply
CCOMP Input...........................................................-0.3V to VOUT
TRIM Input ...................................................-0.3V to (VIN + 0.3V)
TEMP Output ...............................................-0.3V to (VIN + 0.3V)
Continuous Power Dissipation (TA = +70°C)
Plastic DIP (derate 9.09mW/°C above +70°C) .............727mW
SO (derate 5.88mW/°C above +70°C) ..........................471mW
Operating Temperature Ranges
MAX87_C__ .........................................................0°C to +70°C
MAX87_E__ ......................................................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Junction Temperature Range (Tj) ......................-65°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS—MAX872
(VIN = 2.7V, IL = 0mA, TA = +25°C, unless otherwise noted.)
PARAMETER
Output Voltage
Output Voltage Noise
SYMBOL
VOUT
en
Line Regulation
VOUT/VIN
Load Regulation (Note 1)
VOUT/IOUT
Quiescent Supply Current
Change in Supply Current vs. VIN
Short-Circuit Output Current
TEMP Voltage
VOUT Adjustment Range
CONDITIONS
MIN
TYP
MAX
2.495
2.500
2.505
0.1Hz to 10Hz
60
VIN = 4.5V to 20V
4
12
VIN = 2.7V to 5.5V
80
250
Sourcing 0mA to 0.5mA
0.2
0.5
Sinking 0mA to -0.5mA
4
12
IQ
IQ/VIN
ISC
V
µVp-p
µV/V
mV/mA
6.5
10
µA
0.35
0.55
µA/V
VOUT short to GND
6
15
VOUT short to VIN
3
9
VIN = 2.7V to 20V
VTEMP
VADJ
UNITS
690
VOUT ≥ VOUT + 0.2V
mA
mV
+75/-20 +100/-25
mV
ELECTRICAL CHARACTERISTICS—MAX874
(VIN = 4.3V, IL = 0mA, TA = +25°C, unless otherwise noted.)
PARAMETER
Output Voltage
Output Voltage Noise
SYMBOL
VOUT
en
Line Regulation
VOUT/VIN
Load Regulation (Note 1)
VOUT/IOUT
Quiescent Supply Current
Change in Supply Current vs. VIN
Short-Circuit Output Current
TEMP Voltage
VOUT Adjustment Range
2
CONDITIONS
MIN
TYP
MAX
4.088
4.096
4.104
0.1Hz to 10Hz
90
VIN = 4.3V to 20V
15
75
Sourcing 0mA to 0.5mA
0.15
0.9
Sinking 0mA to -0.5mA
6
15
IQ
IQ/VIN
ISC
V
µVp-p
µV/V
mV/mA
6.5
10
µA
0.35
0.55
µA/V
VOUT short to GND
6
15
VOUT short to VIN
5
25
VIN = 4.3V to 20V
VTEMP
VADJ
UNITS
VOUT ≥ VOUT + 0.2V
±150
mA
690
mV
±200
mV
_______________________________________________________________________________________
10µA, Low-Dropout,
Precision Voltage References
(VIN = 2.7V, IL = 0mA, TA = 0°C to +70°C, unless otherwise noted.)
PARAMETER
Output Voltage
SYMBOL
CONDITIONS
VOUT
Output Voltage Temperature
Coefficient
TCVOUT
Line Regulation
VOUT/VIN
Load Regulation (Note 1)
VOUT/IOUT
Quiescent Supply Current
TYP
2.4905
20
MAX
UNITS
2.5095
V
40
ppm/°C
VIN = 4.5V to 20V
20
VIN = 2.7V to 5.5V
300
Sourcing 0mA to 0.4mA
0.6
Sinking 0mA to -0.4mA
15
15
µA
0.7
µA/V
IQ
Change in Supply Current vs. VIN
IQ/VIN
VIN = 2.7V to 20V
VOUT Adjustment Range
VADJ
VIN ≥ VOUT + 0.2V
TEMP Output Temperature
Coefficient
MIN
+75/-20
TCVTEMP
µV/V
mV/mA
mV
2.3
mV/°C
ELECTRICAL CHARACTERISTICS—MAX874C
(VIN = 4.3V, IL = 0mA, TA = 0°C to +70°C, unless otherwise noted.)
PARAMETER
Output Voltage
SYMBOL
CONDITIONS
MAX
UNITS
4.1115
V
40
ppm/°C
VIN = 4.3V to 20V
75
µV/V
Sourcing 0mA to 0.4mA
1.0
Sinking 0mA to -0.4mA
25
VOUT
Output Voltage Temperature
Coefficient
TCVOUT
Line Regulation
VOUT/VIN
Load Regulation (Note 1)
VOUT/IOUT
Quiescent Supply Current
IQ
20
IQ/VIN
VIN = 4.3V to 20V
VOUT Adjustment Range
VADJ
VIN ≥ VOUT + 0.2V
TCVTEMP
TYP
4.0805
Change in Supply Current vs. VIN
TEMP Output Temperature
Coefficient
MIN
±150
mV/mA
15
µA
0.7
µA/V
mV
2.3
mV/°C
Note 1: If the load current exceeds 300µA, connect a minimum of 1000pF from VOUT to GND. Note that if a capacitor larger than
1000pF is used, a compensation capacitor of COUT/100 must be connected from VOUT to COMP.
_______________________________________________________________________________________
3
MAX872/MAX874
ELECTRICAL CHARACTERISTICS—MAX872C
MAX872/MAX874
10µA, Low-Dropout,
Precision Voltage References
ELECTRICAL CHARACTERISTICS—MAX872E
(VIN = 2.7V, IL = 0mA, TA = -40°C to +85°C, unless otherwise noted.)
PARAMETER
Output Voltage
SYMBOL
Output Voltage Temperature
Coefficient
TCVOUT
Line Regulation
VOUT/VIN
Load Regulation
VOUT/IOUT
Quiescent Supply Current
CONDITIONS
VOUT
TYP
20
MAX
UNITS
2.512
V
40
ppm/°C
VIN = 4.5V to 20V
20
VIN = 2.7V to 5.5V
300
Sourcing 0mA to 0.30mA
0.6
Sinking 0mA to -0.30mA
15
15
µA
0.7
µA/V
IQ
Change in Supply Current vs. VIN
IQ/VIN
VIN = 2.7V to 20V
VOUT Adjustment Range
VADJ
VIN ≥ VOUT + 0.2V
TEMP Output Temperature
Coefficient
MIN
2.488
+75/-20
TCVTEMP
µV/V
mV/mA
mV
2.3
mV/°C
ELECTRICAL CHARACTERISTICS—MAX874E
(VIN = 4.3V, IL = 0mA, TA = -40°C to +85°C, unless otherwise noted.)
PARAMETER
Output Voltage
SYMBOL
Output Voltage Temperature
Coefficient
TCVOUT
Line Regulation
VOUT/VIN
Load Regulation
Quiescent Supply Current
CONDITIONS
MAX
UNITS
4.115
V
40
ppm/°C
VIN = 4.3V to 20V
75
µV/V
Sourcing 0mA to 0.30mA
1.0
Sinking 0mA to -0.30mA
25
15
µA
0.7
µA/V
VOUT
VOUT/IOUT
IQ
IQ/VIN
VIN = 4.3V to 20V
VOUT Adjustment Range
VADJ
VIN ≥ VOUT + 0.2V
4
TYP
20
Change in Supply Current vs. VIN
TEMP Output Temperature
Coefficient
MIN
4.077
TCVTEMP
±150
mV/mA
mV
2.3
_______________________________________________________________________________________
mV/°C
10µA, Low-Dropout,
Precision Voltage References
SUPPLY CURRENT
vs. INPUT VOLTAGE
TA = +85°C
150
TA = +25°C
100
15
MAX874
10
MAX872
5
50
NO LOAD
SUPPLY CURRENT (µA)
200
20
MAX872/74-02
MAX872/74-01
20
SUPPLY CURRENT (µA)
DROPOUT VOLTAGE (mV)
250
MAX872
SUPPLY CURRENT vs. TEMPERATURE
MAX872/74-03
DROPOUT VOLTAGE
vs. SOURCE CURRENT
VIN = 20V
15
VIN = 10V
VIN = 5V
10
TA = -40°C
VIN = 3V
0
0
100
150
200
250
4
6
8
-50
10 12 14 16 18 20
-25
0
25
50
75
100
INPUT VOLTAGE (V)
TEMPERATURE (°C)
MAX874
SUPPLY CURRENT vs. TEMPERATURE
MAX872
OUTPUT VOLTAGE vs. INPUT VOLTAGE
MAX874
OUTPUT VOLTAGE vs. INPUT VOLTAGE
VIN = 20V
15
VIN = 10V
2.500
MAX872/74-06
4.098
2.503
VOUT (V)
20
4.100
MAX872/74-05
MAX872/74-04
2.505
VOUT (V)
4.096
4.094
VIN = 5V
2.498
10
4.092
2.495
5
-50
-25
0
25
50
75
4.090
2
100
4
6
8
10
12
14
16
18
20
4
6
8
10
12
14
16
TEMPERATURE (°C)
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
MAX872
LOAD REGULATION vs. TEMPERATURE
MAX874
LOAD REGULATION vs. TEMPERATURE
MAX872
OUTPUT VOLTAGE
vs. SOURCE CURRENT
2
SINKING 0µA TO -500µA
1
2.501
3
SINKING 0µA TO -500µA
2.499
SOURCING 0µA TO 500µA
SOURCING 0µA TO 500µA
0
0
-25
0
25
50
TEMPERATURE (°C)
2.500
2
1
-50
20
MAX872/74-09
4
18
2.502
VOUT (V)
3
5
MAX872/74-08
MAX872/74-07
4
LOAD REGULATION (mV/mA)
SUPPLY CURRENT (µA)
2
SOURCE CURRENT (µA)
25
LOAD REGULATION (mV/mA)
5
0
75
100
2.498
-50
-25
0
25
50
TEMPERATURE (°C)
75
100
0.01
0.1
1
10
SOURCE CURRENT (mA)
_______________________________________________________________________________________
5
MAX872/MAX874
Typical Operating Characteristics
(VIN = 3V (MAX872), VIN = 5V (MAX874), no load, TA = +25°C, unless otherwise noted.)
Typical Operating Characteristics (continued)
(VIN = 3V (MAX872), VIN = 5V (MAX874), no load, TA = +25°C, unless otherwise noted.)
2.502
4.098
VOUT (V)
VOUT (V)
VOUT (V)
4.096
4.094
2.498
4.092
4.090
2.496
0.1
1
10
-25
0
25
50
75
TEMPERATURE (°C)
POWER-SUPPLY REJECTION RATIO
vs. FREQUENCY
TEMP OUTPUT
vs. TEMPERATURE
0
25
1.5
0.8
0.7
MAX872
1.0
1k
FREQUENCY (Hz)
MAX872
1Hz TO 100Hz NOISE
6
NOISE IS FROM
0.01Hz TO FREQUENCY
INDICATED
0
0.5
100
100
0.5
-80
10
75
MAX874
0.6
1
50
2.0
NOISE (mVp-p)
INPUT FILTER
CIRCUIT IN FIGURE 2
-60
NO LOAD
0.9
TEMP OUTPUT (V)
NO INPUT FILTER
-25
NOISE vs. FREQUENCY
1.0
MAX872/74-13
NO LOAD
VIN = +3V TO +5V (MAX872)
VIN = +5V TO +7V (MAX874)
-50
100
TEMPERATURE (°C)
SOURCE CURRENT (mA)
-20
-40
-50
MAX872/74-14
0.01
4.096
2.500
4.095
4.094
MAX872/74-12
2.504
4.097
4.100
MAX872/74-11
2.506
MAX872/74-10
4.098
MAX874
OUTPUT VOLTAGE vs. TEMPERATURE
MAX872
OUTPUT VOLTAGE vs. TEMPERATURE
MAX872/74-15
MAX874
OUTPUT VOLTAGE
vs. SOURCE CURRENT
PSRR (dB)
MAX872/MAX874
10µA, Low-Dropout,
Precision Voltage References
10k
-50
-25
0
25
50
TEMPERATURE (°C)
75
100
1
10
100
FREQUENCY (Hz)
MAX874
1Hz TO 100Hz NOISE
_______________________________________________________________________________________
1k
10k
10µA, Low-Dropout,
Precision Voltage References
PIN
NAME
FUNCTION
1, 7
I.C.
Internal Connection. Make no connection
to this pin
2
VIN
Input Voltage
3
TEMP
Temperature-Proportional Output
Voltage. Generates an output voltage
proportional to junction temperature.
4
GND
Ground
5
TRIM
Output Voltage Trim. Connect to the
center of a voltage divider for output
trimming. Otherwise make no
connection.
6
VOUT
Reference Output
COMP
Compensation Input. Connect
CLOAD/100 capacitor from VOUT to
COMP to provide capacitive load
compensation.
8
3V
VIN
MAX872/MAX874
Pin Description
VOUT
MAX872
TRIM
1M
1.5M
GND
TRIM RANGE: -35mV/+80mV
Figure 1a. Adjusting VOUT with the TRIM Input on the MAX872
Applications Information
Trimming the Output Voltage
The MAX872/MAX874’s output voltage is trimmed for
0.2% tolerance at +25°C. If additional VOUT trimming is
desired, connect a potentiometer to TRIM, as shown in
Figures 1a and 1b. Adjusting VOUT away from its factory-trimmed voltage typically changes the output voltage
tempco by 7ppm/°C per 100mV.
Reducing Input Ripple with an Input Filter
The Power-Supply Rejection Ratio vs. Frequency graph
in the Typical Operating Characteristics shows ripple
rejection between 10Hz and 2kHz. As input RC filter
with a pole less than 10Hz, as shown in Figure 2, further attenuates input ripple with this band. The voltage
drop across the input resistor (due to supply and load
current) slightly increases the dropout voltage. The
increase is given by [(ILOAD + ISUPPLY) • R].
Choosing the Output and
Compensation Capacitors
Connecting a capacitor between Void and GND
reduces load transients. If the load exceeds 300µA,
connect a minimum of 1000pF from VOUT to GND. The
type of capacitor is not critical. If the total load capacitance from VOUT to GND (CLOAD = output capacitor +
other capacitive load) is larger than 1000pF, connect a
compensation capacitor with a value of C LOAD/100
between COMP and VOUT.
5V
VIN
VOUT
2M
MAX874
TRIM
GND
1M
4M
TRIM RANGE: -200mV/+300mV
Figure 1b. Adjusting VOUT with the TRIM Input on the MAX874
_______________________________________________________________________________________
7
MAX872/MAX874
10µA, Low-Dropout,
Precision Voltage References
REF OUT
V+
3.0V (MAX872)
5.0V (MAX874)
170k (MAX872)
330k (MAX874)
+5V
VIN
150Ω
VIN
COMP
1/2
MAX922
VOUT
27k
100µF
MAX872
MAX874 V
OUT
0.047µF
MAX872
MAX874
TEMP OUT OF RANGE
TEMP
+5V
4.7µF
GND
OVER TEMP
1/2
MAX922
GND
1/4 74HC86
UNDER TEMP
54k
-40°C TO +85°C OPERATING RANGE
Figure 3. Operating Temperature Range Window Comparator
Figure 2. Input Filter Reduces Input Ripple
TEMP Output
___________________Chip Topography
The TEMP output provides a voltage proportional to the
MAX872/MAX874 junction temperature. Since the
power dissipation of the MAX872/MAX874 is <100µW
typ, the junction temperature is within 0.5°C of the
ambient temperature. Although it goes unused in most
applications, the ambient temperature information
given by the TEMP output may be used to control LCD
contrast, or to provide ADC gain compensation or thermal out-of-range indication. TEMP must be buffered or
connected to a high-impedance input.
Operating Temperature
Window Comparator
In Figure 3, a window comparator monitors the TEMP
output and indicates if the temperature is out of the
nominal operating range. For the resistor values shown,
the circuit will indicate an out-of-range condition if the
ambient temperature should rise above +85°C or dip
below -40°C.
MAX872/MAX874
*N.C. COMP
*N.C.
VIN
TEMP
OUT
GND
TRIM
0.110"
(2.794mm)
Start-Up
When the input voltage is below the factory-selected
output voltage, the MAX872/MAX874 can draw excessive supply current (hundreds of microamps). If the
source resistance is too high, the voltage drop across
the source resistance can prevent the input voltage to
the device from reaching the minimum dropout voltage.
Therefore, when using the MAX872/MAX874 in lowdropout applications, ensure that the power supply has
a low source resistance.
0.072"
(1.829mm)
*MAKE NO CONNECTIONS TO THESE PADS
TRANSISTOR COUNT: 89
SUBSTRATE CONNECTED TO GND.
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
8 _____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 1997 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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