ADMOS AMS9491A

Advanced
Monolithic
Systems
AMS9491
1.235V VOLTAGE REFERENCE
FEATURES
APPLICATIONS
• ±10 mV max. initial tolerance (A grade)
• Operating Current 10µ
µ A to 20mA
• Low Voltage Reference 1.235
• Max. 0.6Ω
Ω Dynamic Impedance (A grade)
• Low Temperature Coefficient
• Battery Powered Systems
• Instrumentation
• A/D, D/A Converters
• Temperature measurement
• Current sources
• Pagers
GENERAL DESCRIPTION
The AMS9491 is a two-terminal micropower band-gap voltage reference diode. It feature a very low dynamic impedance and
good temperature coefficient, operating over a 10µA to 20mA current range. On-chip trimming is used to provide tight
voltage tolerance. Since the AMS9491 is a band-gap reference, uses only transistors and resistors, low noise and good longterm stability result. Careful design of the AMS9491 has made the device exceptionally tolerant of capacitive loading, making
it easy to use in almost any reference application. The wide dynamic operating range allows its use with widely varying
supplies with excellent regulation. The extremely low power drain of the AMS9491 makes this reference diode useful for
micropower circuitry.
The AMS9491 can be used to make portable meters, regulators or general purpose analog circuitry with battery life
approaching shelf life. Further more, the wide operating current allows it to replace older references with a tight tolerance
part.
The AMS9491 is operating over a 0°C to 70°C temperature range and is available in TO-92 and SO-8 packages.
ORDERING INFORMATION:
TOL.
PACKAGE TYPE
TO-92
±10mV AMS9491AN
±20mV AMS9491BN
OPERATING
TEMPERATURE RANGE
8 LEAD SOIC
AMS9491AS
AMS9491BS
0 to 70° C
0 to 70° C
PIN CONNECTIONS
TO-92
Plastic Package (N)
3
1
8L SOIC
SO Package (S)
+
8
1
N/C N/C N/C
7
6
5
2
3
N/C N/C N/C
Bottom View
4
-
Top View
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS9491
ABSOLUTE MAXIMUM RATINGS (Note 1)
Reverse Current
Forward Current
Operating Temperature Range
Storage temperature
30mA
10mA
0°C to 70°C
-55°C to +150°C
Soldering information
TO-92 package: 10 sec.
SOIC package: Vapor phase (60 sec)
Infrared (15 sec.)
300°C
215°C
220°C
ELECTRICAL CHARACTERISTICS
Electrical Characteristics at IR = 100 µA, and TA = +25°C unless otherwise specified.
Parameter
Conditions
Reverse Breakdown Voltage
(Note 4)
IR - 100 µA
Reverse Dynamic Impedance
(Note 4)
IR - 100 µA, f =20Hz
Reverse Breakdown Voltage
Change with current (Note 4)
10µA ≤IR ≤1mA
1mA ≤IR ≤20mA
AMS9491A
Max
Min
Typ
Max
1.215
1.235
1.255
1.215
1.235
1.255
V
0.2
0.6
0.2
0.6
Ω
2.0
20
mV
10
20
µA
2.0
20
8
IR - 100 µA,
10Hz ≤ f ≤ 10kHz
10
20
60
Temperature Coeff.
(Note 6)
Long Term Stability
(Note 5)
Units
Typ
Min. Operating Current (Note 4)
Wide Band Noise
(Note 5)
AMS9491B
Min
8
50
20
TA=25°C±.1°C
T = 1000 Hr
µV
60
100
20
ppm/°C
ppm
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
intended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics. The
guaranteed specifications apply only for the test conditions listed.
Note 2: Thermal resistance is as follows:
Thermal Resistance
ϕ JA (junction to ambient)
TO-92
170°C/W (0.125” leads)
SO-8
165°C/W
Note 3: Parameters identified with boldface type apply at temperature extremes. All other numbers apply at TA = TJ = 25°C.
Note 4: Guaranteed and 100% production tested.
Note 5: Guaranteed but not 100% production tested. These limits are not used to calculate average outgoing quality levels.
Note 6: The average temperature coefficient is defined as the maximum deviation of reference voltage at all measured temperatures between the operating TMAX and
TMIN, divided by TMAX - TMIN. The measured temperatures are 0°C, 25°C, 70°C.
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS9491
TYPICAL APPLICATIONS
Wide Input
Range Reference
Micropower Reference
from 9V Battery
Reference from
1.5V Battery
9V
VIN = 2.3V TO 30V
1.5V
500k
3k
LM334
1.2V
1.2V
4.3k
AMS9491
AMS9491
OUT
1.24V
AMS9491
0°°C - 100°°C Thermometer
0°°C - 100°°C Thermometer
Lower Power Thermometer
*
150
150
M
1.3 TO
1.6V‡
0-100µA M
8k TO
12k†
R1
4k
IOUT
R2
1k
V+
LM334
V-
LM334
R
AMS9491
LM334
AMS9491
R4
220
R1
2k
IOUT
R2
1k
V+
1.5V
(1.3-1.6V)†
R3
100
M
0-50µA
V-
* 2N3638 or 2N2907 select for inverse HFE ≅ 5
† Select for operation at 1.3V
‡ IQ ≅ 600µA to 900 µA
R
1.3-1.6V
AMS9491
R3
50
R4
100
Calibration
Calibration
1. Short AMS9491, adjust R3 for IOUT = temp at
1µA/°K
2. Remove short, adjust R2 for correct reading in °C
† IQ at 1.3V ≅ 500 µA
IQ at 1.6V ≅ 2.4mA
1. Short AMS9491, adjust R3 for IOUT = temp at
1.8µA/°K
2. Remove short, adjust R2 for correct reading in °F
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS9491
TYPICAL APPLICATIONS (Continued)
Centigrade Thermometer
Micropower* 10V Reference
IQ
VIN = 15V
2.2k
+
V
LM334
V1
R
V-
2.3k
1.5V†
V2
90k
25k
1M
OUTPUT
1mV/° C
2
7
+
6
LM4250C
3
27k
1.2k
10V
8
4
AMS9491
22M
150pF
R1
1k
3.5M
500k
AMS9491
*IQ ≅ 20µA standby current
Calibration
1. Adjust R1 so that V1 = temp at 1mV/°K.
2. Adjust V2 to 273.2mV.
† IQ for 1.3V to 1.6V battery voltage = 50µA to 150µA
Micropower Thermocouple Cold Junction Compensator
V+
5.1k
LM334
1M
1%
R
VMERCURY
+
CELL
1.345V
ZERO ADJ
100k
AMS9491
R2
2k
1%
Adjustment Procedure
TC ADJ
500
1. Adjust TC ADJ pot until voltage across R1 equals Kelvin temperature
multiplied by the thermocouple Seebeck coefficient.
2. Adjust ZERO ADJ pot until voltage across R2 equals the thermocouple
Seebeck coefficient multiplied by 273.2.
R1
Thermocouple
Type
+
THERMOCOUPLE
+
METER
COLD JUNCTION
ISO THERMAL
WITH LM334
J
T
K
S
Seebeck
Coefficient
(mV/ ° C)
R1
(Ω
Ω)
R2
Voltage
Voltage
(Ω
Ω ) Across R1
Across R2
@ 25°°C (mV)
(mV)
52.3
42.8
40.8
6.4
523
432
408
63.4
1.24k
1k
953Ω
150Ω
15.60
12.77
12.17
1.908
14.32
11.78
11.17
1.766
Typical supply current 50µA
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS9491
TYPICAL APPLICATIONS (Continued)
Precision 1µ
µ A to 1mA Current Sources
AMS9491
AMS9491
30V
C1
150pF
R1
100k
2
R1
100k
-
+
2
7
-
6
LM312
3
C1
150pF
4
IOUT*
7
6
LM312
3
IOUT*
R2
-1.5V TO -27V
+
4
R2
1.5V TO 27V
-30V
*IOUT =1.23V/R2
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS9491
TYPICAL PERFORMANCE CHARACTERISTICS
Reverse Characteristics
TA =125° C
6
4
TA =25° C
2
TA =-55° C
0
10
T A =125° C
TA =-55° C
1
TA =25° C
0.1
-2
0.1
1
10
REVERSE CURRENT (mA)
TA =25° C
TA =-55° C
Reverse Dynamic Impedance
1.250
1.240
1.230
1.220
100
SHARP CUTOFF
FILTER
1.5
VOLTAGE SWING (V)
AMS9491
NOISE (nV/√Hz)
100µA
20
0
100
10
10k
100k
1k
FREQUENCY (Hz)
1M
IR= 100 µA
40
10
1
2.0
600
SINGLE POLE LOW PASS
OUTPUT
30
10
Response Time
700
IR= 100 µA
50
100
Noise Voltage
Filtered Output Noise
70
60
T A =25° C
I R= 100 µA
1k
0.1
-55 -35 -15 5 25 45 65 85 105 125
TEMPERATURE (° C)
100
0.1
1
10
100
FORWARD CURRENT (mA)
10k
I R= 100 µA
0.1
0.1
1
10
REVERSE CURRENT (mA)
TA =125° C
0.01
DYNAMIC IMPEDANCE (Ω)
REFERENCE VOLTAGE (V)
TA =125° C
0.01
T A =25° C
0.4
0.2 0.4 0.6 0.8 1.0 1.2 1.4
REVERSE VOLTAGE (V)
1.260
1
0.8
Temperature Drift of 3
Representative Units
100
10
TA =-55° C
0
0
100
Reverse Dynamic Impedance
DYNAMIC IMPEDANCE (Ω)
1.2
FORWARD VOLTAGE (V)
8
0.01
INTEGRATED NOISE (µV)
Forward Characteristics
100
REVERSE CURRENT (µA)
OUTPUT VOLTAGE CHANGE (mV)
Reverse Characteristics
10
500
400
300
200
1.0
100k
0.5
0
OUTPUT
~
~
~
~
10
INPUT
100
0
1k
10k
100k
CUTOFF FREQUENCY (Hz)
OUTPUT
INPUT
0
10
100
1k
10k
FREQUENCY (Hz)
100k
0
200
400
TIME (µs)
600
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140
AMS9491
PACKAGE DIMENSIONS inches (millimeters) unless otherwise noted.
3 LEAD TO-92 PLASTIC PACKAGE (N)
0.180±0.005
(4.572±0.127)
0.060±0.005
(1.524±0.127)
DIA
0.060±0.010
(1.524±0.254)
0.90
(2.286)
NOM
0.180±0.005
(4.572±0.127)
0.140±0.010
(3.556±0.127)
5° NOM
0.500
(12.70)
MIN
0.050
(1.270)
MAX
UNCONTROLLED
LEAD DIMENSIONS
0.015±0.002
(0.381±0.051)
0.016±0.003
(0.406±0.076)
0.050±0.005
(1.270±0.127)
10°
NOM
N (TO-92 ) AMS DRW# 042391
8 LEAD SOIC PLASTIC PACKAGE (S)
0.189-0.197*
(4.801-5.004)
8
7
6
5
0.228-0.244
(5.791-6.197)
0.150-0.157**
(3.810-3.988)
1
2
3
4
0.010-0.020
x 45°
(0.254-0.508)
0.053-0.069
(1.346-1.752)
0.004-0.010
(0.101-0.254)
0.014-0.019
(0.355-0.483)
0.008-0.010
(0.203-0.254)
0.050
(1.270)
TYP
0°-8° TYP
0.016-0.050
(0.406-1.270)
S (SO-8 ) AMS DRW# 042293
*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
Advanced Monolithic Systems, Inc. 6680B Sierra Lane, Dublin, CA 94568 Phone (925) 556-9090 Fax (925) 556-9140