Rev. 10/30/00
SPX431C
Precision Adjustable Shunt Regulator
FEATURES
APPLICATIONS
Wide Operating Current.........................1mA to 150mA
Battery Operating Equipments
Extended Termperature Range........................... 105C
Adjustable Supplies
Low Temperature Coeffecient 30 ppm/C
Switching Power Supplies
Offered in TO-92, SOT-89 & SOT-23-5 Packages
Error Amplifiers
Improved Replacement in Performance for TL431
Single Supply Amplifier
Low Cost Solution
Monitors / VCR / TV
Personal Computers
PRODUCT DESCRIPTION
The SPX431C is a 3-Terminal Adjustable Shunt Voltage Regulator providing a highly accurate bandgap reference. SPX431C acts as
an open-loop error amplifier with a 2.5V temperature compensation reference. The SPX431C thermal stability, wide operating current
(150mA) and temperature range (105
C) makes it suitable for all variety of applications that are looking for a low cost solution with
high performance.
The output voltage may be adjusted to any value between V
REF
and 36V with 2 external resistors. The SPX431C is operating in full
industrial temperature range of 0C to 105C. The SPX431C is available in TO-92, SOT-23-5 and SOT-89 packages.
PIN CONFIGURATION
2.5V
+
-
REFERENCE
(R)
CATHODE (K)
ANODE (A)
Bottom View
TO-92 (N)
1
3
2
CATHODE
ANODE
REF
SOT-23-5 (M5)
3
2
1
Top View
SPX431C
5
4
Top View
SPX431C
SOT-89 (M1)
1
2
3
REF
ANODE
CATHODE
REF
ANODE
CATHODE
N/C N/C
Rev. 10/30/00
SPX431C
ABSOLUTE MAXIMUM RATINGS
Parameter Symbol
Rating
Units
Cathode-Anode Reverse Breakdown
V
KA
37 V
Anode-Cathode Forward Current
I
AK
1 A
Operating Cathode Current
I
KA
150 mA
Reference Input Current
I
REF
10 mA
Continuous Power Dissipation at 25
C
TO-92
SOT-23
SOT-89
P
D
775
200
1000
mW
mW
mW
Junction Temperature
T
J
150 C
Storage Temperature
T
STG
- 65 to +150
C
Lead Temperature (Soldering 10 sec.)
T
L
30 C
Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional
operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect reliability.
RECOMMENDED CONDITIONS
TYPICAL THERMAL RESISTANCE
Parameter Symbol
Rating
Unit
Package
Type
JA
JC
Typical Derating
Cathode Voltage
V
KA
V
REF
to 20
V
TO-92
160
C/W 80C/W 6.3
mW/
C
Cathode Current
I
K
10
mA
SOT-23
575
C/W 150C/W 1.7
mW/
C
SOT-89
110
C/W 8C/W 9.1
mW/
C
ELECTRICAL CHARACTERISTICS
at 25C I
k
@ 10mA V
k
=V
ref
, unless otherwise specified.
Parameter Symbol
Test
Conditions
SPX431C
Unit
Min Typ Max
Reference Voltage
V
REF
T
A
= 25
C TC = 1
2.445 2.495 2.545 V
Ratio of Change in V
REF
to Cathode Voltage
V
REF
V
K
V
REF
to 10V
10V to 36V TC = 2
-2.7
-2
-1.0
-0.4
0.3
mV/V
Reference Input Current
I
REF
TC = 2
0.7
4
A
I
REF
Temp Deviation
I
REF
Over Temp. TC = 2
0.4
1.2
A
Min I
K
for Regulation
I
K(MIN)
TC = 1
0.4
1
mA
Off State Leakage
I
K(OFF)
V
REF
= 0V,
V
KA
= 36V TC=3
0.04 1 A
Dynamic Output Impedance
Z
KA
TC = 1
0.15
0.5
TC = Test Circuit
Rev. 10/30/00
SPX431C
*CALCULATING AVERAGE TEMPERATURE COEFFICEINT (TC)
TEST CIRCUITS
I
K
I
REF
V
IN
V
KA
= V
REF
V
IN
V
KA
I
K
R
1
R
2
(V
REF
)
TEST CIRCUIT
For V
KA
> V
REF
TEST CIRCUIT
For V
KA
= V
REF
V
IN
V
KA
I
K (OFF)
TEST CIRCUIT
For I
ROFF
I
REF
1G-38
1G-39
1G-40
T
V
REF
0
15
30
45
60
75
90
105
-10
0.5
5000
0
0
ppm
%
mV
0
0.07 mV/C
0.003 %/C
27 ppm/C
TC in mV/C =
TC in mV/C =
V
REF
(mV)
T
A
T
A
V
REF
at 25C
V
REF
x 100
(
)
TC in ppm/C =
T
A
V
REF
at 25C
V
REF
x 10
6
(
)
Rev. 10/30/00
SPX431C
TYPICAL PERFORMANCE CURVES
Low Current Operating Characteristics
900
800
700
600
500
400
300
200
100
0
-100
-200
1.0
-1.0
2.0
0
3.0
V
KA
- Cathode Voltage (V)
I
K
- Cathode Current (
A)
V
KA
= V
REF
Temperature Range: - 0 C to 125 C
105 C
25 C
-0C
Figure 2
V
KA
- Cathode Voltage (V)
-2
-1
0
1
2
3
-100
-75
-50
-25
0
25
50
75
100
125
150
High Current Operating Characteristics
Figure 3
I
K
- Cathode Current (mA)
V
KA
= V
REF
Temperature Range: - 0C to 125 C
Off State Leakage
-60
-30
0
30
60
90
120
0.01
0.1
1
10
100
Figure 4
T
A
- Ambient Temperature ( C)
I
Z
off - Off State Cathode Current (nA)
V
KA
= 36V
V
REF
= 0V
T
A
- Ambient Temperature ( C)
Figure 5
Reference Voltage vs. Ambient Temperature
V
R
EF
- Reference Voltage (V)
-60
-30
0
30
60
90
120
2.45
2.46
2.47
2.48
2.49
2.50
2.51
2.52
2.53
V
KA
= V
REF
I
K
= 10 mA
V
REF
= 2.500 V at 25 C
Rev. 10/30/00
SPX431C
TYPICAL PERFORMANCE CURVES
T
A
- Ambient Temperature ( C)
Figure 6
Reference Input Current
I
R
EF
- Reference Input Current (
A)
-60
-30
0
30
60
90
120
0
R1 = 10 k
R2 =
I
K
= 10 mA
0.5
1.0
1.5
2.0
2.5
3.0
Figure 7
Reference Voltage Line Regulation
V
KA
- Cathode Voltage (V)
V
KA
- Cathode Voltage (V)
0
-10
-20
-30
-40
-50
0
3
6
9
12
15
18
21
24
27
105 C
75 C
30
25 C
0 C
Noise Voltage
Figure 8
f - Frequency (Hz)
Noise Voltage nV/
Hz
70
20
30
40
10
50
60
10
100
1 k
10 k
100 k
0
T
A
- Free Air Temperature
Figure 9
Low Frequency Dynamic Output Impedance
Z
K
A
- Dynamic Impedance (
)
-60
-30
0
30
60
90
120
0.0
V
KA
= V
REF
I
KA
= 1 to 100 mA
f < 1 kHz
0.025
0.050
0.075
0.100
0.125
0.150
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