CALOGIC CL431

Precision Adjustable
Shunt Reference
CORPORATION
CL431
FEATURES
DESCRIPTION
•
•
•
•
•
•
The CL431 is an adjustable shunt regulator designed to act as
an open-loop error amplifier with a 2.5V temperature
compensated reference. Its highly accurate 0.5% bandgap
reference is perfect for applications requiring stability and
accuracy over temperature and life.
Trimmed 0.5% Bandgap Reference
Nominal Temperature Range Extended to 105oC
Temperature-Compensated: 30ppm/ oC
Internal Amplifier with 150mA Capability
Low Output Noise
Low Frequency Dynamic Output Impedance
Sharp turn-on characteristics and a low temperature
coefficient make the CL431 an excellent replacement for
many zener diode applications, programmable to any value
greater than 2.5V and up to 36V by using two external
resistors. As a combination error amplifier and reference, it
can be used to manage control loops such as switching power
supplies.
The CL431 can be used as a direct replacement for the
standard TL431.
ORDERING INFORMATION
Part
Package
CL431LP
CL431D
CL431S
TO-92
8-Pin Plastic SOIC
SOT-89
Temperature Range
0 to 105oC
0 to 105oC
0 to 105oC
PIN CONFIGURATION (Top View)
SOIC (D)
TO-92 (LP)
SOT-89 (S)
CATHODE
1
8
REFERENCE
ANODE
2
7
ANODE
ANODE
3
6
ANODE
N/C
4
5
N/C
CATHODE
ANODE
REFERENCE
CATHODE
ANODE
REFERENCE
1G-34
1G-33
1G-35
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CL431
CORPORATION
ABSOLUTE MAXIMUM RATINGS
SYMBOL
PARAMETER
RATING
UNITS
VKA
Cathode-Anode Reverse Breakdown
37
V
IAK
Anode-Cathode Forward Current
1
A
IKA
Operating Cathode Current
250
mA
IREF
Reference Input Current
10
mA
PD
Continuous Power at 25 oC
TO-92
8L SOIC
SOT-89
775
750
1000
mW
mW
mW
TJ
Junction Temperature
150
o
C
TSTG
Storage Temperature
–65 to 150
o
C
TL
Lead Temperature, Soldering 10 Seconds
300
o
C
Exceeding ABSOLUTE MAXIMUM RATINGS may cause permanent damage. Extended operation of the device at these or any other conditions
above those indicated in the operational sections of this specification is not recommended as it may adversely affect reliability and performance.
RECOMMENDED CONDITIONS
SYMBOL
TYPICAL THERMAL RESISTANCE
PARAMETER
RATING
UNIT
PACKAGE
θJA
o
θJC
o
TYPICAL DERATING
VKA
Cathode Voltage
VREF to 20
V
TO-92
160 C/W
80 C/W
6.3mW/oC
IK
Cathode Current
10
mA
SOIC
175 oC/W
45 oC/W
5.7mW/oC
SOT-89
110oC/W
8oC/W
9.1mW/oC
FUNCTIONAL BLOCK DIAGRAM
CATHODE (K)
REFERENCE (R)
+
–
2.5V
ANODE (A)
1G-36
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CL431
CORPORATION
ELECTRICAL CHARACTERISTICS
Electrical Characteristics are guaranteed over full junction temperature range (0 to 105oC). Ambient temperature must be derated based on
power dissipation and package thermal characteristics. The conditions are: VKA = VREF and IK = 10mA unless otherwise stated.
SYMBOL
CL431 (0.5%)
PARAMETER
VREF
Reference Voltage
V
1
TA = 25oC
2.536
V
1
Over Temp.
2.490
2.503
0.07
Ratio of Change in VREF to
Cathode Voltage
2.515
MAX
∆VREF with Temp.*
∆VREF
∆VK
TEST
CIRCUIT
TYP
2.469
TC
UNIT
MIN
–2.7
–1.0
–2
–0.4
0.20
o
mV/ C
1
mV/V
2
TEST CONDITION
VREF to 10V
0.3
10V to 36V
IREF
Reference Input Current
0.7
4
µA
2
∆IREF
IREF Temp Deviation
0.4
1.2
µA
2
IK(MIN)
Min I K for Regulation
0.4
1
mA
1
IK(OFF)
Off State Leakage
0.04
250
nA
3
VREF = 0V, VKA = 36V
ZKA
Dynamic Output Impedance
0.15
0.5
Ω
1
f ≤ 1kHz, IK = 1 to 150mA
Over Temp.
mV
ppm
*CALCULATING AVERAGE TEMPERATURE COEFFICIENT (TC)
%
0
0
• TC in mV/oC =
0
∆VREF
∆T
–10
5000
0.5
• TC in %/oC =
0
15
30
45
60
75
90
∆VREF (mV)
∆TA
∆VREF



o 
 VREF at 25 C 
105
TEMPERATURE (˚C)
o
• TC in ppm/ C =
0.07 mV/˚C
x 100
∆TA
∆VREF



o 
 VREF at 25 C 
x 106
∆TA
0.003 %/˚C
27 ppm/˚C
1G-37
TEST CIRCUITS
V IN
V KA = V REF
V IN
V KA
IK
IK
I REF
R1
V IN
V KA
I K(OFF)
I REF
(V REF )
R2
1G-38
1G-39
TEST CIRCUIT 1
TEST CIRCUIT 2
1G-40
TEST CIRCUIT 3
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CL431
CORPORATION
TYPICAL PERFORMANCE CURVES
TEMPERATURE RANGE: –55 to 125˚C
700
600
500
400
125˚C
300
25˚C
200
–55˚C
100
0
–100
–200
–1.0
0
1.0
2.0
3.0
VKA – CATHODE VOLTAGE (V)
1G-41
10
1
0.1
75
50
25
0
–25
–50
–75
–1
0
1
2
VKA – CATHODE VOLTAGE (V)
3
1G-42
VKA = VREF
2.53 I K = 10mA
2.52
2.51
2.50
VREF = 2.503V AT 25˚C
2.49
2.48
2.47
2.46
–60
1G-43
REFERENCE
INPUT CURRENT
2.0
1.5
1.0
0.5
–10
1G-44
–55˚C
0˚C
–20
25˚C
75˚C
–30
125˚C
–40
I K = 10mA
–50
TEMPERATURE RANGE: –55 to 125˚C
0
1G-45
–30
0
30
60
90 120
TA – AMBIENT TEMPERATURE
REFERENCE VOLTAGE
LINE REGULATION
0
R1 = 10kΩ
R2 = ∞
2.5 I K = 10mA
0
0
30
60
90 120
–60 –30
TA – AMBIENT TEMPERATURE (˚C)
100
2.54
VKA = 36V
VREF = 0V
3.0
VKA = VREF
TEMPERATURE RANGE: –55 to 125˚C
TEMPERATURE COEFFICIENT AS
A FUNCTION OF TRIM VALUE
OFF STATE LEAKAGE
0.01
0
30
60
90 120
–60 –30
TA – AMBIENT TEMPERATURE (˚C)
125
HIGH CURRENT OPERATING
CHARACTERISTICS
–100
–2
VREF – REFERENCE VOLTAGE (V)
I Z off – OFF STATE CATHODE
CURRENT (nA)
100
I REF – REFERENCE INPUT
CURRENT (µA)
150
VKA = VREF
I K – CATHODE CURRENT (mA)
800
VREF – CHANGE IN REFERENCE
VOLTAGE (mV)
I K – CATHODE CURRENT (µA)
900
LOW CURRENT OPERATING
CHARACTERISTICS
3 6 9 12 15 18 21 24 27 30
VKA – CATHODE VOLTAGE (V)
1G-46
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CL431
CORPORATION
TYPICAL PERFORMANCE CURVES (continued)
NOISE VOLTAGE
0.150
Z KA – DYNAMIC IMPEDANCE (Ω)
NOISE VOLTAGE nV/ Hz
70
60
50
40
30
20
VKA = VREF
10 I K = 10mA
TA = 25˚C
0
100
1k
10k
10
f – FREQUENCY (Hz)
Z KA – DYNAMIC IMPEDANCE (Ω)
A V – SMALL SIGNAL VOLTAGE
GAIN (dB)
VKA = VREF
I KA = 1 TO 100mA
f ≤ 1kHz
0.100
0.075
0.050
0.025
0.0
–60
1G-47
–30
0
30
60
90 120
TA – FREE AIR TEMPERATURE
1G-48
DYNAMIC OUTPUT
IMPEDANCE
TA = 25˚C
I K = 1 TO 100mA
10
1.0
0.1
0.01
1k
70
0.125
100k
100
LOW FREQUENCY DYNAMIC
OUTPUT IMPEDANCE
10k
100k
1M
f – FREQUENCY (Hz)
10M
1G-49
SMALL SIGNAL GAIN
vs FREQUENCY
OUT
60
50
15k
TA = 25˚C
I K = 10mA
9µF
IK
230Ω
40
30
8.25k
GND
20
1H-01
10
0
1k
10k
100k
1M
f – FREQUENCY (Hz)
10M
1G-50
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025
CL431
CORPORATION
INPUT AND OUTPUT VOLTAGES (V)
TYPICAL PERFORMANCE CURVES (continued)
6
PULSE RESPONSE
INPUT
INPUT
MONITOR
5
220Ω
OUT
4
3
OUTPUT
50Ω
f P = 100kHz
2
1
GND
0
1H-03
–1
0 1 2 3 4 5 6 7 8 9 10 11 12
t – TIME (µs)
1H-02
I K – CATHODE CURRENT (mA)
100
90
80
STABILITY BOUNDARY
CONDITIONS
A: VKA = VREF
150 Ω
B: VKA = 5V AT I K = 10mA
C: VKA = 10V AT I K = 10mA
D: VKA = 15V AT I K = 10mA
IK
70
60
50
STABILITY
REGION
C
40
10k
30
A
20
10
CL
B
TA = 25˚C
1H-05
D
0
100 101 102 103 104 105 106 107
C L – LOAD CAPACITANCE (pF)
1H-04
CALOGIC CORPORATION, 237 Whitney Place, Fremont, California 94539, Telephone: 510-656-2900, FAX: 510-651-3025