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MI
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://www.m
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une 10, 2003
MIK431
ADJUSTABLE PRECISION SHUNT REGULATOR
DATA SHEET
J
UNE
10, 2003
N
O
. 00008
R
EV
1-03
CONTENTS
Page
GENERAL DESCRIPTION
1
FEATURES
1
REPRESENTATIVE SCHEMATIC DIAGRAM
2
SYMBOL & BLOCK DIAGRAM
2
ABSOLUTE MAXIMUM RATINGS
2
RECOMMENDED OPERATING CONDITIONS
2
ELECTRICAL CHARACTERISTICS
3
TYPICAL CHARACTERISTICS
4
REFERENCE VOLTAGE versus FREE-AIR
TEMPERATURE
4
REFERENCE CURRENT versus FREE-AIR
TEMPERATURE
4
CATHODE CURRENT versus CATHODE
VOLTAGE (1)
4
CATHODE CURRENT versus CATHODE
VOLTAGE (2)
4
OFF-STATE CATHODE CURRENT versus FREE-
AIR TEMPERATURE
4
RATIO OF DELTA REFERENCE VOLTAGE TO
DELTA CATHODE VOLTAGE versus FREE-AIR
TEMPERATURE
4
SMALL-SIGNAL VOLTAGE AMPLIFICATION
versus FREQUENCY
5
REFERENCE IMPEDANCE versus FREQUENCY
5
PULSE RESPONSE
5
STABILITY BOUNDARY CONDITIONS
6
PARAMETER MEASUREMENT INFORMATION
6
TEST CIRCUIT FOR V
KA
= V
REF
TEST CIRCUIT FOR V
KA
> V
REF
6
TEST CIRCUIT FOR I
OFF
6
APPLICATION INFORMATION
7
SHUNT REGULATOR
7
SINGLE-SUPPLY COMPARATOR WITH
TEMPERATURE--COMPENSATED THRESHOLD
7
CONTENTS
Page
PRECISION HIGH-CURRENT SERIES
REGULATOR
7
OUTPUT CONTROL OF A THREE-TERMINAL
FIXED REGULATOR
7
HIGH-CURRENT SHUNT REGULATOR
7
CROWBAR CIRCUIT
7
PRECISION 5-V 1.5-A REGULATOR
7
EFFICIENT 5-V PRECISION REGULATOR
7
PWM CONVERTER WITH REFERENCE
7
VOLTAGE MONITOR
7
DELAY TIMER
7
PRECISION CURRENT LIMITER
7
PRECISION CONSTANT-CURRENT SINK
8
OUTPUT CONTROL FOR A THREETERMINAL
FIXED REGULATOR
8
SERIES PASS REGULATOR
8
LINEAR OHMMETER
8
SIMPLE 400 mW PHONO AMPLIFIER
8
OVER VOLTAGE/UNDER VOLTAGE
PROTECTION CIRCUIT
8
HIGH EFFICIENCY STEPDOWN SWITCHING
CONVERTER
8
FLYBACK WITH ISOLATION USING MIK431
AS VOLTAGE REFERENCE AND ERROR
AMPLIFIER
8
PHYSICAL DIMENSIONS AND MARKING
DIAGRAMS
9
SOT-23-3
9
SOT-89
9
TO-92
9
ORDERING INFORMATION
10
GENERAL DESCRIPTION
The MIK431 is three-terminal adjustable shunt
regulator with specified thermal stability. The output
voltage may be set to any value between V
REF
(approximately 2.5V) and 36V with two external
resistors. These devices have a typical output
impedance of 0.2
. Active output circuitry provides a
very sharp turn-on characteristic, making the MIK431
an excellent replacement for Zener diodes in many
applications.
FEATURES
Equivalent full-range temperature coefficient
30 ppm/C.
Temperature compensated for operation over full
rated operating temperature range.
Adjustable output voltage.
Fast turn-on response.
Sink current capability 1mA to 100 mA.
Low (0.2
typ.) dynamic output impedance.
Low output noise.
REPLACEMENT
of
AS431
LM431
TL431
SC431
MIK431
ADJUSTABLE PRECISION SHUNT REGULATOR
2
Design by Vladimir F.Lityaghin / E-mail: lityaghin@mail.ru / Tel: +7(095)532-64-54
MI
K
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ON J
S
C
ht
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p
://www.m
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k
r
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n
.
r
u
J
une 10, 2003
ADJUSTABLE PRECISION SHUNT REGULATOR
MIK431
RECOMMENDED OPERATING CONDITIONS
TO-92
MIK431xCZ
Note 1: Voltage values are with respect to the anode terminal unless otherwise noted.
ABSOLUTE MAXIMUM RATINGS
OVER OPERATING FREE-AIR TEMPERATURE RANGE, UNLESS
OTHERWISE NOTED.
SOT-23-3
MIK431xCM3
SOT-23-3
Top View
1-- Reference
2-- Anode
3-- Cathode
SOT-89
Top View
1-- Reference
2-- Anode
3-- Cathode
tab-- Anode
TO-92
Top View
1-- Reference
2-- Anode
3-- Cathode
1
2
3
SOT-89
MIK431xCM2
REPRESENTATIVE SCHEMATIC DIAGRAM
3
2
1
CATHODE
K
A
ANODE
REFERENCE
R
!
! !
!
!
!
!
!
!
!
! !
!
!
!
!
!
!
!
!
!
!
!
!
!
! !
3
2
tab
1
SYMBOL
R
R
EFERENCE
K
C
ATHODE
A
A
NODE
BLOCK DIAGRAM
CATHODE
K
A
ANODE
REFERENCE
R
2.5 V
REF
!
! !
!
!
SYMBO
L
PARAMETER
MIN
MAX
UNIT
V
KA
Cathode voltage
V
ref
36 V
I
K
Cathode current (for regulation )
1
100
mA
SYMBOL
PARAMETER
MAXIMUM
UNIT
V
KA
Cathode voltage (Note 1)
37 V
I
K
Continuous cathode current range
-100 to 150
mA
I
REF
Reference input current range
-50
A to 10mA
Operating free-air temperature range
0 to 70
C
Lead temperature 1.6mm from case for 10 seconds
260
C
3
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MI
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une 10, 2003
MIK431
ADJUSTABLE PRECISION SHUNT REGULATOR
ELECTRICAL CHARACTERISTICS
Electrical characteristics at 25C free-air temperature (unless otherwise noted)
Because minimum V
ref
occurs at the lower temperature, the coefficient is positive.
CALCULATING DYNAMIC IMPEDANCE
The dynamic impedance is defined as:
When the device is operating with two external resistors (see Figure 3), the total dynamic impedance of the
circuit is given by:
The deviation parameters
V
REF(dev)
and I
REF(dev)
are defined as the differences between the maximum and
minimum values obtained over the recommended temperature range. The average full-range temperature
coefficient of the reference voltage,
V
REF
, is defined as:
where:
T
A
is the recommended operating free-air temperature range of the device.
V
REF
can be positive or negative, depending on whether minimum V
REF
or maximum V
REF
, respectively,
occurs at the lower temperature.
Example: maximum V
REF
= 2496 mV at 30
C, minimum V
REF
= 2492 mV at 0
C, V
REF
= 2495 mV at 25
C,
T
A
= 70
C for MIK431C
C
ppm
23
C
70
10
mV
2495
mV
4
6
=
VREF
KA
KA
I
V
=
+
=
2
1
1
'
R
R
Z
I
V
Z
KA
A
REF
I
REF
T
V
V
V
10
C
25
at
C
ppm
6
(dev)
=
Maximum V
REF
Minimum V
REF
V
I (dev)
T
A
SYMBOL
PARAMETER
TE
S
T
CI
RCUI
T
TEST CONDITIONS
MIN
TYP
MAX
UNIT
V
KA
=V
REF
, l
K
=10mA
MIK431C (0.5%)
2487 2500 2513
MIK431B (1.0%)
2474 2500 2526
V
REF
Reference input voltage
1
MIK431A (2.0%)
2450 2500 2550
mV
V
REF
(dev)
Deviation of reference
input voltage over full
temperature range
1
V
KA
=V
REF
, l
K
=10mA,
T
A
=full range
4 17 mV
V
KA
=10V to V
REF
-2,7 -1.0
V
REF
/
V
KA
Ratio of change in
reference input voltage to
the change in cathode
voltage
2 l
K
=10mA
V
KA
=36V to 10V
-2 -0.4
mV
V
I
REF
Reference input current
2 l
K
=10mA, R1=10K
, R2=
0.7 4
l
REF (dev)
Deviation of reference
input current over full
temperature range
2
l
K
=10mA, R1=10K
, R2=
,
T
A
=full range
0.4 1.2
A
I
min
Minimum cathode current
for regulation
1 V
KA
=V
REF
0.4 1.0 mA
L
OFF
Off-state cathode current
3 V
KA
=36V, V
REF
=0
0.1 1.0
A
I Z
K
l
Dynamic impedance
1
V
KA
=V
REF
, l
K
=1mA to 100mA,
f
1KHz
0.2 0.5
4
Design by Vladimir F.Lityaghin / E-mail: lityaghin@mail.ru / Tel: +7(095)532-64-54
MI
K
R
ON J
S
C
ht
t
p
://www.m
i
k
r
o
n
.
r
u
J
une 10, 2003
ADJUSTABLE PRECISION SHUNT REGULATOR
MIK431
REFERENCE VOLTAGE versus FREE-AIR TEMPERATURE
REFERENCE CURRENT versus FREE-AIR TEMPERATURE
CATHODE CURRENT versus CATHODE VOLTAGE (1)
CATHODE CURRENT versus CATHODE VOLTAGE (2)
OFF-STATE CATHODE CURRENT
versus FREE-AIR TEMPERATURE
RATIO OF DELTA REFERENCE VOLTAGE TO
DELTA CATHODE VOLTAGE
versus FREE-AIR TEMPERATURE
--1
1
2
3
--200
200
400
600
800
0
0
TYPICAL CHARACTERISTICS
T
A
-- FREE-AIR TEMPERATURE (C)
V
RE
F
--
RE
F
E
RE
N
C
E
V
O
LTAGE
(m
V)
2600
2580
2480
2560
2460
2540
2440
2520
2420
2500
2400
--75 --50 --25
25
50
75 100 125
0
*
Data is for devices having the indicated value of V
REF
at
I
KA
= 10 mA, T
A
= 25C
I
RE
F
--
RE
F
E
RE
N
C
E
CU
RRE
N
T
(A
)
V
REF
= 2500 mV
*
V
KA
= V
REF
I
KA
= 10mA
0.5
0.7
0.9
1.1
--75 --50 --25
25
50
75 100 125
0
0
T
A
-- FREE-AIR TEMPERATURE (C)
R1 = 10.0k
R2 =
I
KA
= 10mA
--1
1
2
3
--2
--100
--75
--50
--25
25
50
75
100
125
150
0
0
I
KA
-- CATH
O
D
E
CU
RRE
N
T
(m
A
)
V
KA
-- CATHODE VOLTAGE (V)
V
KA
= V
REF
T
A
= 25C
V
KA
-- CATHODE VOLTAGE (V)
I
KA
-- CATH
O
D
E
CU
RRE
N
T
(A
)
V
KA
= V
REF
T
A
= 25C
0.5
1.5
2.5
2.0
1.0
--75 --50 --25
25
50
75 100 125
0
0
I
OF
F
-- O
F
F
-
STATE
CA
TH
O
D
E
CU
RRE
N
T
(A
)
T
A
-- FREE-AIR TEMPERATURE (C)
V
KA
= 36V
V
REF
= 0V
--75
--1.45
--1.35
--1.25
--1.15
--1.05
--0.95
--0.85
--50 --25
25
50
75 100 125
0
T
A
-- FREE-AIR TEMPERATURE (C)
V
RE
F
/
V
KA
(m
V / V)
V
KA
= 3V to 36V
I
min
5
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MI
K
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ON J
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p
://www.m
i
k
r
o
n
.
r
u
J
une 10, 2003
MIK431
ADJUSTABLE PRECISION SHUNT REGULATOR
TYPICAL CHARACTERISTICS
(CONTINUED)
SMALL-SIGNAL VOLTAGE AMPLIFICATION versus
FREQUENCY
TEST CIRCUIT FOR VOLTAGE AMPLIFICATION
REFERENCE IMPEDANCE versus FREQUENCY
TEST CIRCUIT FOR REFERENCE IMPEDANCE
PULSE RESPONSE
TEST CIRCUIT FOR PULSE RESPONSE
"
"
10
20
30
40
50
60
1k
10k
100k
1M
10M
0
f -- FREQUENCY (Hz)
A
V
--
SM
AL
L-
SIGN
AL V
O
LTA
G
E
AM
P
L
IF
ICATI
O
N
(d
B)
I
KA
= 10mA
T
A
= 25C
0.1
1
10
100
1k
10k
100k
1M
10M
f -- FREQUENCY (Hz)
|Z
KA
| --
RE
F
E
RE
N
C
E
I
M
P
E
D
A
N
C
E
(
)
1
0
0
--1
1
2
3
4
5
6
7
2
3
4
5
6
IN
P
U
T
AN
D
OU
T
P
U
T
VOL
T
A
G
E
(V)
t -- TIME (s)
I
KA
= 10mA
T
A
= 25C
T
A
= 25C
INPUT
OUTPUT
"
#
#
#
#
#
#
50
220
OUTPUT
GND
PULSE
GENERATOR
f = 100 kHz
I
KA
#
#
#
#
#
#
#
#
$
232
8.25 k
9F
15 k
OUTPUT
GND
I
KA
#
#
#
#
#
#
$
50
OUTPUT
GND
1k
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