AHK432
Adjustable Low Voltage Shunt Regulator
General Description
The AHK432 is a low voltage adjustable shunt refer-
ence with thermal stability guaranteed over the full
industrial temperature range. This three-terminal
regulator has an output voltage range that extends
from V
REF
(1.24V) to 20V, giving designers out-
standing flexibility in the development of power sup-
plies and instrumentation. With a low operating cur-
rent of 60µA, the AHK432 is well suited for battery-
powered portable electronic applications. It also has
a sharp turn-on characteristic and a dynamic resist-
ance of only 50mΩ, making it an excellent replace-
ment for zener diodes in low tempco designs.
The AHK432 is available in the Pb-free, surface-
mount 3- or 5-pin SOT23, as well as the through
hole TO-92. Three voltage tolerance options are
offered in each package: ±0.5%, ±1%, and ±2%.
Features
•
•
•
•
•
•
PowerManager
™
Wide Output Voltage Range (1.24V to 20V)
Operating Current From 60µA to 100mA
Low Dynamic Output Resistance of 50mΩ
±0.5% Trimmed Voltage Reference
10mV (Typical) V
REF
Deviation, From -40°C to
+105°C
Surface Mount 3- or 5-Pin SOT23 or Through-
Hole 3-Pin TO-92 Package
Applications
•
•
•
•
•
•
•
Adjustable and Programmable Supplies
Global Voltage Reference for Multiple Power
Supplies
Instrumentation
Isolated Feedback in Switching Power
Supplies
Linear Regulators (External Reference)
Medical Electronics (see Endnote, page 10)
Notebook Computers
Typical Application
IN
R
L
OUT
R1
Adjustable regulator:
AHK432
R2
OUT = V
REF
R1 + R2
R2
432.2005.11.1.3
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AHK432
Adjustable Low Voltage Shunt Regulator
Absolute Maximum Ratings
1
T
A
= 25°C, unless otherwise noted.
Symbol
V
Z
I
Z
I
REF
T
J
T
LEAD
Description
Cathode Voltage
Continuous Cathode Current
Reference Current
Operating Junction Temperature Range
Maximum Soldering Temperature (at Leads)
Value
20
100
3
-40 to 150
260
Units
V
mA
mA
°C
°C
Thermal Characteristics
Symbol
Θ
JA
P
D
Description
Maximum Thermal Resistance
Maximum Power Dissipation
Package
TO-92
SOT23-3, SOT23-5
TO-92
SOT23-3, SOT23-5
Value
160
410
780
300
Units
°C/W
mW
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi-
tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
432.2005.11.1.3
3
AHK432
Adjustable Low Voltage Shunt Regulator
Electrical Characteristics
T
A
= 25°C, unless otherwise noted.
AHK432 0.5%
AHK432 1.0%
AHK432 2.0%
Symbol
V
REF
Description Conditions
Min Typ Max Min Typ Max Min Typ Max Units
V
DEV
∆V
REF
/
∆V
Z
I
REF
I
REF(DEV)
I
Z(OFF)
R
Z
I
Z(MIN)
V
Z
= V
REF
T
A
= 25°C 1.234 1.240 1.246 1.228 1.240 1.252 1.215 1.240 1.265
Reference
I
Z
= 10mA
V
1.258 1.215
1.265 1.200
1.280
Voltage
(test circuit 1) T
A
= -40 1.222
to +105°C
T
A
= -40°C to +105°C,
10
25
10
25
10
25
mV
V
REF
Temp
V
Z
= V
REF
, I
Z
= 10mA
Deviation
(test circuit 1)
Ratio of Change I
Z
= 10mA,
-1.0 -2.7
-1.0 -2.7
-1.0 -2.7 mV/V
in V
REF
to
∆V
Z
= 16V to V
REF
Change in
(test circuit 2)
Cathode Voltage
Reference
R1 = 10kΩ, R2 =
∞,
0.15 0.5
0.15 0.5
0.15 0.5
µA
Input Current I
Z
= 10mA (test circuit 2)
I
REF
Temp
T
A
= -40°C to +105°C
0.1
0.4
0.1
0.4
0.1
0.4
µA
Deviation
R1 = 10kΩ, R2 =
∞,
I
Z
= 10mA (test circuit 2)
Off State
V
REF
= 0V
V
Z
= 6V
0.04 0.1
0.04 0.1
0.04 0.1
µA
Cathode Current (test circuit 3) V
Z
= 16V
0.04 0.5
0.04 0.5
0.04 0.5
Dynamic
f <1kHz, V
Z
= V
REF
,
0.05 0.2
0.05 0.2
0.05 0.2
Ω
Output
I
Z
= 100µA to 100mA
Impedance
(test circuit 1)
Minimum
V
Z
= V
REF
(test circuit 1)
60
80
60
80
60
80
µA
Operating
Current
4
432.2005.11.1.3
AHK432
Adjustable Low Voltage Shunt Regulator
Typical Characteristics
Unless otherwise noted, T
A
= 25°C, I
Z
= 10mA.
Cathode Current vs. Cathode Voltage
15
Cathode Current vs. Cathode Voltage
200
Cathode Current (µA)
-1
-0.5
0
0.5
1
1.5
Cathode Current (mA)
10
5
0
-5
-10
-15
150
100
50
0
-50
-100
-150
-200
-1
-0.5
0
0.5
1
1.5
Cathode Voltage ( V)
Cathode Voltage (V)
Reference Voltage vs. Temperature
1.252
180
Reference Current vs. Temperature
Reference Voltage (V )
1.248
1.244
1.24
1.236
1.232
-50
-25
0
25
50
75
100
125
Reference Curre nt (nA)
I
Z
= 10mA
160
140
120
100
80
60
40
20
0
-50
-25
0
25
50
75
I
Z
= 10mA
R
1
= 10kΩ
R
2
= Open
100
125
Junction Temperature (°C)
Junction Temperatur e (°C)
Cathode Current vs. Temperature
80
Ratio of
∆V
REF
/
∆V
Z
vs. Temperature
0
Cathode Current (nA)
70
60
50
40
30
20
10
0
-50
Ratio (µV/V)
V
Z
= 5V
V
REF
= 0V
(Off-state)
-100
-200
-300
-400
-500
-600
I
Z
= 10mA
dV
Z
= V
REF
to 16V
-25
0
25
50
75
100
125
-50
-25
0
25
50
75
100
125
Junction Temperature (°C)
Junction Temperature (°C)
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