Datasheet

UNISONIC TECHNOLOGIES CO., LTD
ULVH431B
Preliminary
CMOS IC
LOW-VOLTAGE ADJUSTABLE
PRECISION SHUNT
REGULATOR

DESCRIPTION
The UTC ULVH431B is a low-voltage 3-terminal programmable
shunt regulator with guaranteed thermal stability over full applicable
industrial and commercial temperature ranges.
The output voltage of UTC ULVH431B can be set to any value
between VREF (1.24V) and the corresponding maximum cathode
voltage (18V) with two external resistors. The device operates from
a lower voltage (1.24V) than the widely used TL431 and TL1431
shunt-regulator references.
The UTC ULVH431B is an ideal voltage reference in isolated
feedback circuits for 3-V to 3.3-V switching-mode power supplies
when it is used with an opto-coupler. It has a typical output
impedance of 0.25Ω. Active output circuitry supplies a very sharp
turn-on characteristic, which makes the UTC ULVH431B very good
substitute for low-voltage Zener diode in many applications such as
adjustable power supplies and on-board regulation.

FEATURES
* Adjustable output voltage, VO=VREF to 18 V
* Low-Voltage operation: VREF= 1.24 V
* Wide operating cathode current range: 55µA to 50mA
* Reference voltage tolerances at 25°C
* 0.25-Ω typical output impedance
* -40°C ~ 125°C specifications

ORDERING INFORMATION
Ordering Number
Package
ULVH431BG-AE2-R
ULVH431BG-AE3-R
SOT-23-3
SOT-23
www.unisonic.com.tw
Copyright © 2016 Unisonic Technologies Co., Ltd
Pin Assignment
1
2
3
K
R
A
K
R
A
Packing
Tape Reel
Tape Reel
1 of 6
QW-R103-115 .a
ULVH431B

Preliminary
CMOS IC
MARKING
H431B

PIN CONFIGURATION

PIN DESCRIPTION
PIN NO.
1
2
3

PIN NAME
CATHODE
REF
ANODE
DESCRIPTION
Cathode voltage
Reference voltage
Anode voltage
BLOCK DIAGRAM
CATHODE
+
REF
VREF=1.24V
ANODE
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
2 of 6
QW-R103-115 .a
ULVH431B

Preliminary
CMOS IC
ABSOLUTE MAXIMUM RATING
PARAMETER
SYMBOL
RATINGS
UNIT
Cathode Voltage (Note 1)
VKA
20
V
Cathode Current Range
IK
-25 ~ 50
mA
Reference Current Range
Iref
-0.05 ~ 3
mA
Operating Virtual Junction Temperature
TJ
150
°C
Storage Temperature Range
TSTG
-65 ~ +150
°C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.

THERMAL RESISTANCES CHARACTERISTICS
PARAMETER
SYMBOL
RATINGS
Package Thermal Impedance (Note 2)
θJA
206
Note: Voltage values are with respect to the anode terminal, unless otherwise noted.

UNIT
°C/W
RECOMMENDED OPERATING CONDITIONS
PARAMETER
Cathode Voltage
Cathode Current (Continuous)
Operating Free-Air Temperature Range
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
SYMBOL
VKA
IK
TA
MIN
VREF
0.1
-40
TYP
MAX
18
50
125
UNIT
V
mA
°C
3 of 6
QW-R103-115 .a
ULVH431B

Preliminary
CMOS IC
ELECTRICAL CHARACTERISTICS (TA=25°C free-air temperature, unless otherwise specified)
PARAMETER
Reference Voltage
VREF Deviation Over Full
Temperature Range (Note 2)
Ratio of VREF Change to
Cathode Voltage Change
Reference Terminal Current
Iref Deviation Over Full
Temperature Range (Note 2)
Minimum Cathode Current for
Regulation
Off-State Cathode Current
SYMBOL
VREF
VREF(dev)
∆VREF
∆VKA
Iref
Iref(dev)
IK(min)
TEST CONDITIONS
TA=25°C
VKA=VREF,
TA=Full Range
IK=10mA
(Note 1 and Figure 1)
VKA=VREF, IK=10mA
(Note 1 and Figure 1)
IK=10mA (see Figure 2), VKA=VREF~18V
IK=10mA, R1=10kΩ, R2=OPEN
(see Figure 2)
IK=10mA, R1=10kΩ, R2=Open
(see Note 1 and Figure 2)
VKA=VREF (see Figure 1)
MIN
1.234
TYP
1.24
MAX
1.246
UNIT
V
1.265
V
11
31
mV
-1.5
-2.7
mV/V
0.1
0.5
µA
0.15
0.5
µA
60
100
µA
1.221
IK(off)
VREF=0, VKA=18V (see Figure 3)
0.02
0.1
µA
VKA=VREF, f≤1kHz, IK=0.1mA~50mA
0.25
0.4
Ω
Dynamic Impedance (Note 3)
|zKA|
(see Figure 1)
Notes: 1. Full temperature ranges are: -40°C~125°C for ULVH431B.
2. The deviation parameters VREF(dev) and Iref(dev) are defined as the differences between the maximum and
minimum values obtained over the rated temperature range. The average full-range temperature
VREF( dev )
(
) × 106
ppm
VREF (TA = 25°C)
coefficient of the reference input voltage, αVREF, is defined as: αVREF (
)=
∆TA
°C
where ∆TA is the rated operating free-air temperature range of the device.
αVREF can be positive or negative, depending on whether minimum VREF or maximum VREF, respectively,
occurs at the lower temperature.
∆VKA
3. The dynamic impedance is defined as: zka =
∆IK
When the device is operating with two external resistors (see Figure 2), the total dynamic impedance of
R1
∆V
the circuit is defined as: zka =
≈zka × (1+
)
R2
∆I
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
4 of 6
QW-R103-115 .a
ULVH431B

Preliminary
CMOS IC
EQUIVALENT SCHEMATIC
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
5 of 6
QW-R103-115 .a
ULVH431B

Preliminary
CMOS IC
PARAMETER MEASUREMENT INFORMATION
VO
VIN
IK(off)
Figure 3. Test Circuit for IK(off)
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
6 of 6
QW-R103-115 .a
Similar pages