Issue 8 - April 2007 1 www.zetex.com
© Zetex Semiconductors plc 2007
ZTL431, ZTL432
Cost effective adjustable precision shunt regulator
Description
The ZTL431 and ZTL432 are three terminal
adjustable shunt regulators offering excellent
temperature stability and output current
handling capability up to 100mA. The output
voltage may be set to any chosen voltage
between 2.5 and 20 volts by selection of two
external divider resistors.
The devices can be used as a replacement for
zener diodes in many applications requiring an
improvement in zener performance.
Features
• Temperature range ................ -40 to 125°C
• Reference voltage tolerance at 25°C
• 0.5% ..................................... B grade
• 1% ......................................... A grade
• Low output noise
• 0.2 typical output impedance
• Sink current capability ...... 1mA to 100mA
• Adjustable output voltage...... VREF to 20V
Pin connections
The ZTL432 has the same electrical specifications
as the ZTL431 but has a different pin out in
SOT23 (F-suffix) and SOT23F (FF-suffix).
Both variants are available in 2 grades with
initial tolerances of 1% and 0.5% for the A and
B grades respectively.
These are functionally equivalent to the TL431/
TL432 except for maximum operation voltage,
and have an ambient temperature range of -40
to 125°C as standard.
Applications
• Opto-coupler linearization
• Linear regulators
• Improved zener
• Variable reference
1 Cathode
ZTL431_F SOT23
ZTL431_FF SOT23F
(top view)
ZTL432_F SOT23
ZTL432_FF SOT23F
(top view)
Ref
Ref
Cathode
2
3 Anode Anode
1
2
3
1
2
3
6
5
4
ZTL431_H6 SC70-6
(top view)
Cathode
*
REF
Anode
*
NC
Preview
ZTL431, ZTL432
Issue 8 - April 2007 2 www.zetex.com
© Zetex Semiconductors plc 2007
Ordering information
Absolute maximum ratings
Cathode voltage (VKA) .............................................................. 20V
Continuous cathode current (IKA) ........................................ 150mA
Reference input current range (IREF)..................... -50 µA to 10mA
Operating junction temperature ................................. -40 to 150°C
Storage temperature ................................................... -55 to 150°C
Operation above the absolute maximum rating may cause device failure. Operation at the
absolute maximum ratings, for extended periods, may reduce device reliability.
Unless otherwise stated voltages specified are relative to the ANODE pin.
Package thermal data
Tol. Order code Pack
Part mark
Status*Reel Size
Tape width
(mm)
Quantity
per reel
1%
ZTL431ACSTZ TO92 ZTL431A Active Concertina N/A 1500
ZTL431AE5TA SOT23-5 31A Preview*7”, 180mm 8 3000
ZTL431AFFTA SOT23F 31A Active 7”, 180mm 8 3000
ZTL431AFTA SOT23 31A Active 7”, 180mm 8 3000
ZTL431AH6TA SC70-6 31A Preview*7”, 180mm 8 3000
ZTL431AZTA SOT89 31A Preview*7”, 180mm 12 1000
ZTL432AFFTA SOT23F 32A Active 7”, 180mm 8 3000
ZTL432AFTA SOT23 32A Active 7”, 180mm 8 3000
0.5%
ZTL431BCSTZ TO92 ZTL431B Preview*Concertina N/A 1500
ZTL431BE5TA SOT23-5 31B Preview*7”, 180mm 8 3000
ZTL431BFFTA SOT23F 31B Preview*7”, 180mm 8 3000
ZTL431BFTA SOT23 31B Active 7”, 180mm 8 3000
ZTL431BH6TA SC70-6 31B Preview*7”, 180mm 8 3000
ZTL431BZTA SOT89 31B Preview*7”, 180mm 12 1000
ZTL432BFFTA SOT23F 32B Active 7”, 180mm 8 3000
ZTL432BFTA SOT23 32B Active 7”, 180mm 8 3000
NOTES:
* For availability of pre-production status devices contact your local Zetex representative
Package ⍜JA PDIS
TA =25°C, TJ = 150°C
TO92 160°C/W 780mW
SOT23 380°C/W 330mW
SOT23F 138°C/W 900mW
SOT23-5 250°C/W 500mW
SOT89 125°C/W 1000mW
ZTL431, ZTL432
Issue 8 - April 2007 3 www.zetex.com
© Zetex Semiconductors plc 2007
Recommended operating conditions
Electrical characteristics
Electrical characteristics over recommended operating conditions, T
A
= 25°C, unless otherwise stated.
Min Max Units
VKA Cathode voltage Vref 20 V
IKA Cathode current 1 100 mA
TA Operating ambient temperature range -40 125 °C
Symbol
Parameter Conditions Min. Typ. Max. Units
VREF Reference voltage VKA = VREF
IKA = 10mA
ZTL43_A 2.475 2.5 2.525 V
ZTL43_B 2.487 2.5 2.513
VDEV Deviation of reference
voltage over full
temperature range
VKA = VREF
IKA = 10 mA
TA = 0 to 70° 6 16
mV
TA = -40 to 85°C 14 34
TA = -40 to 125°C 14 34
ΔVREF
ΔVKA
Ratio of change in
reference voltage
to the change in
cathode voltage
IKA = 10mA
VKA = VREF to 10 -1.4 -2.7 mV/V
VKA = 10V to 20V -1.0 -2.0
IREF Reference input
current
IKA = 10mA, R1 = 10k⍀
R2 = OC
24µA
ΔIREF IREF deviation over full
temperature range
IKA = 10mA
R1 = 10k⍀
R2 = OC
TA = 0 to 70°C 0.8 1.2
µA
TA = -40 to 85°C 0.8 2.5
TA = -40 to 125°C 0.8 2.5
I
KA(MIN)
Minimum cathode
current for regulation
VKA = VREF 0.4 0.6 mA
IKA(OFF) Off state current VKA = 20V, VREF = 0V 0.1 0.5 µA
RZDynamic output
impedance
VKA = VREF
, f = 0Hz 0.2 0.5 ⍀
ZTL431, ZTL432
Issue 8 - April 2007 6 www.zetex.com
© Zetex Semiconductors plc 2007
Application cicuits
VON~ 2V
VOFF = V+
VTH = 2.5V
Output
V+
Input
R1
R2
VOUT
VOUT
V+
VREF
VREF
R1
R2
VOUT
VOUT
V+
VREF
VREF
R1
R2
VOUT
VOUT
V+
VREF
VREF
VOUT(MIN) = VREF + VREG
In Out
Common
ZSR***
0.01F
30⍀
R1
R2
VREF
V+
VOUT
VOUT VREF
R1
R1
R2b
R2a
VREF
VREF
VREF
VREF
V+
Output
Shunt regulator
Output control of a three
terminal fixed regulator
Single supply comparator
with temperature
compensated threshold
Higher current shunt
regulator
Series regulator
Over voltage / under voltage
protection circuit
ZTL431, ZTL432
Issue 8 - April 2007 7 www.zetex.com
© Zetex Semiconductors plc 2007
DC test circuits
Notes
Deviation of reference input voltage, Vdev, is
defined as the maximum variation of the
reference input voltage over the full
temperature range.
The average temperature coefficient of the
reference input voltage, Vref is defined as:
The dynamic output impedance, Rz, is
defined as:
When the device is programmed with two
external resistors, R1 and R2, (fig 2), the
dynamic output impedance of the overall
circuit, R'z, is defined as:
Stability boundary
The ZTL431 and ZTL432 are stable with a
range of capacitive loads. A zone of instability
exists as demonstrated in the typical
characteristic graph on page 5. The graph
shows typical conditions. To ensure reliable
stability a capacitor of 4.7nF or greater is
recommended between anode and cathode.
Figure 1 Test circuit for
V
KA
= V
REF
Figure 2 Test circuit for
V
KA
> V
REF
Figure 3 Test circuit for
off state current
IKA IKA IKA(OFF)
ILIL
VKA VKA VKA
VREF VREF
IREF IREF
VREF ppm°C()
VDEV 1 000 000,,×
VREF T1 T2–()
-------------------------------------------------=
Rz
ΔVz
ΔIz
----------=
R'zRz1R1
R2
-------+
⎝⎠
⎛⎞
=
ZTL431, ZTL432
Issue 8 - April 2007 8 www.zetex.com
© Zetex Semiconductors plc 2007
Pin connections - preview status devices
ZTL431_E5 SOT235
(top view)
ZTL431_Z SOT89
(top view)
N/C
*
Cathode
Anode
Anode
Cathode
Anode
Ref Ref
1
2
3
5
4
Preview
Preview
* Pin 2 should be left floating or connected to pin 5
ZTL431_C TO92
(underside view)
Vz
Gnd
Vref
1
2
3
ZTL431, ZTL432
Issue 8 - April 2007 9 www.zetex.com
© Zetex Semiconductors plc 2007
Packaging details - SOT23
Packaging details - SOT23-5
Note: Controlling dimensions are in millimeters.
Approximate dimensions are provided in inches
Note: Controlling dimensions are in millimeters.
Approximate dimensions are provided in inches
E
e
L
e1
D
A
c
E1
L1
A1
b
3 leads
Dim. Millimeters Inches Dim. Millimeters Inches
Min. Max. Min. Max. Min. Max. Max. Max.
A - 1.12 - 0.044 e1 1.90 NOM 0.075 NOM
A1 0.01 0.10
0.0004
0.004 E 2.10 2.64 0.083 0.104
b 0.30 0.50 0.012 0.020 E1 1.20 1.40 0.047 0.055
C0.085
0.120
0.003 0.008 L 0.25 0.62 0.018 0.024
D 2.80 3.04
0.110
0.120 L1 0.45 0.62 0.018 0.024
e 0.95 NOM 0.0375 NOM - - - - -
Dim. Millimeters Inches
Min. Max. Min. Max.
A 0.90 1.45 0.0354 0.0570
A1 0.00 0.15 0.00 0.0059
A2 0.90 1.30 0.0354 0.0511
b 0.20 0.50 0.0078 0.0196
C 0.09 0.26 0.0035 0.0102
D 2.70 3.10 0.1062 0.1220
E 2.20 3.20 0.0866 0.1181
E1 1.30 1.80 0.0511 0.0708
e 0.95 REF 0.0374 REF
e1 1.90 REF 0.0748 REF
L 0.10 0.60 0.0039 0.0236
a° 0° 30° 0° 30°
ZTL431, ZTL432
Issue 8 - April 2007 10 www.zetex.com
© Zetex Semiconductors plc 2007
Package details - SOT89
Package details - TO92
Note: Controlling dimensions are in millimeters.
Approximate dimensions are provided in inches
Note: Controlling dimensions are in millimeters.
Approximate dimensions are provided in inches
D1
DA
C
B1
L
E
HE1
Be
e1
C
Dim. Millimeters Inches Dim. Millimeters Inches
Min. Max. Min. Max. Min. Max. Min Max.
A 1.40 1.60 0.550 0.630 E1 2.13 2.29 0.084 0.090
B 0.44 0.56 0.017 0.022 e 1.50 BSC 0.059 BSC
B1 0.36 0.48 0.014 0.019 e1 3.00 BSC 0.118 BSC
C 0.35 0.44 0.014 0.019 H 3.94 4.25 0.155 0.167
D 4.40 4.60 0.173 0.181 L 0.89 1.20 0.155 0.167
E2.292.600.0900.102 ----
Dim. Millimeters Inches
Min. Max. Min. Max.
A 4.32 4.95 0.170 0.195
b 0.36 0.51 0.014 0.020
C 2.50 3.50 0.099 0.138
E 3.30 3.94 0.130 0.155
e 4.88 5.88 0.192 0.232
e1 2.44 2.94 0.096 0.116
L 12.70 15.49 0.500 0.610
R 2.16 2.41 0.085 0.095
S1 1.14 1.52 0.045 0.060
W 0.41 0.56 0.016 0.022
D 4.45 4.95 0.175 0.195
*° 4° 6° 4° 6°
ZTL431, ZTL432
Issue 8 - April 2007 11 www.zetex.com
© Zetex Semiconductors plc 2007
Package details - SC70-6
Package details SOT23F
Note: Controlling dimensions are in millimeters.
Approximate dimensions are provided in inches
Note: Controlling dimensions are in millimeters.
Approximate dimensions are provided in inches
␣
D
L1
c
A1
b
R
bb
E1 E
e1
e
L
A
E2
Dim. Millimeters Inches Dim
.
Millimeters Inches
Min. Max. Min. Max. Min. Max. Max. Max.
A
0.80 1.10 0.0315 0.0433 E 2.10 BSC 0.0826 BSC
A1
- 0.10 - 0.0039 E1 1.25 1.35 0.0492 0.0531
A2
0.80 1.00 0.0315 0.0394 e 0.65 BSC 0.0255 BSC
b
0.15 0.30 0.006 0.0118 e1 1.30 BSC 0.0511 BSC
C
0.08 0.25 0.0031 0.0098 L 0.26 0.46 0.0102 0.0181
D 2.00 BSC 0.0787 BSC ␣0° 8° 0° 8°
Dim. Millimeters Inches Dim. Millimeters Inches
Min. Max. Min. Max. Min. Max. Max. Max.
A 0.80 1.00 0.031 0.0394 E 2.30 2.50 0.0906 0.0984
A1 - 0.10 0.00 0.0043 E1 1.50 1.70 0.0590 0.0669
A2 0.06 0.16
0.0024
0.0006 E2 1.10 1.26 0.0433 0.0496
b0.390.41
0.0153
0.0161 L 0.48 0.68 0.0189 0.0268
c0.110.20
0.0043
0.0079 L1 0.39 0.41 0.0153 0.0161
D2.803.00
0.1102
0.1181 R 0.05 0.15 0.0019 0.0059
e 0.95 ref 0.0374 ref O 0° 12° 0° 12°
e1 1.90 ref 0.7480 ref - - - - -
ZTL431, ZTL432
Issue 8 - April 2007 12 www.zetex.com
© Zetex Semiconductors plc 2007
Zetex sales offices
Europe
Zetex GmbH
Kustermann-park
Balanstraße 59
D-81541 München
Germany
Telefon: (49) 89 45 49 49 0
Fax: (49) 89 45 49 49 49
europe.sales@zetex.com
Americas
Zetex Inc
700 Veterans Memorial Highway
Hauppauge, NY 11788
USA
Telephone: (1) 631 360 2222
Fax: (1) 631 360 8222
usa.sales@zetex.com
Asia Pacific
Zetex (Asia Ltd)
3701-04 Metroplaza Tower 1
Hing Fong Road, Kwai Fong
Hong Kong
Telephone: (852) 26100 611
Fax: (852) 24250 494
asia.sales@zetex.com
Corporate Headquarters
Zetex Semiconductors plc
Zetex Technology Park, Chadderton
Oldham, OL9 9LL
United Kingdom
Telephone: (44) 161 622 4444
Fax: (44) 161 622 4446
hq@zetex.com
© 2007 Published by Zetex Semiconductors plc
Definitions
Product change
Zetex Semiconductors reserves the right to alter, without notice, specifications, design, price or conditions of supply of any product or
service. Customers are solely responsible for obtaining the latest relevant information before placing orders.
Applications disclaimer
The circuits in this design/application note are offered as design ideas. It is the responsibility of the user to ensure that the circuit is fit for
the user’s application and meets with the user’s requirements. No representation or warranty is given and no liability whatsoever is
assumed by Zetex with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights
arising from such use or otherwise. Zetex does not assume any legal responsibility or will not be held legally liable (whether in contract,
tort (including negligence), breach of statutory duty, restriction or otherwise) for any damages, loss of profit, business, contract,
opportunity or consequential loss in the use of these circuit applications, under any circumstances.
Life support
Zetex products are specifically not authorized for use as critical components in life support devices or systems without the express written
approval of the Chief Executive Officer of Zetex Semiconductors plc. As used herein:
A. Life support devices or systems are devices or systems which:
1. are intended to implant into the body
or
2. support or sustain life and whose failure to perform when properly used in accordance with instructions for use provided in the
labelling can be reasonably expected to result in significant injury to the user.
B. A critical component is any component in a life support device or system whose failure to perform can be reasonably expected to
cause the failure of the life support device or to affect its safety or effectiveness.
Reproduction
The product specifications contained in this publication are issued to provide outline information only which (unless agreed by the
company in writing) may not be used, applied or reproduced for any purpose or form part of any order or contract or be regarded as a
representation relating to the products or services concerned.
Terms and Conditions
All products are sold subjects to Zetex’ terms and conditions of sale, and this disclaimer (save in the event of a conflict between the two
when the terms of the contract shall prevail) according to region, supplied at the time of order acknowledgement.
For the latest information on technology, delivery terms and conditions and prices, please contact your nearest Zetex sales office.
Quality of product
Zetex is an ISO 9001 and TS16949 certified semiconductor manufacturer.
To ensure quality of service and products we strongly advise the purchase of parts directly from Zetex Semiconductors or one of our
regionally authorized distributors. For a complete listing of authorized distributors please visit: www.zetex.com/salesnetwork
Zetex Semiconductors does not warrant or accept any liability whatsoever in respect of any parts purchased through unauthorized sales channels.
ESD (Electrostatic discharge)
Semiconductor devices are susceptible to damage by ESD. Suitable precautions should be taken when handling and transporting devices.
The possible damage to devices depends on the circumstances of the handling and transporting, and the nature of the device. The extent
of damage can vary from immediate functional or parametric malfunction to degradation of function or performance in use over time.
Devices suspected of being affected should be replaced.
Green compliance
Zetex Semiconductors is committed to environmental excellence in all aspects of its operations which includes meeting or exceeding
regulatory requirements with respect to the use of hazardous substances. Numerous successful programs have been implemented to
reduce the use of hazardous substances and/or emissions.
All Zetex components are compliant with the RoHS directive, and through this it is supporting its customers in their compliance with
WEEE and ELV directives.
Product status key:
“Preview” Future device intended for production at some point. Samples may be available
“Active” Product status recommended for new designs
“Last time buy (LTB)” Device will be discontinued and last time buy period and delivery is in effect
“Not recommended for new designs”
Device is still in production to support existing designs and production
“Obsolete” Production has been discontinued
Datasheet status key:
“Draft version” This term denotes a very early datasheet version and contains highly provisional information, which
may change in any manner without notice.
“Provisional version” This term denotes a pre-release datasheet. It provides a clear indication of anticipated performance.
However, changes to the test conditions and specifications may occur, at any time and without notice.
“Issue” This term denotes an issued datasheet containing finalized specifications. However, changes to
specifications may occur, at any time and without notice.
