Microsemi LX432 Low voltage adjustable precision shunt regulator Datasheet

LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
KEY FEATURES
DESCRIPTION
Low voltage operation enables the
LX432 to be used in the feedback loop of
isolated low voltage power supplies. The
minimum output voltage is determined by
the LX432 output voltage plus the forward
voltage drop of the opto-coupler LED
(typically 1.24 + 1.4 = 2.64V minimum).
See figure 12.
The LX432 is offered in 3 lead SOT-23
or TO-92 packages, and is a drop-in
replacement for the TLV431 and SC431L
devices.
WWW . Microsemi .C OM
The LX432 series are low-voltage
precision adjustable shunt regulators with
a reference voltage of 1.24V. The output
voltage may be set to any value between
1.24V and 20V by two external resistors.
These devices offer low output
impedance for improved load regulation –
typical output impedance is 200mΩ. The
LX432 series operates with an operating
current as low as 80µA, making these
devices suitable for portable and
micropower applications.
ƒ Low Voltage Operation:
1.24V Reference
ƒ Initial Voltage Reference
Accuracy 1%
ƒ Adjustable Output Voltage
From VREF to 20V
ƒ Typical Output Dynamic
Impedance Less Than
250mΩ
ƒ Sink Current Capability
80µA To 20mA
ƒ Direct Alternative To
TLV431
IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com
APPLICATIONS
ƒ Low Voltage Adjustable
Power Supplies
ƒ Instrumentation
ƒ Computers
ƒ Portable Equipment
PRODUCT HIGHLIGHT
V IN
V KA
R1
Cathode
Reference
LX432
Anode
R2
GND
LX 4 3 2
PACKAGE ORDER INFO
TA (°C)
SC
Package
Marking
0 to 70
-40 to 85
432C
432I
SC
Plastic SOT-23
3-Pin
LP
Plastic TO-92
3-Pin
RoHS Compliant / Pb-free RoHS Compliant / Pb-free
Transition DC: 0503
Transition DC: 0509
LX432CSC
LX432ISC
LX432CLP
LX432ILP
Note: Available in Tape & Reel. Append the letters “TR” to the part number. (i.e. LX432CSC-TR)
TO-92 (LP) package also available in ammo-pack.
Copyright © 2000
Rev. 1.3, 2005-02-24
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
PACKAGE PIN OUT
(NOTE 1)
Cathode to Anode Voltage (VKA)..................................................................-0.3V to +20V
Reference Input Current (IREF) .....................................................................-50µA to 10µA
Continuous Cathode Current (IK)............................................................... -25mA to 25mA
Operating Junction Temperature................................................................................ 150°C
Storage Temperature....................................................................................-65ºC to 150°C
RoHS / Pb-free Peak Package Solder Reflow Temperature
(40 second maximum exposure) ....................................................................260°C (+0,-5)
REF
1
3
CATHODE
ANO DE
2
SC PACKAGE – 3-PIN
Note 1: Exceeding these ratings could cause damage to the device. All voltages are with respect to
Ground. Currents are positive into, negative out of specified terminal.
WWW . Microsemi .C OM
ABSOLUTE MAXIMUM RATINGS
3. C ATHODE
2. A NODE
THERMAL DATA
SC
3-Pin Plastic Package
LP PACKAGE – 3-PIN
Thermal Resistance – Junction to Ambient, θJA
LP
1. R EF
(PC Mounted)
220°C/W
(Non-PC Mounted) 410°C/W
RoHS / Pb-free 100% Matte Tin Lead Finish
(All Views Top View)
3-Pin Plastic Package
156°C/W
Thermal Resistance – Junction to Ambient, θJA
Junction Temperature Calculation: TJ = TA + (PD x θJA).
The θJA numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.
BLOCK DIAGRAM
Cathode (K)
+
Ref(R)
PACKAGE DATA
V REF
Anode(A)
Figure 1 – Simplified Block Diagram
Copyright © 2000
Rev. 1.3, 2005-02-24
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LX432
®
TM
Low Voltage Adjustable Precision Shunt Regulator
P RODUCTION D ATA S HEET
Unless otherwise specified, the following specifications apply over the operating ambient temperature for the LX432C with 0°C
70°C and the LX432I with -40°C < TA < 85°C except where otherwise noted.
Parameter
Symbol
Reference Voltage
Reference Voltage Drift (note 2)
VREF
∆VREF
Ratio of VREF Change In Cathode
Voltage Change (note 3)
∆VREF
Reference Terminal Current
Reference Current Drift (note 2)
Minimum Cathode Current For
Regulation
Dynamic Impedance
Off-State Cathode Current
∆VKA
IREF
∆IREF
IK(MIN)
ZKA
IOFF
Test Conditions
IK = 10mA, VKA = VREF, TA = 25°C
IK = 10mA, VKA = VREF, 0°C < TA < 70°C
IK = 10mA, VKA = VREF, -40°C < TA < 85°C
Min
1.228
IK = 10ma, VKA = VREF to 16V, TA = 25°C
IK = 10mA, VKA = VREF, TA=25°C, R1=10kΩ,
R2=Open
IK = 10mA, VKA = VREF, 0°C < TA < 70°C
IK = 10mA, VKA = VREF, -40°C < TA < 85°C
VKA = VREF, TA = 25°C
IK = 0.1mA to 15mA, VKA = VREF, TA = 25°C
VKA = 16V, TA = 25°C
≤
TA ≤
LX432
Typ
1.24
3
4
Max
1.252
12
20
-1
-2.7
mV/V
0.1
0.5
µA
0.05
0.1
0.3
0.4
µA
µA
55
80
µA
0.2
0.004
0.4
Ω
µA
Units
V
mV
mV
WWW . Microsemi .C OM
ELECTRICAL CHARACTERISTICS
Note 2: These parameters are guaranteed by design.
∆VREF
Note 3:
Ratio of change in reference input voltage to the change in cathode voltage
∆VKA
ELECTRICALS
Copyright © 2000
Rev. 1.3, 2005-02-24
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
WWW . Microsemi .C OM
CHARACTERISTIC CURVES
STABILITY BOUNDARY CONDITION†
30
Unstable
25
IK Cathode Current (mA)
VKA = 2V
20
Stable
15
VKA = 3V
10
5
0
0.001
VKA = VREF
*
0.010
0.100
1.000
10.000
CL- Load Capacitance (uF)
Figure 2 – Stability
* Unstable below 700µA as indicated
† The unstable areas indicate loading conditions that may cause the device to oscillate.
STABILITY
Copyright © 2000
Rev. 1.3, 2005-02-24
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
1.242
WWW . Microsemi .C OM
CHARACTERISTIC CURVES
0.2
0.18
1.241
IREF: Reference Current(µA)
V REF: Reference Voltage (V)
0.16
1.24
1.239
1.238
1.237
1.236
0.14
0.12
0.1
0.08
0.06
0.04
0.02
1.235
-50
0
25
50
75
100
0
-50
125
TJ: Junction Temperature (°C)
0
25
50
75
100
125
T J: Junction Temperature (°C)
Figure 3 – Reference Voltage vs. Junction Temperature
Figure 4 – Reference Current vs. Junction Temperature
900
-1.2
800
-1
∆V REF / ∆V KA (mV/V)
600
500
400
300
200
-0.8
-0.6
CHARACTERISTICS
IK: Cathode Current (µA)
700
-0.4
100
-0.2
0
1.5
1.25
1
0.75
0.5
0.25
0
-0.3
-0.5
-0.8
-1
-100
Cathode Voltage (V)
0
25
50
75
100
125
TJ: Junction Temperature (°C)
Figure 5 – Cathode Current vs. Cathode Voltage
Copyright © 2000
Rev. 1.3, 2005-02-24
0
-50
Figure 6 – ∆VREF / ∆VKA vs. Junction Temperature
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
0.8
WWW . Microsemi .C OM
CHARACTERISTIC CURVES
120
Minimum Cathode Current (µA)
Dynamic Impedance (ohm)
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
-50
0
25
50
75
100
80
60
40
20
0
-50
125
0
25
50
75
100
125
T J: Junction Temperature (°C)
T J: Junction Temperature (°C)
Figure 7 – Dynamic Impedance vs. Junction Temperature
Figure 8 – Minimum Cathode Current for Regulation vs.
Junction Temperature
0.07
350
0.06
300
Noise Voltage (nV/sqrt(Hz))
Off-State Current (µA)
100
0.05
0.04
0.03
0.02
0.01
150
100
50
0
0
25
70
85
125
T J: Junction Temperature (°C)
10
100
1K
10K
100K
Frequency (Hz)
Figure 9 – Off-State Current vs. Junction Temperature
Copyright © 2000
Rev. 1.3, 2005-02-24
200
Figure 10 – Equivalent Input Noise Voltage vs. Frequency
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
CHARACTERISTICS
0
-50
250
LX432
®
TM
Low Voltage Adjustable Precision Shunt Regulator
P RODUCTION D ATA S HEET
WWW . Microsemi .C OM
PARAMETER MEASUREMENT INFORMATION
V KA
Input
IK
V REF
Figure 11 – Test Circuit For VKA = VREF
V KA
Input
I OFF
IK
R1
R2
I REF
V REF
Figure 12 – Test Circuit For VKA > VREF
Figure 13 – Test Circuit For IOFF
R1 ⎞
⎟ + IREF × R1
R2 ⎠
MEASUREMENT
⎛
⎝
VO = VKA = VREF × ⎜ 1 +
Copyright © 2000
Rev. 1.3, 2005-02-24
V KA
Input
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
V IN
110 / 220V AC
_
C ontroller
U C 384x / LX155x
V O UT
3.3V
+
+
+
WWW . Microsemi .C OM
TYPICAL APPLICATION
DRV V
CC
I SEN SE
GND
V FB
+
+
LX 432
Figure 12 – LX432 In A Power Supply Isolated Feedback Application
12V
3.3V
470µF
0.1µF
0.1µF
500 Ω
140 Ω
LX432
2.7V
120 Ω
1000µF
APPLICATIONS
(e.g. Intel i740 ® chipset)
0.1µF
Figure 13 – LX432 in a 3.3V to 2.7V Low Dropout Regulator Application
Copyright © 2000
Rev. 1.3, 2005-02-24
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
LX432
Low Voltage Adjustable Precision Shunt Regulator
®
TM
P RODUCTION D ATA S HEET
3-Pin Plastic SOT-23
SC
Dim
D
A
B
C
D
E
F
G
H
I
J
E
H
F
G
MILLIMETERS
MIN
MAX
0.89
1.12
0.37
0.51
0.085
0.18
2.80
3.04
1.20
1.40
0.89
1.09
1.78
2.05
2.10
2.64
0.35
0.55
0.013
0.10
INCHES
MIN
MAX
0.035
0.044
0.015
0.020
0.003
0.007
0.110
0.120
0.047
0.055
0.035
0.043
0.070
0.080
0.083
0.104
0.014
0.022
0.0005 0.0039
WWW . Microsemi .C OM
PACKAGE DIMENSIONS
Note:
A
B
LP
J
C
I
3-Pin Plastic TO-92
Dim
A
J
D
x
C
V
x
N
K
N
F
MILLIMETERS
MIN
MAX
4.45
5.20
4.32
5.33
3.18
4.19
0.41
0.55
0.41
0.48
1.15
1.39
2.42
2.66
0.39
0.50
12.70
2.05
2.66
3.43
-
INCHES
MIN
MAX
0.175
0.205
0.170
0.210
0.125
0.165
0.016
0.022
0.016
0.019
0.045
0.055
0.095
0.105
0.015
0.020
0.500
0.080
0.105
0.135
-
MECHANICALS
A
B
C
D
F
G
H
J
K
N
V
SECT x-x
B
Note:
G
1. Dimensions do not include mold flash or
protrusions;
these
shall
not
exceed
0.155mm(.006”) on any side. Lead dimension
shall not include solder coverage.
H
Copyright © 2000
Rev. 1.3, 2005-02-24
1. Dimensions do not include mold flash or
protrusions;
these
shall
not
exceed
0.155mm(.006”) on any side. Lead dimension
shall not include solder coverage.
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9
LX432
TM
®
Low Voltage Adjustable Precision Shunt Regulator
P RODUCTION D ATA S HEET
WWW . Microsemi .C OM
NOTES
NOTES
PRODUCTION DATA – Information contained in this document is proprietary to
Microsemi and is current as of publication date. This document may not be modified in
any way without the express written consent of Microsemi. Product processing does not
necessarily include testing of all parameters. Microsemi reserves the right to change the
configuration and performance of the product and to discontinue product at any time.
Copyright © 2000
Rev. 1.3, 2005-02-24
Microsemi
Integrated Products Division
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 10
Similar pages