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. Low Voltage Operation: 1.24V Reference Initial Voltage Reference Accuracy 1% Adjustable Output Voltage From VREF to 20V Typical Output Dynamic Impedance Less Than 250mΩ Sink Current Capability 80µA To 20mA Direct Alternative To TLV431 IMPORTANT: For the most current data, consult MICROSEMI’s website: http://www.microsemi.com APPLICATIONS Low Voltage Adjustable Power Supplies Instrumentation Computers 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