LM432BA3

CYStech Electronics Corp. Adjustable shunt regulator Spec. No. : C504N3 Issued Date : 2003.03.21 Revised Date : 2005.10.07 Page No. : 1/9 LM432XA3/N3 Description The LM432 is a three terminal adjustable shunt regulator with thermal stability guaranteed over temperature. The output voltage can be adjusted to any value from 1.24V(VREF) to 20V with two external resistors. The LM432 has a typical dynamic output impedance of 0.05Ω. Active output circuitry provides a very sharp turn on characteristic, making the LM432 an excellent replacement for zener diodes. The LM432 shunt regulator is available with four voltage tolerances(0.25%,0.5%,1% and 2%), and two package options(TO-92 and SOT-23). This allows the designer the opportunity to select the optimum combination of cost and performance for their application. Features ◆Low voltage operation(down to 1.24V) ◆Wide operating current range 80μA to 100mA ◆Low dynamic output impedance 0.05Ω typ. ◆Trimmed bandgap design ±0.25% ◆Upgrade for LM431 ◆Available in TO-92 and SOT-23 packages Applications ◆Linear Regulators ◆Adjustable Supplies ◆Switching Power Supplies ◆Battery Operated Computers ◆Instrumentation ◆Computer Disk Drives Typical Application Circuit(Note 1,2) Notes: VIN R VOUT R1 VREF PL432 LM432 R2 GND 1) Set VOUT according to the following equation: VOUT=VREF(1+R1/R2)+IREFR1 2) Choose the value for R as follows: ˙The maximum limit for R should be such that the cathode current, Iz, is greater than the minimum operating current(80μA) at VIN(MIN). ˙The minimum limit for R should be as such that Iz does not exceed 100mA under all load conditions, and the instantaneous turn-on value for Iz does not exceed 150mA. Both of the following conditions must be met: Rmin≥VIN(max)/150mA(to limit instantaneous turn-on Iz) Rmin≥ VIN(max)-VOUT (to limit Iz under IOUT(min)+100mA normal operating conditions) LM432XA3/N3 CYStek Product Specification CYStech Electronics Corp. Absolute Maximum Ratings Parameter Cathode Voltage Continuous Cathode Current Reference Input Current Power Dissipation at TA=25℃ SOT-23 TO-92 Thermal Resistance SOT-23 TO-92 Operating Ambient Temperature Range Operating Junction Temperature Range Storage Temperature Range Lead Temperature(Soldering) 10 seconds ESD Rating(Human Body Model) Symbol Vz IZ IREF PD Maximum 20 100 3 0. 37 0.95 336 132 0 to +70 0 to +150 -65 to +150 300 2 Spec. No. : C504N3 Issued Date : 2003.03.21 Revised Date : 2005.10.07 Page No. : 2/9 Units V mA mA W ΘJA TA TJ Tstg T LEAD V ESD ℃/W ℃ ℃ ℃ ℃ kV Electrical Characteristics Unless otherwise specified, TA=25℃. Values in bold apply over full operating ambient temperature range. LM432D Parameter Reference Voltage VREF Temperature Deviation Ratio of Change in VREF to change in VZ Reference Input Current IREF Temperature Deviation Off-state Cathode Current Dynamic Output Impedance Minimum Operating Current Symbol Condition VREF VZ=VREF,IZ=10mA(Note 1) VDEV VZ=VREF,IZ=10mA(Note 1) ΔVREF IZ=10mA, ΔVZ=16V to VREF ΔVZ IREF R1=10kΩ,R2=∞, IZ=10mA(Note2) IREF(DEV) R1=10kΩ,R2=∞, IZ=10mA(Note 2) IZ(OFF) VREF=0V,VZ=6V(Note 3) VREF=0V,VZ=16V(Note 3) f