TL432A

Low Voltage(1.24V) Adjustable Precision Shunt Regulator PROGRAMMABLE PRECISION REFERENCES The TL432A is a three-terminal Shunt Voltage Reference providing a highly accurace 1.24 V, 1.25V bandgap reference with 1.0 % tolerance. The TL432A thermal stability and wide operating current (100mA), makes is suitable for all variety of applications that are looking for a low cost solution with high performance. The TL432A is an ideal voltage reference in an isolated feed circuit for 3.0V to 3.3V switching mode power supplies. TO-92 (Top View) TL432/ A / C 3.Cathode 2.Anode 1.Reference SOT-23 (Front View) 2.Anode FEATURES Low Voltage Operation : 1.24 V Programmable Out Voltage to 15V ● Sink Current Capability of 1 mA to 100 mA ● Equivalent Full-Range Temperature Coefficient of 50 ppm/℃ ● Temperature Compensated for Operation over Full Rated Operating Temperature Range ● Trimmed Bandgap to 5% ● ESD Protection : 2kV ● ● 1.Reference 3.Cathode ORDERING INFORMATION Device TL432-A TL432-C TL432-ASF TL432-CSF Marking TL432-A TL432-C 432 Package TO-92 SOT-23 APPLICATION Shunt Regulator Voltage Monitoring ● Current Source and Sink Circuits ● Anolog and Digital Circuits Requiring Precision References ● Low Out Voltage (3.0V to 3.3V) Switching Power Supply Error Amplifier ● ● FUNCTION BLOCK DIAGRAM CATHODE REFERENCE + REFERENCE(R) 1.24VREF CATHODE(K) ANODE(A) ANODE Jan, 2004 - Rev 01 HTC 21 Low Voltage(1.24V) Adjustable Precision Shunt Regulator EQUIVALENT SCHEMATIC TL432/ A / C All component values are nominal RECOMMENDED OPERATING CONDITIONS CHARACTERISTIC Cathode Voltage Cathode Current SYMBOL VKA IK MIN. VREF 1 MAX. 15 100 UNIT V ㎃ DISSIPATION RATING TABLE1-FREE-AIR TEMPERATURE Package TO-92 SOT-89 SOT-23 TA=25℃ Power Rating 770㎽ 230㎽ Derating Factor Above TA=25℃ 6.2㎽/℃ 1.8㎽/℃ TA=70℃ TA=85℃ TA=125℃ Power Rating Power Rating Power Rating 491㎽ 398㎽ 149㎽ 122㎽ Jan, 2004 - Rev 01 HTC 22 Low Voltage(1.24V) Adjustable Precision Shunt Regulator ABSOLUTE MAXIMUM RATINGS (Full Operating Ambient Temperature Range Applies Unless Otherwise Noted) CHARACTERISTIC Cathode Voltage Continuous Cathode Current Range Reference Input Current Range Junction Temperature Operating Temperature Storage Temperature Total Power Dissipation SYMBOL VKA IKA IREF TJ TOPR TSTG PD RATING 15 100 -0.05 ~ 3 -40 ~ 150 0 ~70 -65~+150 770 TL432/ A / C UNIT V ㎃ ㎃ ℃ ℃ ℃ ㎽ TL432A/C ELECTRICAL CHARACTERISTICS CHARACTERISTIC Reference Input Voltage Deviation of Reference Input Voltage Over Full Temperature Range Ratio of Change in Reference Input Voltage ΔVREF/ΔVKA (TA=25℃, unless otherwise specified) TEST CONDITION VKA=VREF, IK=10㎃ VKA=VREF, IK=10㎃ TL432A TL432C MIN. 1.228 1.24 1.233 1.247 TYP. MAX. 1.252 V UNIT SYMBOL VREF ΔVREF/ΔT TA=Full Range 10 25 ㎷ to the Change in Cathod Voltage Reference Input Current Deviation of Reference Input Current Over Full Temperature Range Minimum Cathode Current for Regulation Off-State Cathode Current Dynamic Impedance IKAMIN ΔIREF/ΔT IREF VKA=1.25V to 14.5V 1.0 2.7 ㎷/V R1=10㏀, R2=∞ 0.5 1 ㎂ R1=10㏀, R2=∞, Ta = Full Range 0.05 0.3 ㎂ Vka=Vref 60 80 ㎂ IKAOFF VKA=15V, V REF=0 0.04 0.5 ㎂ ZKA VKA=VREF, IK=0.1㎃~20㎃, f≤1.0㎑ 0.2 0.4 Ω HTC 23 Low Voltage(1.24V) Adjustable Precision Shunt Regulator TL432/ A / C Fig. 1 Test Circuit for V KA =V REF Fig. 2 Test Circuit for V KA ≥V REF INPUT IKA VKA INPUT IKA VKA R1 DUT ＩREF DUT VREF 1 uF R2 VREF VKA=VREF(1+R1/R2)+IREF R1 Fig. ３ Test Circuit for IKA （off) INPUT IKA(OFF) VKA DUT Jan, 2004 - Rev 01 HTC 24 Low Voltage(1.24V) Adjustable Precision Shunt Regulator TL432/ A / C The deviation parameters V REF(DEV) and IREF(DEF) are defined as the differences between the maximum and minimum values obtained over the recommended temperature range. The average full-range temperature coefficient of the reference voltage, αV REF, is defined as : Maximum V REF V I(dev) 6 （ ）x10 ppm VREF at 25℃ ｜αVREF｜ （ ）= ℃ ΔTA VI(dev) Minimum V REF ΔTA Where : ΔTA is the recommended operating free-air temperature range of the device. αVREF can be positive or negative, depending on whether minimum V REF or maximum V REF, respectively, occurs at the lower temperature. Example : Maximum V REF=1190㎷ at 30℃, maximum VREF=1262㎷ at 0℃, VREF=1241㎷ at 25℃, ΔTA=125℃ for TL431C （ 7.2㎷ x106 ） ~ 46PPM/℃ 1241㎷ ~ 125℃ ｜αVREF｜= Because minimum V REF occurs at the lower temperature, the coefficient is positive. Calculating Dynamic Impedance The dynamic impedance is defined as : ｜ZKA｜= ΔVKA ΔIKA When the device is operating with two external resistors (see Figure 3), the total dynamic impedance of the circuit is given by : ΔV ΔI ~｜ZKA｜ （1+ R1 ） ~ R2 ｜Z'｜= Jan, 2004 - Rev 01 HTC 25