AN1431T

AN1431T, AN1431M Surface-mount Adjustable Output Shunt Regulator s Overview The AN1431T and AN1431M are high accuracy stabilized power supplies in which the output voltage can be adjusted in the range from approx. 2.5 to 36V by using the external resistor under the operating temperature. Because of its fast rise characteristics, it can be replaced with Zener diode and has the wide application range. AN1431T 5.0±0.2 5.1±0.2 4.0±0.2 Unit : mm s Features • High precision reference voltage : 2.5V±2% • High-temperature stability : 17ppm/˚C typ. • Output voltage externally adjustable : 2.5 to 36V • Fast rise • Low input impedance : 0.2Ω (typ.) • Low output noise voltage 0.45 – 0.1 2.54 2.3±0.2 231 JEDEC : TO-92 (SSIP003-P-0000) s Pin Name 〈AN1431T〉 Pin No. 1 2 3 Cathode Reference pin Anode Pin name AN1431M 5.0±0.2 5.1±0.2 4.0±0.2 13.5±0.5 +0.2 Unit : mm 〈AN1431M〉 Pin No. 1 2 3 Anode Cathode 231 Pin name Reference pin 2.54 0.45 – 0.1 2.3±0.2 +0.2 s Block Diagram JEDEC : TO-92 (SSIP003-P-0000) Current Source Output Tr + Error Amp. – Voltage Reference VKA = VREF (1 + R2 = 2.5kΩ R1 R2 ) + IREF · R1 1 3 IK 3 2 1 2 IREF VKA VREF V1 R1 R2 Pin number in Pin number in is for the AN1431T. is for the AN1431M. 13.5±0.5 s Absolute Maximum Ratings (Ta=25˚C) Parameter Supply voltage Supply current Power dissipation Reference input current Operating ambient temperature Storage temperature AN1431T AN1431M AN1431T AN1431M Symbol VCC ICC PD IREF Vopr Tstg Rating 37 –100 to+150 650 * – 0.05 to+10 –20 to+85 –25 to+80 –55 to+150 –55 to+125 Unit V mA mW mA ˚C ˚C * For the AN1431M, SM to the printed board (glass epoxy of 20 × 20 × 1.7mm with copper film of 1cm2) s Recommended Operating Range (Ta=25˚C) Parameter Operating supply voltage range Symbol VKA Range VREF (2.5 to 36V) s Electrical Characteristics (Ta=25˚C) Parameter Reference voltage Reference voltage temperature deviation Reference voltage fluctuation Reference input current Reference input current temperature deviation Minimum cathode current Off-state cathode current Dynamic impedance Symbol VREF VREF (Jev) *1 *2 ∆VREF ∆VKA IREF IREF (Jev) * Imin IOFF |ZKA| *3 2 Condition VKA=VREF, IK=10mA VKA=VREF, IK=10mA, Ta=0 to+70˚C IK=10mA, DVKA=10V to VREF IK=10mA, DVKA=36 to 10V IK=10mA, R1=10kΩ, R2= ∞ IK=10mA, R1=10kΩ, R2= ∞, Ta=0 to+70˚C VKA=VREF VKA=36V, VREF=0V VKA=VREF, IK=1 to 100mA, f < 1kHz = min 2.45 typ 2.50 3 –1.2 –1 2 0.4 0.4 0.1 0.2 max 2.55 17 –2.7 –2 4 1.2 1.0 1.0 0.5 Unit V mV mV/V mV/V µA µA mA µA Ω *1 VREF VREF (dev) = VREF (max) –VREF (min) The temperature coefficient aVREF for the reference input voltage is equivalently given by the following expression. VREF (dev) VREF* × 106 (ppm/˚C) ∆Ta VREF (max) |aVREF|= VREF (dev) VREF at Ta=25˚C For example, assuming the following ; VREF (max) =2500mV (Ta=30˚C), VREF (min) =2497mV (Ta=0˚C), (VREF (dev) =3mV), VREF=2499mV (Ta=25˚C) ∆Ta=70˚C Then, the following expression is established. 3mV |aVREF| = 2499mV × 106=17.1 (ppm/˚C) 70˚C *2 These values are design reference values, not guaranteed ones. *3 The dynamic impedance is defined by the following expression. |ZKA| = ∆VKA ∆IK * VREF (min) ∆Ta IREF IREF (dev) = IREF (max) – IREF (min) IREF (max) IREF (dev) IREF (min) ∆Ta The total dynamic impedance at ∆VREF, ∆VKA, IREF, and IREF (dev) is as follows. ∆V R1 |Z| = ∆I = |ZKA| 1 + R 2 s Power Dissipation PD – Ta 1000 900 Mounting onto Substrate : 20 × 20 × 1.7mm Glass Epoxy Substrate, Copper Foil 1cm2 or More Power Dissipation PD (mW) 800 700 600 500 400 300 200 100 0 0 20 40 60 80 100 120 140 160 Ambient Temperature Ta (˚C) s Application Circuits 1.Shunt Regulator +V VO 2.Constant Current Power Supply +V IO 3.Constant Current Source +V R1 VREF R2 AN1431T/M AN1431T/M AN1431T/M RS RS VO = 1+ R1 V R2 REF IO = VREF RS IO = VREF RS IO 4.Current Boost +V VO 5.Adjustable Output Regulator Combined with 3-pin Regulator +V VO AN7805 R1 R1 VREF R2 AN1431T/M CI AN1431T/M VREF CO R2 VO = 1+ R1 V R2 REF VO = VREF 1+ R1 = VREF + 5V V R2 O (min) s Characteristics Curve VREF – Ta 2700 2650 2600 2550 2500 2450 2400 2350 –50 –25 4 IREF – Ta Reference Input Current IREF (µA) IK=10mA R1=10kΩ R2= ∞ 3 VK=VREF IK=10mA Reference Voltage VREF (mV) 2 1 0 25 50 75 100 125 –40 –20 0 20 40 60 80 100 Ambient Temperature Ta (˚C) Ambient Temperature Ta (˚C)