AN1432MSAN1432MS, Serwisówki TV, Układy Scalone
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Voltage Regulators AN1432MS Variable output, low voltage operation shunt regulator Overview The AN1432MS is a low voltage operation and posi- tive voltage variable output type shunt regulator. Since the output voltage is adjustable from approximately 1.26 V to 15 V, it is suitable for a power supply of small-sized 3 V- system portable equipment. Also, it contributes to the min- iaturization of set equipment by the adoption of the small type surface mounting package. Unit: mm 0.65±0.15 2.80 +0.20 –0.30 1.50 +0.25 –0.05 0.65±0.15 1 3 Features • High accuracy reference voltage: 1.26 V (allowance: ±2%) • Low voltage operation: 1.26 V to 15 V • Small type surface mounting package 2 0.10 to 0.30 0.40±0.20 Applications • Portable telephone, PHS, office automation equipment and other small-sized portable equipment MINI-3D Block Diagram K 2 Constant current source Ref. 1 Error amplifier Output transistor Reference voltage 3 A 1 AN1432MS Voltage Regulators Pin Descriptions Pin No. Description 1 Reference The reference voltage (1.26 V typical) pin. Although the impedance is high under the no- rmal using conditions, be careful that the impedance drops and current flo ws into the IC inside if a current or voltage is forced to apply from the outside. 2 K: Cathode The pin for the combined use of the power source current supply of IC and the constant voltage output as the shunt regulator. An excessive current supplied to this pin is bypassed to the anode pin through the output transistor. 3 Anode The constant voltage reference pin of the shunt regulator, and the current from the cathode and reference flows out. Usually grounded. Absolute Maximum Ratings Parameter Symbol Rating Unit Supply voltage V K 15 V Reference voltage V REF 7 V Supply current I K 20 mA Reference current I REF 50 µA Cathode anode reverse current −I KA −10 mA Cathode reference reverse current −I KR −10 mA Power dissipation * 2 P D 104 mW Operating ambient temperature * 1 T opr −30 to +85 °C Storage temperature * 1 T stg −55 to +150 °C Note) 1. Do not apply external currents or voltages to any pins not specifically mentioned. For circuit currents, '+' denotes current flowing into the IC and '−' denotes current flowing out of the IC. 2. * 1: Except for the power dissipation, operating ambient temperature and storage temperature, all ratings are for T a = 25°C. * 2: The value at T a = 85°C. Recommended Operating Range Parameter Symbol Range Unit Supply voltage V CC V REF to 15 V Electrical Characteristics at T a = 25 ° C Parameter Symbol Conditions Min Typ Max Unit Reference voltage V REF V KA = V REF , I K = 10 mA 1.235 1.26 1.285 V Reference voltage fluctuation 1 ∆V REF / V REF ≤ V KA ≤ 5 V, 1.9 3.5 mV/V ∆V KA I K = 10 mA Reference voltage fluctuation 2 ∆V REF /5 V ≤ V KA ≤ 15 V, 1.0 2.0 mV/V ∆V KA I K = 10 mA Reference input current I REF R I = 10 k Ω , I K = 10 mA 2.5 4.4 µ A Minimum cathode current I K min V KA = V REF 290 350 µ A Off time cathode current I K OFF V KA = 15 V, V REF = 0 V 1.0 µ A Dynamic impedance Z KA V KA = V REF , f ≤ 1 kHz, 0.1 0.5 Ω I K = 1 mA to 10 mA 2 Voltage Regulators AN1432MS Electrical Characteristics at T a = 25 ° C (continued) • Design reference data Note) The characteristics listed below are theoretical values based on the IC design and are not guaranteed. Parameter Symbol Conditions Reference value Unit Reference voltage change ∆V REF /V KA = V REF , I KA = 10 mA 3 mV with temperature ∆T a 0 °C ≤ T a ≤ +70 °C Reference input current change ∆I REF / R 1 =10 kΩ, I K = 10 mA 0.4 µA with temperature ∆T a 0 °C ≤ T a ≤ +70 °C Application Notes • P D T a curve of MINI-3D P D T a 200 175 Independent IC without heat sink R th(j-a) = 625 ° C/W P D 200 mW (25 C) 150 125 104 75 50 25 0 0 25 50 75 85 100 125 150 Ambient temperature T a ( ° C) Application Circuit Example This circuit amplifies the error voltage of the secondary side output voltage in the insulation type switching power supply, then transfers it to the primary side via a photocoupler. Replaceable with the conventional product (AN1431M, AN1431T). (Primary side) (Secondary side) V OUT AN1432MS Primary side to control IC 3 = ° 100 [ Pobierz całość w formacie PDF ] |
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