ME431精密可调分流调节阀.pdf

ME431 V03 Page 1 of 12 Adjustable Precision Shunt Regulator General Description Features Selection Guide The ME431 series ICs are three-terminal adjustable shunt regulators with guaranteed thermal stability over a full operation range.These ICs feature sharp turn-on characteristics,low temperature coefficient and low output impedance,which make them ideal substitutes for Zener diodes in applications such as switching power supply,charger and other adjustable regulators.The ME431 voltage type is 40V.The output voltage can be set to any value between VREF(2.5V)and the corresponding maximum cathode voltage.The ME431 precision reference is offered in two band gap tolerance:0.4%and 1.0%.Programmable Precise Output Voltage from 2.5V to 36V Very Accurate Reference Voltage:Typical 0.15%High Stability under Capacitive Load Low Temperature Deviation:Typical 4.5mV Low Equivalent Full-range Temperature Coefficient with 20PPM/Typical Low Dynamic Output Resistance:Typical 0.2 Sink Current Capacity from 1mA to 100 mA Low Output Noise Wide Operating Range of-40 to 150 TO-92,SOT23-3,SOT23 package Typical Application Charger Voltage Adapter Switching Power Supply Graphic Card Precision Voltage Reference Selection Guide Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 2 of 12 PIN Configuration Block Diagram and symbol Absolute Maximum Ratings PARAMETER SYMBAL RATING UNIT Cathode voltage VKA 40 V Cathode current range(continuous)IKA-100 to+130 mA Reference input current range IREF 10 mA Power Dissipation PD TO-92 Package:770 mW SOT23-3 Package:370 SOT23 Package:300 Junction temperature TJ 160 Storage Temperature range TSTG-65+150 Package thermal impedance JA TO-92 package:150/W SOT23-3 package:330 SOT23 package:350 Note:Use this IC within the stated maximum ratings.Operation beyond these limits may cause degrading or permanent damage to the device.TO-92 CATHODE REF ANODE VREF CATHODE REF ANODE SOT23-3 SOT23 Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 3 of 12 Recommended Operating Conditions Parameter Symbol Min Max Unit Cathode Voltage VKA VREF 36 V Cathode Current IKA 1.0 100 mA Operating Ambient Temperature Range -40 125 Electrical Characteristics (TA=25,unless otherwise noted)Parameter Symbol Conditions Min Typ.Max Unit Test circuit Reference voltage 0.4%VREF VKA=VREF,IKA=10mA 2.490 2.50 2.510 V Fig.1 1.0%2.475 2.50 2.525 Deviation of reference voltage over-temperature VREF VKA=VREF,IKA=10mA 0 to 70-3 10 mV Fig.1-40 to 150-3 15 Dynamic impedance KA|Z|VKA=VREF,IKA=1 to 100mA,f1.0KHz-0.15 0.5 Fig.1 Minimum cathode current for regulation IKA(MIN)VKA=VREF-0.4 1.0 mA Fig.1 Ratio of change in reference voltage to the change in cathode voltage REFKAVV IKA=10mA VKA=10V to VREF-0.8-2.5 mV/V Fig.2 VKA=36V to 10V-0.6-1.5 Reference current IREF IKA=10mA,R1=10K,R2=0.7 3 A Fig.2 Deviation of reference over full temperature range IREF IKA=10mA,R1=10K,R2=,TA=40 to 150 0.1 1.2 A Fig.2 Off-state cathode current IKA(OFF)VKA=36V,VREF=0 0.03 0.3 A Fig.3 Note:The dynamic impedance is defined as:KA|Z|=VKA/IKA K AR E FR E FV=V(1+R1/R2)+IR1 Fig.1:for VKA=VREF Fig.2:for VKA VREF Fig.3:for IOFF R1 VIN VKA IKA VREF VIN VKA IKA VREF R1 R2 R3 R1 VIN VKA IOFF Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 4 of 12 Typical Performance Characteristics VKA=VREF IKA=10mA VKA=36V VREF=0 R1=10K IKA=10mA VKA=VREF TA=25 VKA=VREF TA=25 VKA=3.5V to 36V Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 5 of 12 Small Signal Voltage Gain vs.Frequency Reference Impedance vs.Frequency Stability Boundary Conditions vs.Load Capacitance 10F 15K 8.2K 242 IKA GND ME431 GND Output Output IKA 1K 50 R1 10K R2 IKA 150 ME431 Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 6 of 12 Pulse Response of Input and Output Voltage Typical Application Fig.4:Shunt Regulator Fig.5:High Current Shunt Regulator GND Output 220 50 F=100KHz Generator Pulse VIN R3 R1 R2 VREF VOUT ME431 VO=(1+R1/R2)VREF VIN R1 R2 R3 VREF ME431 R4 VOUT VO=(1+R2/R3)VREF Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 7 of 12 Fig.6:Current Source or Current Limit Fig.7:Precision 5V 1.5A Regulator VIN R1 R2 ME431 IOUT IOUT=VREF/R2+IKA VIN R1 8.2K R2 250 R3 250 VOUT 5V,1.5A ME431 ME1117 Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 8 of 12 Packaging Type:TO-92 Min Max Min Max A 3.4 3.8 0.13386 0.1496 B 0.3 0.5 0.0118 0.0197 C 4.4 4.8 0.1732 0.189 D 4.4 4.8 0.1732 0.189 E 0.9 1.5 0.0354 0.059 e 1.17 1.37 0.046 0.0539 e1 2.39 2.69 0.094 0.1059 L 12 16 0.4724 0.6299 Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 9 of 12 Packaging Type:TO-92(Paper Tape)单位：单位：mm Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 10 of 12 Packaging Type:SOT23-3 DIM Millimeters Inches Min Max Min Max A 2.7 3.1 0.1063 0.122 B 1.7 2.1 0.0669 0.0827 b 0.35 0.5 0.0138 0.0197 C 1.0 1.2 0.0394 0.0472 c 0.1 0.25 0.0039 0.0098 d 0.2-0.0079-E 2.6 3.0 0.1023 0.1181 e 1.5 1.8 0.059 0.0708 Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2 ME431 V03 Page 11 of 12 Packaging Type:SOT23 DIM Millimeters Inches Min Max Min Max A 2.7 3.1 0.1063 0.122 B 1.7 2.1 0.0669 0.0827 b 0.35 0.5 0.0138 0.0197 C 1.0 1.2 0.0394 0.0472 c 0.1 0.25 0.0039 0.0098 d 0.2-0.0079-E 2.1 2.64 0.0827 0.1039 e 1.2 1.4 0.0472 0.0551 Q、2 3 5 5 5 5 8 4 6 0 1 3 6 2 0 9 7 1 6 5 2