AP431A

AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Features • Precision reference voltage AP431 : 2.495V ± 1% AP431A : 2.495V ± 0.5% Sink current capability: 200mA Minimum cathode current for regulation: 300µA o Equivalent full-range temp coefficient: 30 ppm/ C Fast turn-on response Low dynamic output impedance: 0.2Ω Programmable output voltage to 36V Low output noise Packages: SOT23, SOT23R, SOT25, SC59 (W package code), SC59 (R package code), SOP-8L and TO92-3L SOT23, SOT23R, SOP-8L and SC59: Available in “Green” Molding Compound (No Br, Sb) (Note 1) Lead Free Finish/RoHS Compliant for Lead Free and “Green” Products (Note 2) General Description The AP431 and AP431A are 3-terminal adjustable precision shunt regulators with guaranteed temperature stability over the applicable extended commercial temperature range. The output voltage may be set at any level greater than 2.495V (VREF) up to 36V merely by selecting two external resistors that act as a voltage divider network. These devices have a typical output impedance of 0.2Ω. Active output circuitry provides very sharp turn-on characteristics, making these devices excellent improved replacements for Zener diodes in many applications. The precise (+/-) 1% Reference voltage tolerance of the AP431/AP431A make it possible in many applications to avoid the use of a variable resistor, consequently saving cost and eliminating drift and reliability problems associated with it. • • • • • • • • • • Ordering Information A P 4 3 1X X X X Reference Voltage Tolerance: Blank : +/- 1% A : +/- 0.5% Package Blank : V : SA : W : R : : Q SR : SOP-8L TO92-3L SOT23 SC59 SC59 SOT25 SOT23R Lead-Free L : Lead Free G : Green (Note 1) Packing -B : Bulk -7/-13 : Taping -A : Ammo Box (Note 3) Note: 1. SOT23, SOT23R are “Green” products only. 2. RoHS revision 13.2.2003. Glass and High Temperature Solder Exemptions Applied, see EU Directive Annex Notes 5 and 7. Device (Note 4) AP431(A)SA AP431(A)SR Lead-free 7” Tape and Reel 13” Tape and Reel Ammo Box Package Packaging Part Number Part Number Part Number Code (Note 5) Quantity Quantity Quantity Suffix Suffix Suffix SA SR Q W R SOT23 SOT23R SOT25 SC59 SC59 SOP-8L V TO92-3L 3000/Tape & Reel 3000/Tape & Reel 3000/Tape & Reel 3000/Tape & Reel 3000/Tape & Reel NA NA -7 -7 -7 -7 -7 NA NA NA NA NA NA NA 2500/Tape & Reel NA NA NA NA NA NA -13 NA NA NA NA NA NA NA 2000/Box NA NA NA NA NA NA -A AP431(A)Q AP431(A)W AP431(A)R AP431(A) Lead-free AP431(A)V Notes: 3. Ammo Box is for TO92-3 Spread Lead. 4. Suffix “A” denotes AP431A device. 5. Pad layout as shown on Diodes Inc. suggested pad layout document AP02001, which can be found on our website at http://www.diodes.com/datasheets/ap02001.pdf. AP431/AP431A Rev. 5 1 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Pin Assignment Package Pin Configuration (Top View) NC 1 2 4 CATHODE 3 REF Package Pin Configuration (Top View) CATHODE 1 2 3 4 8 7 6 5 REF ANODE ANODE NC 5 ANODE SOP-8L SOT25 NC ANODE ANODE NC SC-59 ( Package Code-W) 3 ANODE 1 2 REF SOT23 CATHODE ANODE 1 3 REF 2 CATHODE 3 SC-59 ( Package Code-R) 3 ANODE 1 2 REF CATHODE SOT23R ANODE 1 2 CATHODE REF 3 Cathode 2 Anode 1 REF AP431/AP431A Rev. 5 + + TO92-3L + 2 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Typical Application Circuit VIN VOUT + Cin AP431 R1 + Cout R2 VOUT = (1+R1/R2)VREF Precision Regulator Block Diagram REF (R) + Cathode (C) Anode (A) VREF Symbol Cathode (C) REF (R) Anode (A) AP431/AP431A Rev. 5 3 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Absolute Maximum Ratings Symbol Vcv ICC IREF TOP TST Parameter Cathode Voltage Continuous Cathode Current Reference Input Current Operating Temperature Storage Temperature SOT23(R) SOT25 Power Dissipation SC59 (Notes 6, 7) SOP-8L TO92-3L Rating +36 -10 to +250 10 -20 to +85 -65 to +150 250 250 400 600 780 Unit V mA mA o C o C mW mW mW mW mW PD Note: 6. TJ, max =150°C 7. Ratings apply to ambient temperature at 25°C AP431/AP431A Rev. 5 4 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Electrical Characteristics PARAMETER Reference voltage Deviation of Reference input voltage over temperature (Note 8) Ratio of the change in Reference voltage to the change in Cathode voltage Reference input current Deviation of Reference input current over temperature Minimum Cathode current for regulation Off-state current Dynamic output impedance (Note 9) ( TA = 25oC, V+ = +5.0V, unless otherwise stated ) TEST CONDITIONS AP431 VKA = VREF, AP431A I KA = 10mA (Fig.1) VKA = VREF, IKA = 10mA, Ta = Full range (Fig.1) VKA = 10V ~VREF IKA = 10mA (Fig. 2) VKA= 36V ~10V R1 = 10KΩ,R2 = ∞ IKA= 10mA (Fig. 2) R1 = 10KΩ,R2 = ∞ IKA = 10mA Ta = Full range (Fig. 2) VKA = VREF (Fig.1) VKA = 36V, VREF = 0V (Fig. 3) V KA = VREF V KA = VREF ∆IKA = 0.1mA ~ 15mA Frequency ≤ 1KHz (Fig.1) SYMBOL MIN. VREF VREF ∆VREF ∆VKA IREF αIREF IKA(MIN) IKA(OFF) |ZKA| 2.470 2.482 ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ ⎯ TYP. MAX. UNIT 2.495 8.0 -1.4 -1 1.4 0.4 0.19 0.1 0.2 2.520 2.507 20 -2.0 -2 3.5 1.2 0.5 1.0 0.5 V mV mV/V mV/V µA µA mA µA Ω VMAX VDEV = VMAX - VMIN VMIN TI Temperature T2 Note: 8. Deviation of reference input voltage, VDEV, is defined as the maximum variation of the reference over the full temperature range. The average temperature coefficient of the reference input voltage αVREF is defined as: α VREF VDEV ) ⋅10 6 VREF (25°C) ……………………..……………….. ( ppm ) = °C T2 − T1 ( Where: T2 – T1 = full temperature change. αVREF can be positive or negative depending on whether the slope is positive or negative. Note: 9. The dynamic output impedance, RZ, is defined as: Z KA = ∆ V KA ∆ IKA When the device is programmed with two external resistors R1 and R2 (see Figure 2.), the dynamic output impedance of the overall circuit, is defined as: Z KA = ' ∆v ≈ Z KA ∆i (1 + R1 ) R2 AP431/AP431A Rev. 5 5 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Test Circuits Input IN IN VKA IKA R1 VREF IREF VREF IKA VKA VKA R2 IZ(OFF) Note:VKA=VREF(1+R1/R2)+IREFxR1 Fig 1. Test Circuit for VKA= VREF Fig 2. Test Circuit for VKA > VREF Fig 3. Test Circuit for Off-State Current AP431/AP431A Rev. 5 6 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Typical Performance Characteristics Cathode Current vs Cathode Voltage 100 VKA =Vref Ta=25oC Cathode Current (uA) 600 VKA =Vref Ta=25oC Cathode Current (uA) vs Cathode Voltage Cathode Current (mA) 400 0 200 0 -100 -1.5 0.5 -0.5 1.5 Cathode Voltage (v) 2.5 -200 -1 -0.5 0 0.5 1.5 1 Cathode Voltage(v) 2 2.5 Reference Voltage vs Free-Air Temperature Reference Input Current (uA) 2500 Reference Voltage (mV) 2495 2490 2485 2480 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 Free-Air Temperature (oC) Reference Input Current vs Free Temperature 2 1.8 1.6 1.4 1.2 1 -50 R1=10K IKA=10mA -25 0 25 50 75 Free-Air Temperature (oC) 100 125 Change in Reference Voltage vs Cathode Voltage Change in Reference Voltage (mv) 0 -2 -4 -6 -8 -10 -12 0 5 10 15 20 Cathode Voltage (V) 25 30 IKA=10mA Ta=25oC AP431/AP431A Rev. 5 7 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Typical Performance Characteristics Small-Signal Voltage Amplification vs Frequency 60 ( Continued ) AV-Small Signal Voltage Amplification (dB) 50 40 30 20 10 0 1K 10K IKA=10mA TA=25oC 15KΩ 9µF Output IKA 232Ω + 8.25KΩ - Test Circuit for Voltage Amplification f-Frequency-Hz 100K 1M 10M Reference Impedance vs Frequency 100 I KA=10mA o TA =25 C | ZKA | Reference Impedance (Ω) 10 50Ω + 1 Test Circuit for Reference Impedance 0.1 1K 10K 100K 1M 10M f-Frequency-Hz AP431/AP431A Rev. 5 8 of 14 www.diodes.com 1KΩ + GND Output I KA GND MARCH 2007 © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Typical Performance Characteristics Pulse Response 6 TA=25oC ( Continued ) 5 Input and Output Voltage-V Input 220Ω Output 4 Pulse Generator f=100kHz 50Ω 3 Output GND 2 Test Circuit for Pulse Response 1 0 -1 0 1 2 3 t-Time-µS 4 5 6 7 STABILITY BOUNDARY CONDITIONS† 100 90 80 IKA-Cathode Current-mA 70 60 50 40 30 20 10 0 0.001 0.01 0.1 1 C L-Load Capacitance-µF 10 CL R2 150Ω I KA CL A VKA=Vref B VKA=5V C VKA=10V D VKA=15V B TA=25oC + - VBATT Stable Stable A C Test Circuit for Curve A D R1=10KΩ I KA 150Ω + - VBATT The areas under the curves represent conditions that may cause the device to oscillate. For curves B, C, and D, R2 and V+ were adjusted to establish the initial V KA a nd I KA c onditions with C L =0.V BATT a nd CL were then adjusted to determine the ranges of stability. Test Circuit for Curve B, C, and D AP431/AP431A Rev. 5 9 of 14 MARCH 2007 www.diodes.com © Diodes Incorporated AP431/AP431A ADJUSTABLE PRECISION SHUNT REGULATOR Application Examples V IN VIN R CL R R1A R1B V IN I OUT R2A R2B OFF O N + LED on when Low Limit < VIN < High Limit Low Limit ≈ VREF (1+R1B/R2B) High Limit ≈ VREF (1+R1A/R2A) Delay = RC x ln ( VIN ) V IN -VREF I OUT = V REF / RCL Fig. 4 Voltage Monitor V IN I OUT Fig. 5 Delay Timer Fig. 6 Current Limiter or Current Source V IN R 1 V OUT V IN PULSE R 1 V OUT RS R 2 R 2 I OUT = V REF / RS V OUT = (1 + R1/R2) x VREF LIMIT (1 + R1/R2) x VREF Fig. 7 Constant-Current Sink Fig. 8 Higher-Current Shunt Regulator Fig. 9 Crow Bar VIN R1A R1B Output ON when Low Limit