SPX2431

® SPX2431 Precision Adjustable Shunt Regulator FEATURES ■ Trimmed Bandgap to 0.5% and 1.0% ■ Wide Operating Current 1mA to 100mA ■ Extended Temp. Range: 0°C to 105°C ■ Low Temperature Coefficient 30 ppm/°C ■ Offered in 3 Pin SOT-23 (M) ■ Replacement for TL431, AS2431 ■ Low Noise Output APPLICATIONS ■ Battery Operating Equipment ■ Adjustable Supplies ■ Switching Power Supplies ■ ■ ■ ■ ANODE 3 SPX2431 3 Pin SOT-23 1 REF Top View 2 CATHODE Now Available in Lead Free Packaging Error Amplifiers Single Supply Amplifier Monitors / VCRs / TVs Personal Computers DESCRIPTION The SPX2431 is a 3-terminal adjustable shunt voltage regulator providing a highly accurate bandgap reference. The SPX2431 acts as an open-loop error amplifier with a 2.5V temperature compensation reference. The SPX2431’s thermal stability, wide operating current (100mA) and temperature range (0°C to 105°C) makes it suitable for a variety of applications that require a low cost, high performance solution. SPX2431A tolerance of 0.5% is proven to be sufficient to overcome all of the other errors in the system to virtually eliminate the need for trimming in the power supply manufacturer's assembly line and contribute a significant cost savings. The output voltage may be adjusted to any value between VREF and 20 volts with two external resistors. In the standard shunt configuration, the combination of a low temperature coefficient, sharp turn on characteristics, low output impedance, and programmable output voltage makes this precision reference an excellent error amplifier. The SPX2431 is available in SOT-23-3 package. FUNCTIONAL DIAGRAM Cathode (K) Reference (R) + 2.5V Anode (A) Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 1 ABSOLUTE MAXIMUM RATINGS Cathode-Anode Reverse Breakdown VKA ....................................... 20V Anode-Cathode Forward Current, (25°. ELECTRICAL CHARACTERISTICS Electrical characteristics at 25°C IK = 10mA VK = VREF, unless otherwise specified. PARAMETER SYMBOL FIGURE CONDITIONS MIN TYP SPX2431A Reference Voltage ∆VREF withTemp.* Ratio of Change in VREF to Cathode Voltage Reference Input Current IREF Temp Deviation Min IK for Regulation Off State Leakage Dynamic Output Impedance VREF TC ∆ VREF ∆ VK IREF ∆IREF IK(MIN) IK(OFF) 4 ZKA 2 2 2 2 3 3 3 2 VREF = 0V, VKA = 20V ƒz ≤ 1kHz IK = 1 to 100mA TJ = 0°C to 105°C VREF to 10V 10V to 20V -2.7 -2.0 TJ = 0°C to 105°C 2.487 2.480 2.500 0.07 -1.01 -0.4 0.7 0.4 0.4 0.04 0.15 0.5 2.513 2.520 0.20 0.3 4.0 1.2 1.0 -2.7 -2.0 2.474 2.460 MAX MIN TYP SPX2431 2.500 0.07 -1.01 -0.4 0.7 0.4 0.4 0.04 0.15 2.526 2.540 0.20 0.3 4.0 1.2 1.0 500 0.5 µA µA mA nA Ω V V mV/°C mV/V MAX UNITS Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 2 CALCULATING AVERAGE TEMPERATURE COEFFICIENT (TC) ppm 0 % 0 mV 0 ∆VREF ∆T -5 • TC in mV / °C = ∆VREF(mV) ∆TA • TC in % / °C = ( ∆VREF ∆VREF at 25°C ∆ TA ) x 100 5000 0.5 0 15 30 45 60 75 90 105 • TC in ppm / °C = ( ∆VREF ∆VREF at 25°C ∆TA ) x 106 Junction Temperature (°C) 0.0033mV /°C 0.0027% / °C 27ppm/°C Figure 1. VREF VS Temperature TEST CIRCUITS VIN VKA = VREF VIN VKA VIN VKA IK (OFF) IREF IK R1 IREF (VREF) R2 IK Figure 2. Test Circuit for VKA = VREF Figure 3. Test Circuit for VKA > VREF Figure 4. Test Circuit for IKOFF Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 3 TYPICAL PERFORMANCE CHARACTERISTICS 150 125 100 VKA = VREF 0°C to 105°C 2.53 2.52 VKA = VREF IK = 10mA VREF Reference Voltage (V) 3 IK Cathode Current (mA) 2.51 2.50 2.49 2.48 2.47 2.46 2.45 -60 75 50 25 0 -25 -50 -75 -100 -2 -1 0 1 2 VKA Cathode Voltage (V) -30 0 30 60 90 120 TA Ambient Temperature (°C) Figure 5. High Current Operating Characteristics Figure 6. Reference Voltage VS Ambient Tempetature 900 3.0 700 IREF Reference Input Current (µA) 800 VKA = VREF 0° to 105°C 2.5 2.0 1.5 1.0 0.5 0 -60 R1 = 10kΩ R2 = ∞ IK = 10mA IK Cathode Current (µA) 600 500 400 300 200 100 0 -100 -200 -1.0 1.0 2.0 VKA Cathode Voltage (V) 0 3.0 105°C 25°C -0°C -30 0 30 60 90 120 TA Ambient Temperature (°C) Figure 7. Low Current Operating Characteristics Figure 8. Reference Input Current VS Ambient Temperature 70 60 0 0°C ∆VREF (mV) Noise Voltage n/√Hz -10 50 40 30 20 10 0 10 VKA = VREF IK = 10mA TA = 25°C 100 1K 10K 100K -20 25°C 75°C -30 IKA = 10mA -40 125°C -50 0 3 6 9 12 15 18 21 24 27 30 VKA Cathode Voltage (V) f Frequency (Hz) Figure 9. Reference Voltage Line Regulation VS Cathode Voltage and TAMBIENT Figure 10. Noise Voltage VS Frequency Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 4 TYPICAL PERFORMANCE CHARACTERISTICS: Continued 0.150 REF LEVEL 60.000dB 0.0deg /DIV 10.000dB 45.000deg MARKER 25 297 698.000 Hz MAG (A/R) -0.025 dB MARKER 25 297 698.000 Hz PHASE (A/R) 93.320 deg 215° 180° PHASE 135° 90° 45° 0° GAIN 0dB -10dB -20dB -45° -90° -135° -180° -215° ZKA Dynamic Impedance (Ω) 0.125 0.100 0.075 0.050 0.025 0.0 -60 VKA = VREF IK = 1 to 100mA f≤1kHz 60dB 50dB 40dB 30dB 20dB 10dB -30dB -30 0 30 60 90 120 -40dB 10 100 1K 10K 100K 1M 10M TA Free Air Temperature START 10.000Hz STOP 50 000 000.000Hz Figure 11. Low Frequency Dynamic Output Impedance VS TAMBIENT Figure 12. Small Signal Gain and Phase VS Frequency; IK = 10mA, TA = 25°C VOUT VIN 230Ω 9µF 15kΩ IK VOUT VIN 8.25kΩ GND Figure 13. Test Circuit for Gain and Phase Frequency Response VIN 250Ω Figure 14. Frequency = 100kHz, IK = 10mA, TA = 25°C 100 90 IK Cathode Current (mA) A: VKA = VREF B: VKA= 5V at IK=10mA C: VKA=10V at IK=10mA D: VKA=15V at IK=10mA C VOUT IK fp = 100kHz 50Ω 80 70 60 50 40 STABLE A STABLE 30 20 10 0 100 TA = 25°C B D GND 101 102 103 104 105 106 107 CL Load Capacitance (pF) Figure 15. Test Circuit for Pulse Response Figure 16. Stability Boundary Conditions Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 5 TYPICAL PERFORMANCE CHARACTERISTICS 100 150 Ω IK R ZKA Dynamic Impedance (Ω) TA = 25°C IK = 1 to 100mA 10 CL 1.0 10kΩ 0.1 0.01 1K 10K 100K 1M f Frecuency (Hz) 10M Figure 17. Test Circuit for Stability Figure 18. Dynamic Output Impedance TA = 25°C, IK = 1 to 100mA 100 VIN R3 VOUT IKOFF Cathode Current (nA) 10 VKA = 20V VREF = 0V 1 R1 0.1% VREF SPX2431 0.1 R2 0.1% 0.01 -50 0 50 100 150 TA Ambient Temperature (°C) Figure 19. Off State Leakage Figure 20. Shunt Regulator VOUT = (1+R1/R2)VREF VIN ISINK R2 Q1 VOUT R3 Opto Isolator R1 0.1% Isolated Feedback R3 sets feedback gain, C1 provides feedback compensation SPX2431 R1 0.1% C2 + SPX2431 C1 R2 0.1% VOUTRTN Figure 21. Constant Current, Sink, ISINK = VREF/R1 Figure 22. Reference Amplifier for Isolated Feedback in Off-Line DC-DC Converters © Copyright 2005 Sipex Corporation Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator 6 TYPICAL PERFORMANCE CHARACTERISTICS VIN R5 R4 VIN VOUT R1 0.1% R3 C1 SPX2431 R1 0.1% R2 0.1% R3 VOUT R2 0.1% SPX2431 Q1 Figure 23. Precision High Current Series Regulator VOUT = (1+R1/R2)VREF Figure 24. High Current Shunt Regulator VOUT = (1+R1/R2)VREF VCC R2 VIN R1 VOUT * Resistor values are chosen such that the effect to IREF is negligible. SPX2431 Figure 25. Single Supply Comparator with Temperature Compensated Threshold. VIN Threshold = 2.5V Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 7 PACKAGES: 3 PIN SOT-23 D b 3 B B E1 E SEE VIEW C VIEW A-A 1 e 2 e1 L L1 Gauge Plane Seating Plane Ø VIEW C A A A2 Seating Plane 3 Pin SOT-23 SYMBOL A A1 A2 b c D e e1 E E1 L L1 ø JEDEC TO-236 (AB) Variation MIN NOM MAX 0.89 1.12 0.01 0.1 0.88 0.95 1.02 0.3 0.5 0.08 0.2 2.8 2.9 3.04 0.95 BSC 1.90 BSC 0.95 2.64 1.2 1.3 1.4 0.4 0.5 0.6 0.54 REF 0º 8º A C A1 SIDE VIEW b WITH PLATING c Note: Dimensions in (mm) BASE METAL SECTION B-B Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 8 ORDERING INFORMATION PART NUMBER ACC SPX2431AM ...................... 0.5% SPX2431AM/TR ................ 0.5% SPX2431M ........................ 1.0% SPX2431M/TR .................. 1.0% /TR = Tape and Reel Pack quantity is 2,500 for SOT-23. Available in lead free packaging. To order add "-L" suffix to part number. Example: SPX2431AM/TR = standard; SPX2431AM-L/TR = lead free OUTPUT VOLTAGE PACKAGES ...................... 2.5V ......................... 3 Pin SOT-23 ...................... 2.5V ......................... 3 Pin SOT-23 ...................... 2.5V ......................... 3 Pin SOT-23 ...................... 2.5V ......................... 3 Pin SOT-23 CLICK HERE TO ORDER SAMPLES Corporation ANALOG EXCELLENCE Sipex Corporation Headquarters and Sales Office 22 Linnell Circle Billerica, MA 01821 TEL: (978) 667-8700 FAX: (978) 670-9001 e-mail: sales@sipex.com Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. Date: 1/19/05 SPX2431 Precision Adjustable Shunt Regulator © Copyright 2005 Sipex Corporation 9