AS2431CASA

SEMICONDUCTOR AS2431Reference Precision Adjustable Shunt Description The AS2431 is a three-terminal adjustable shunt regulator providing a highly accurate bandgap reference. The adjustable shunt regulator is ideal for a wide variety of linear applications that can be implemented using external components to obtain adjustable currents and voltages. In the standard shunt configuration, the combination of low temperature coefficient (TC), sharp turn-on characteristics, low output impedance and programmable output voltage make this precision reference an excellent error amplifier. The AS2431 is a direct replacement for the AS431 in low voltage, low current applications. It is also available in the very small footprint SOT23. Features • • • • • • Temperature-compensated: 15 ppm/°C Trimmed bandgap reference Internal amplifier with 100 mA capability Multiple temperature ranges Low frequency dynamic output impedance: < 450 mΩ Low output noise Pin Configuration – Top View TO-92 (LP) CATHODE CATHODE ANODE ANODE REFERENCE ANODE N/C 2 3 4 1 8L SOIC (8D) 8 7 6 5 REFERENCE ANODE ANODE N/C SOT-89 (S) 3L SOT-23 (3VS) CATHODE CATHODE ANODE REFERENCE ANODE REFERENCE Ordering Information AS2431 A C 8D N Circuit Type: Precision Adjustable Shunt Regulator Bandgap Tolerance: A = ±0.25% C = ±0.5% D = ±1.0% E = ±2.0% Temperature Range: A = 0°C to 70°C B = 0°C to 105°C C = –40°C to +85°C F = –55°C to +125°C Packaging Option: A = Ammo Pack B = Bulk T = Tube M = Tape and Reel (7" Reel Dia. SOT-23 Only) N = Tape and Reel (13" Reel Dia) Package Style: 8D = 8 Pin, Plastic SOIC LP = TO-92 S = SOT-89 3VS = 3 Pin, SOT-23 www.ptcc.com.tw 17 AS2431 Functional Block Diagram Precision Adjustable Shunt Reference CATHODE (K) REFERENCE (R) + – 2.5 V ANODE (A) Absolute Maximum Ratings Parameter Cathode-Anode Reverse Breakdown Anode-Cathode Forward Current Operating Cathode Current Reference Input Current Continuous Power Dissipation at 25°C TO-92 8L SOIC SOT-89 3L SOT-23 Junction Temperature Storage Temperature Lead Temp, Soldering 10 Seconds TJ TSTG TL Symbol VKA IAK IKA IREF PD 775 750 1000 200 150 –65 to 150 300 mW mW mW mW °C °C °C Rating 18 1 100 1 Units V A mA mA Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability. Recommended Conditions Parameter Cathode Voltage Cathode Current Symbol VKA IK Rating VREF to 18 10 Unit V mA Typical Thermal Resistances Package TO-92 SOIC SOT-89 θJA 160°C/W 175°C/W 110°C/W θJC 80°C/W 45°C/W 8°C/W 150°C/W Typical Derating 6.3 mW/°C 5.7 mW/°C 9.1 mW/°C 1.7 mW/°C SOT-23/5L 575°C/W www.ptcc.com.tw 18 AS2431 Average Temperature Coefficient ppm mV Precision Adjustable Shunt Reference 0 0 0 ∆VREF ∆T –10 • TC in mV/°C = ∆VREF (mV) ∆TA ∆VREF % 5000 0.5 • TC in %/°C = VREF at 25°C ∆TA ∆VREF X 100 –20 0 15 30 45 60 75 Temperature (°C) 90 105 • TC in ppm/°C = VREF at 25°C ∆TA X 106 0.07 mV/°C 0.003%/°C 27 ppm/°C Test Circuits VIN VKA = VREF VIN VKA VIN VKA IREF IK IK R1 IREF (VREF) R2 IK (OFF) Figure 1a. Test Circuit 1 Figure 1b. Test Circuit 2 Figure 1c. Test Circuit 3 www.ptcc.com.tw 20 Precision Adjustable Shunt Reference Typical Performance Curves AS2431 Low Current Operating Characteristics 900 800 700 IK – Cathode Current (mA) 600 IK – Cathode Current (µA) 500 400 300 200 100 0 –100 –200 –1.0 0 1.0 2.0 3.0 125°C 25°C –55°C VKA = VREF Temperature Range: –55 to 125°C 150 125 100 75 50 25 0 –25 –50 –75 –100 –2 High Current Operating Characteristics VKA = VREF Temperature Range: –55 to 125°C –1 0 1 2 3 VKA – Cathode Voltage (V) VKA – Cathode Voltage (V) Figure 2 Figure 3 Off State Leakage 100 VKA = 18 V VREF = 0 V IZ off – Off State Cathode Current (nA) VREF – Reference Voltage (V) 10 3.53 2.52 2.51 2.50 2.49 2.48 2.47 2.46 0.01 –60 2.45 –60 Reference Voltage vs Ambient Temperature VKA = VREF IK = 10 mA VREF = 2.500 V at 25°C 1 0.1 –30 0 30 60 90 120 –30 0 30 60 90 120 TA – Ambient Temperature (°C) TA – Ambient Temperature (°C) Figure 4 Figure 5 www.ptcc.com.tw 21 AS2431 Typical Performance Curves Precision Adjustable Shunt Reference Reference Input Current 3.0 R1 = 10 kΩ R2 = ∞ IK =10 mA 0 Reference Voltage Line Regulation –30°C ∆VREF – Change in Reference Voltage (mV) –5 2.5 IREF – Reference Input Current (µA) 2.0 –10 25°C –15 75°C –20 IK = 10 mA Temperature Range: –55 to 125°C –25 0 3 6 9 12 15 125°C 1.5 1.0 0.5 0 –60 –30 0 30 60 90 120 18 TA – Ambient Temperature (°C) VKA – Cathode Voltage (V) Figure 6 Figure 7 Noise Voltage 70 60 VKA = VREF IK = 10 mA TA = 25°C ZKA – Dynamic Impedance (Ω) 0.150 Low Frequency Dynamic Output Impedance VKA = VREF IKA = 1 to 100 mA f ≤ 1 kHz 0.125 50 Noise Voltage nV/√Hz 0.100 40 30 0.075 20 0.050 10 0 10 100 1k f – Frequency (Hz) 10 k 100 k 0.025 0.0 –60 –30 0 30 60 90 120 TA – Free Air Temperature Figure 8 Figure 9 www.ptcc.com.tw 22 Precision Adjustable Shunt Reference Typical Performance Curves AS2431 Dynamic Output Impedance 100 TA = 25°C IK = 1 to 100 mA ZKA – Dynamic Impedance (Ω) 10 1.0 0.1 0.01 1k 10 k 100 k f – Frequency (Hz) 1M 10 M Figure 10 Small Signal Voltage Gain vs. Frequency 70 Temperature Range: –55 to 125°C 60 AV – Small Signal Voltage Gain (dB) IK = 10 mA 50 40 30 8.25 k GND 20 10 0 1k 9 µF 15 k IK OUT 230 Ω 10 k 100 k f – Frequency (Hz) 1M 10 M Figure 11 www.ptcc.com.tw 23 AS2431 Typical Performance Curves Precision Adjustable Shunt Reference Pulse Response 6 Input 5 Input and Output Votages (V) 4 3 2 1 GND 0 –1 0 1 2 3 4 5678 t – Time (ms) 9 10 11 12 Output fP = 100 kHz INPUT MONITOR 220 Ω OUT 50 Ω Figure 12 Stability Boundary Conditions 100 90 80 IK – Cathode Current (mA) 70 60 50 40 30 20 10 0 100 TA = 25°C B D 101 102 103 104 105 106 107 Stability Region CL A 10 K C IK A: VKA = VREF B: VKA = 5 V at IK = 10 mA C: VKA = 10 V at IK = 10 mA D: VKA = 15 V at IK = 10 mA 150 Ω CL – Load Capacitance (pF) Figure 13 www.ptcc.com.tw 24