AS431C Precision Adjustable Shunt Regulator FEATURES • • • • • • APPLICATIONS • • • • • • • Wide Operating Current…………………….1mA to 150mA Extended Termperature Range……………………… 105°°C Low Temperature Coeffecient 30 ppm/°C Offered in TO-92, SOT-89 & SOT-23-5 Packages Improved Replacement in Performance for TL431 Low Cost Solution Battery Operating Equipments Adjustable Supplies Switching Power Supplies Error Amplifiers Single Supply Amplifier Monitors / VCR / TV Personal Computers PRODUCT DESCRIPTION The AS431C is a 3-Terminal Adjustable Shunt Voltage Regulator providing a highly accurate bandgap reference. AS431C acts as an open-loop error amplifier with a 2.5V temperature compensation reference. The AS431C thermal stability, wide operating current (150mA) and temperature range (105°C) makes it suitable for all variety of applications that are looking for a low cost solution with high performance. The output voltage may be adjusted to any value between VREF and 36V with 2 external resistors. The AS431C is operating in full industrial temperature range of 0°C to 105°C. The AS431C is available in TO-92, SOT-23-5 and SOT-89 packages. PIN CONFIGURATION SOT-23-5 (M5) REF ANODE 5 4 1 3 2 N/C N/C 2 CATHODE Top View 1 REF 2 3 ANODE CATHODE Top View REF ANODE Temperature Range 0°C to 105°C 0°C to 105°C 0°C to 105°C Package Type TO-92 SOT-89 SOT-23-5 CATHODE Bottom View CATHODE (K) ORDERING INFORMATION Part Number AS431CN AS431CM1 AS431CM5 3 AS431C AS431C 1 TO-92 (N) SOT-89 (M1) REFERENCE (R) + - 2.5V ANODE (A) Rev. 10/5/00 AS431C 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 SOT-23 SOT-89 Junction Temperature Storage Temperature Lead Temperature (Soldering 10 sec.) Symbol VKA IAK IKA IREF PD TJ TSTG TL Rating 37 1 150 10 Units V A mA mA 775 200 1000 150 - 65 to +150 30 mW mW mW °C °C °C 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 20 10 TYPICAL THERMAL RESISTANCE Unit V mA Package Type TO-92 SOT-23 SOT-89 θJA 160°C/W 575°C/W 110°C/W θJC 80°C/W 150°C/W 8°C/W Typical Derating 6.3 mW/°C 1.7 mW/°C 9.1 mW/°C ELECTRICAL CHARACTERISTICS at 25°C Ik @ 10mA Vk=Vref , unless otherwise specified. Parameter Reference Voltage Ratio of Change in VREF to Cathode Voltage Reference Input Current IREF Temp Deviation Min IK for Regulation Off State Leakage Dynamic Output Impedance Symbol VREF ∆ VREF ∆VK IREF ∆IREF IK(MIN) IK(OFF) ZKA Test Conditions TA = 25°C TC = 1 VREF to 10V 10V to 36V TC = 2 TC = 2 Over Temp. TC = 2 TC = 1 VREF = 0V, VKA = 36V TC=3 TC = 1 Min 2.445 -2.7 -2 AS431C Typ 2.495 -1.0 -0.4 0.7 0.4 0.4 0.04 0.15 Unit Max 2.545 V mV/V 0.3 4 1.2 1 1 µA µA mA µA 0.5 Ω TC = Test Circuit Rev. 10/5/00 AS431C 0 mV % ppm *CALCULATING AVERAGE TEMPERATURE COEFFICEINT (TC) 0 0 ∆VREF TC in mV/°C = ∆T -10 5000 TC in mV/°C = 0.5 0 15 30 45 60 75 90 TC in ppm/°C = 105 ∆VREF (mV) ∆TA ( ∆VREF ∆VREF at 25°C ∆TA ( ) ∆VREF ∆VREF at 25°C ∆TA x 100 ) x 106 0.07 mV/°C 0.003 %/°C 27 ppm/°C TEST CIRCUITS VIN IREF VKA = VREF IK VIN VKA IK R 1 (VREF) VIN VKA IK (OFF) IREF R 2 1G-38 TEST CIRCUIT For VKA= VREF 1G-40 1G-39 TEST CIRCUIT For VKA > VREF TEST CIRCUIT For IROFF Rev. 10/5/00 AS431C TYPICAL PERFORMANCE CURVES Low Current Operating Characteristics High Current Operating Characteristics 900 150 VKA = VREF Temperature Range: - 0 °C to 125 °C 700 100 600 75 500 400 105 °C 300 VKA = VREF Temperature Range: - 0°C to 125 °C 125 IK - Cathode Current (mA) µA) IK - Cathode Current (µ 800 25 °C 200 50 25 0 -25 -0°C 100 -50 0 -75 -100 -100 -2 -1 -200 -1.0 0 1.0 2.0 0 1 2 3 VKA - Cathode Voltage (V) 3.0 Figure 3 VKA - Cathode Voltage (V) Figure 2 Off State Leakage Reference Voltage vs. Ambient Temperature 100 2.53 VKA = VREF IK = 10 mA 2.52 10 2.51 VREF - Reference Voltage (V) IZ off - Off State Cathode Current (nA) VKA = 36V VREF = 0V 1 0.1 2.50 VREF = 2.500 V at 25 °C 2.49 2.48 2.47 2.46 0.01 2.45 -60 -30 0 30 60 90 120 -60 -30 0 30 60 TA - Ambient Temperature ( °C) TA - Ambient Temperature ( °C) Figure 4 Figure 5 90 120 Rev. 10/5/00 AS431C TYPICAL PERFORMANCE CURVES Reference Input Current Reference Voltage Line Regulation 0 3.0 R1 = 10 kΩ R2 = ∞ IK = 10 mA -10 VKA - Cathode Voltage (V) ( A) IREF - Reference Input Current µ 2.5 2.0 1.5 0 °C -20 25 °C 75 °C -30 105 °C -40 1.0 -50 0.5 0 3 6 9 12 15 18 21 24 27 30 VKA - Cathode Voltage (V) 0 -60 -30 0 30 60 90 Figure 7 120 TA - Ambient Temperature ( °C) Figure 6 Noise Voltage Low Frequency Dynamic Output Impedance 70 0.150 VKA = VREF IKA = 1 to 100 mA f < 1 kHz 0.125 Ω) ZKA - Dynamic Impedance (Ω 60 √Hz Noise Voltage nV/√ 50 40 30 0.100 0.075 0.050 20 0.025 10 0.0 -60 -30 0 30 60 90 120 TA - Free Air Temperature 0 10 100 1k 10 k 100 k Figure 9 f - Frequency (Hz) Figure 8 Rev. 10/5/00 AS431C TYPICAL PERFORMANCE CURVES Dynamic Output Impedance 100 TA = 25 °C IK = 1 to 100 mA Ω) ZKA - Dynamic Impedance (Ω 10 1.0 0.1 0.01 1k 10 k 100 k 1M 10 M f - Frequency (Hz) Figure 10 Small Signal Voltage Gain vs. Frequency 70 Temperature Range: -0°C to 125 °C 60 AV - Small Signal Voltage Gain (dB) IK = 10 mA 50 OUT 40 15 k IK 230 Ω 9 µF 30 8.25 k 20 GND 10 0 1k 10 k 100 k 1M 10 M f - Frequency (Hz) Figure 11 Rev. 10/5/00 AS431C TYPICAL PERFORMANCE CURVES Pulse Response 6 INPUT 5 INPUT MONITOR 220 Ω Input and Output Voltages (V) 4 OUT 3 OUTPUT 50 Ω 2 fP = 100 kHz 1 GND 0 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 µs) t - Time (µ Figure 12 Stability Boundary Conditions 100 A: B: C: D: 90 VKA VKA VKA VKA = VREF = 5V at IK = 10 mA = 10V at IK = 10 mA = 15V at IK = 10 mA 80 IK - Cathode Current (mA) 70 C 150 Ω 60 IK 50 40 STABILITY REGION CL 30 10 k A 20 10 B TA = 25 °C D 0 10 0 10 1 10 2 10 3 10 4 10 5 10 6 10 7 CL - Load Capacitance (pF) Figure 13 Rev. 10/5/00