AS1004 Micropower Voltage Reference Features Description • • The AS1004 is a two-terminal precision band-gap voltage reference with a low turn-on current of 10 µA. Low voltage reference 10 µA turn-on current for AS1004-1.2 • 20 µA turn-on current for AS1004-2.5 • ± 4 mV (0.3 %) initial accuracy for AS1004-1.2 • ± 20 mV (0.8 %) initial accuracy for AS1004-2.5 • Guaranteed operation to 20 mA. Over three orders of magnitude of operating current! • Temperature performance guaranteed • Very low dynamic impedance Pin Configuration — Emulating a 1.235 V zener diode, the AS1004 operates more than three orders of magnitude of output current with minute output impedance and guaranteed stability. With an initial tolerance of ± 4 mV and guaranteed temperature performance, it is ideal for precision instrumentation, especially in low power applications. Being a low-voltage reference, the AS1004 is also well-suited as a reference for low-voltage power supply applications, especially in power supplies intended for low-voltage logic systems, laptop computers and other portable or battery operated equipment. The AS1004 is pin-for-pin compatible with the LT1004 and the LM385 and offers improved specifications over both the LM385 and the MP5010. It is also available as a 2.5 V reference with a guaranteed start-up current of 20 µA. Top view TO-92 (LP) SOIC (D) SOT-89 (S) N/C 1 8 CATHODE N/C 2 7 N/C N/C 3 6 CATHODE ANODE 4 5 ANODE N/C ANODE ANODE CATHODE N/C CATHODE Ordering Information Description Temperature Range Order Codes TO-92 0 to 70° C AS1004-1.2LP AS1004-2.5LP 8-Pin Plastic SOIC 0 to 70° C AS1004-1.2D AS1004-2.5D SOT-89 0 to 70° C AS1004-1.2S AS1004-2.5S © ASTEC Semiconductor 29 Micropower Voltage Reference AS1004 Simplified Schematic K R2 Q13 Q4 Q12 Q3 C2 R10 Q7 R4 Q11 C1 C3 R11 Q5 Q1 Q10 R12 Q9 Q8 Q6 R6 R7 Q14 A Absolute Maximum Ratings Parameter Symbol Rating Units Reverse Breakdown Current IZ 30 mA Forward Current IF 30 mA Continuous Power Dissipation at 25° C PD TO-92 775 mW 8LSOIC 750 mW SOT-89 1000 mW TJ 150 °C TSTG – 65 to 150 °C TL 300 °C Maximum Junction Temp Storage Temperature Lead Temperature, Soldering 10 Seconds Typical Thermal Resistances Recommended Conditions Parameter Cathode Current ASTEC Semiconductor θJA θJC Typical Derating TO-92 160° C/W 80° C/W 6.3 mW/°C 8L SOIC 175° C/W 45° C/W 5.7 mW/°C SOT-89 110° C/W 8° C/W 9.1 mW/°C Symbol Rating Unit Package IZ 100 µA 30 Micropower Voltage Reference AS1004 Electrical Characteristics Electrical Characteristics are guaranteed over full junction temperature range (0 to 70° C). Ambient temperature must be derated based on power dissipation and package thermal characteristics. Test Condition Reverse Breakdown Voltage VZ IZ = 100 µA, TJ = 25° C 1.231 1.235 1.239 2.480 2.500 2.520 V 0° C ≤ TA ≤ 70° C 1.225 1.235 1.245 2.470 2.500 2.530 V ∆VZ /∆T Minimum Operating Current IZ (min) Reverse Breakdown Voltage Change With Current ∆VZ /∆IZ Imin ≤ IZ ≤ 20 mA Reverse Dynamic Impedance ZZ Wide Band Noise en ∆VZ /∆T Long Term Stability Min AS1004-2.5 Typ Max Symbol Average Temperature Coefficient Min AS1004-1.2 Typ Max Parameter 20 60 Unit ppm/°C 4 10 12 20 µA Imin ≤ IZ ≤ 1 mA 0.5 1 0.5 1 mV Over Temperature 0.5 1.5 0.5 1.5 mV 1 mA ≤ IZ ≤ 20 mA 6.5 10 6.5 10 mV Over Temperature 6.5 20 6.5 20 mV IZ = 100 mA, f = 25 Hz 0.2 0.6 0.8 0.9 Ω Over Temperature 1 1.5 1.5 Ω IZ = 100 µA 10 Hz ≤ f ≤ 10 KHz 60 60 µV IZ = 100 µA TA = 25° C ± 0.1° C 20 60 ppm/kH Typical Performance Curves AS1004-1.2 Reference Voltage vs. Ambient Temperature Calculating Average Temperature Coefficient for the AS1004-1.2 Reference 0 mV IZ = 100 µA 0 ∆VREF ∆T V Z – Reference Voltage (V) 0 % ppm 1.245 -5 5000 0.5 -10 0 10 20 30 40 50 60 70 Temperature (°C) 1.240 1.235 1.230 0.025 mV/ °C 1.225 0.002 %/ °C 20 ppm/ °C Average Temperature Coefficient = ∆VREF ∆T –55 –35 Figure 1 ASTEC Semiconductor –15 5 25 45 65 85 TA – Ambient Temperature (°C) Figure 2 31 105 125 Micropower Voltage Reference AS1004 Typical Performance Curves 0 0 AS1004-2.5 Reference Voltage versus Ambient Temperature 2.520 mV % ppm Calculating Average Temperature Coefficient for the AS1004-2.5 Reference IZ = 100 µA 0 ∆VREF V Z – Reference Voltage (V) ∆T -5 5000 0.5 -10 0 10 20 30 40 50 60 70 Temperature (°C) 2.510 2.500 2.490 0.046 mV/ °C 0.004 %/ °C 37 ppm/ °C Average Temperature Coefficient = 2.480 ∆VREF ∆T –55 –35 Figure 4 AS1004-1.2 Reverse Operating Characteristics AS1004-2.5 Reverse Operating Characteristics 125 100 TA = –55° C to 125° C TA = –55° C to 125° C IR – Reverse Current (µA) IR – Reverse Current (µA) 105 Figure 3 100 10 1 0.1 –15 5 25 45 65 85 TA – Ambient Temperature (°C) 0 0.2 0.4 0.8 0.6 1 VR – Reverse Voltage (V) 1.2 1 0.1 1.4 Figure 5 ASTEC Semiconductor 10 0 0.5 1.0 1.5 2.0 VR – Reverse Voltage (V) Figure 6 32 2.5 3.0 Micropower Voltage Reference AS1004 Typical Performance Curves AS1004-1.2 Change in Reference Voltage versus Reverse Current AS1004-2.5 Change in Reference Voltage versus Reverse Current 16 16 TA = –55° C to 125° C ∆VZ – Change In Reference Voltage (mA) ∆VZ – Change In Reference Voltage (mA) TA = –55° C to 125° C 12 8 4 0 –4 0.01 0.1 1 10 IR – Reverse Current (mA) 12 8 4 0 –4 0.01 100 0.1 1 10 IR – Reverse Current (mA) Figure 7 Figure 8 AS1004-1.2 Transient Response AS1004-2.5 Transient Response 1.5 3 OUTPUT 36 kΩ VI 0.5 VO 0 5 INPUT 0 50 36 kΩ VI VO 1 0 5 INPUT 100 500 0 600 t – Time (µs) 0 50 t – Time (µs) Figure 10 Figure 9 ASTEC Semiconductor OUTPUT 2 Input and Output Voltage (V) Input and Output Voltage (V) 1 0 100 33 100 500 600 Micropower Voltage Reference AS1004 Typical Performance Curves AS1004-1.2 Reverse Dynamic Impedance AS1004-2.5 Reverse Dynamic Impedance 10 k 10 k tZ = 100 µA TA = 25° C 1k ZZ – Reference Impedance (Ω) ZZ – Reference Impedance (Ω) tZ = 100 µA TA = 25° C 100 10 1 0.1 0.01 0.1 1 10 f = Frequency (kHz) 100 1k 100 10 1 0.1 0.01 1k Figure 11 100 1k Low Frequency Reverse Dynamic Impedance 100 1.2 TA = –55° C to 125° C f = 25 Hz ZZ – Reference Impedance (Ω) TA = 25° C V F – Forward Voltage (V) 1 10 f = Frequency (kHz) Figure 12 Forward Characteristics 0.8 0.4 0 0.01 0.1 0.1 1 10 IF = Forward Current (mA) 1 0.1 0.01 100 Figure 13 ASTEC Semiconductor 10 0.1 1 10 IZ – Reverse Current (mA) Figure 14 34 100 Micropower Voltage Reference AS1004 Typical Applications 2.5V Reference 1.235V Reference Low Noise Reference VIN VIN VIN 3k 100 k 100 k 22 Ω OUT OUT AS1004-1.2 OUT AS1004-2.5 AS1004-2.5 Figure 15 Figure 16 Variable Output Regulator V Figure 17 High Stability 5V Regulator VIN ≥ 8 V IN VIN LM317 VOUT VIN OUT ADJ LM338 VOUT 5 V OUT ADJ 200 Ω 0.1 µF 50 µF 976 Ω, 1% + + 10 µF 22 µF 5k AS1004-2.5 AS1004-2.5 R≤ 324 Ω, 1% V - – 1V 0.015 mA V- Figure 18 Figure 19 Lead Acid Low Battery Detector Micropower 10V Reference VIN = 12 V to 20 V LO = Battery Low 86.7 k 500 k 1M + 12 V 3 – 500 k LM4250 2 – 4 150 pF AS1004-1.2 6 8 22 M 150 pF AS1004-1.2 Figure 20 ASTEC Semiconductor 7 + 500 k Figure 21 35 3.5 M Micropower Voltage Reference AS1004 Notes ASTEC Semiconductor 36