1.0 V Precision Low Noise Shunt Voltage Reference ADR510 FEATURES PIN CONFIGURATION Precision 1.000 V voltage reference Ultracompact 3 mm × 3 mm SOT-23 package No external capacitor required Low output noise: 4 μV p-p (0.1 Hz to 10 Hz) Initial accuracy: ±0.35% maximum Temperature coefficient: 70 ppm/°C maximum Operating current range: 100 μA to 10 mA Output impedance: 0.3 Ω maximum Temperature range: −40°C to +85°C ADR510 V+ 1 3 TRIM/NC TOP VIEW (Not to Scale) 03270-001 V– 2 NC = NO CONNECT Figure 1. 3-Lead SOT-23-3 APPLICATIONS Precision data acquisition systems Battery-powered equipment Cellular phone Notebook computer PDA GPS 3 V/5 V, 8-/12-bit data converters Portable medical instruments Industrial process control systems Precision instruments GENERAL DESCRIPTION VS Designed for space critical applications, the ADR510 is a low voltage (1.000 V), precision shunt-mode voltage reference in an ultracompact (3 mm × 3 mm) SOT-23-3 package. The ADR510 features low temperature drift (70 ppm/°C), high accuracy (±0.35%), and ultralow noise (4 μV p-p) performance. A TRIM terminal is available on the ADR510 to provide adjustment of the output voltage over ±0.5% without affecting the temperature coefficient of the device. This feature provides users with the flexibility to trim out any system errors. RBIAS IL VOUT = 1.0V ADR510 IQ COUT (OPTIONAL) RBIAS = VS – VOUT IL + IQ 03270-002 The ADR510 advanced design eliminates the need for an external capacitor, yet it is stable with any capacitive load. The minimum operating current increases from 100 μA to a maximum of 10 mA. This low operating current and ease of use make the ADR510 ideally suited for handheld battery-powered applications. IL + IQ Figure 2. Typical Operating Circuit Table 1. ADR510 Part ADR510A Output Voltage, VOUT 1.000 V Initial Accuracy 3.5 mV 0.35% Temperature Coefficient 70 ppm/°C Rev. B Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2003–2007 Analog Devices, Inc. All rights reserved. ADR510 TABLE OF CONTENTS Features .............................................................................................. 1 Parameter Definitions.......................................................................7 Applications....................................................................................... 1 Temperature Coefficient...............................................................7 Pin Configuration............................................................................. 1 Thermal Hysteresis .......................................................................7 General Description ......................................................................... 1 Applications Information .................................................................8 Revision History ............................................................................... 2 Adjustable Precision Voltage Source...........................................8 Specifications..................................................................................... 3 Output Voltage Trim.....................................................................8 Electrical Characteristics............................................................. 3 Using the ADR510 with Precision Data Converters ................8 Absolute Maximum Ratings............................................................ 4 Precise Negative Voltage Reference ............................................9 Thermal Resistance ...................................................................... 4 Outline Dimensions ....................................................................... 10 ESD Caution.................................................................................. 4 Ordering Guide .......................................................................... 10 Typical Performance Characteristics ............................................. 5 REVISION HISTORY 9/07—Rev. A to Rev. B Changes to Adjustable Precision Voltage Source Section ........... 8 Changes to Figure 11........................................................................ 8 Changes to Figure 12........................................................................ 8 4/07—Rev. 0 to Rev. A Changes to Table 1............................................................................ 1 Changes to Table 3 and Table 4....................................................... 4 Changes to Figure 4, Figure 5, Figure 6, and Figure 7 ................. 5 Changes to Thermal Hysteresis Section ........................................ 7 Changes to Figure 11........................................................................ 8 Changes to Figure 14 and Equation 5 ............................................ 9 Changes to Ordering Guide .......................................................... 10 8/03—Revision 0: Initial Version Rev. B | Page 2 of 12 ADR510 SPECIFICATIONS ELECTRICAL CHARACTERISTICS IIN = 100 μA to 10 mA @ TA = 25°C, unless otherwise noted. Table 2. Parameter Output Voltage 1 Initial Accuracy Temperature Coefficient, A Grade Symbol VOUT VOUTERR VOUTERR% TCVOUT Output Voltage Change vs. IIN Dynamic Output Impedance Minimum Operating Current Voltage Noise Turn-On Settling Time 2 Output Voltage Hysteresis ∆VR (∆VR/∆IR) IIN eN p-p tR VOUT_HYS 1 2 Conditions 0°C < TA < 70°C −40°C < TA < +85°C IIN = 0.1 mA to 10 mA IIN = 1 mA ± 100 μA 0°C < TA < 70°C f = 0.1 Hz to 10 Hz To within 0.1% of output The forward diode voltage characteristic at −1 mA is typically 0.65 V. Measured without a load capacitor. Rev. B | Page 3 of 12 Min 0.9965 −3.5 −0.35 Typ 1.0 100 4 10 50 Max 1.0035 +3.5 +0.35 70 85 3 0.3 Unit V mV % ppm/°C ppm/°C mV Ω μA μV p-p μs ppm ADR510 ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE Table 3. Parameter Reverse Current Forward Current Storage Temperature Range Operating Temperature Range Junction Temperature Range Lead Temperature (Soldering, 60 sec) Rating 25 mA 20 mA −65°C to +150°C −40°C to +85°C −65°C to +150°C 300°C Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. θJA is specified for the worst-case conditions, that is, a device soldered in a circuit board for surface-mount packages. Package power dissipation = (TJMAX − TA)/θJA. Table 4. Thermal Resistance Package Type 3-Lead SOT-23-3 (RT-3) ESD CAUTION Rev. B | Page 4 of 12 θJA 230 θJC 146 Unit °C/W ADR510 TYPICAL PERFORMANCE CHARACTERISTICS 1.002 1.001 1.000 0.999 10 20 30 40 50 60 70 TEMPERATURE (°C) Figure 3. Typical VOUT vs. Temperature TIME (400ns/DIV) Figure 6. Turn-Off Time VIN = 5V/DIV VIN = 5V/DIV VOUT = 500mV/DIV TIME (400ns/DIV) 03270-007 VOUT = 500mV/DIV 03270-004 TIME (1ms/DIV) Figure 4. Turn-On Time Figure 7. Turn-Off Time with 1 μF Input Capacitor ΔIIN = 100µA VIN = 5V/DIV VOUT = 500mV/DIV VOUT = 50mV/DIV TIME (400µs/DIV) TIME (2µs/DIV) Figure 5. Turn-On Time with 1 μF Input Capacitor 03270-008 0 03270-003 0.997 03270-006 VOUT = 500mV/DIV 0.998 03270-005 VOUT (V) VIN = 5V/DIV Figure 8. Output Response to 100 μA Input Current Change Rev. B | Page 5 of 12 ADR510 ΔIIN = 100µA 2µV/DIV TIME (400ms/DIV) Figure 9. Output Response to 100 μA Input Current Change with 1 μF Capacitor Figure 10. 1 Hz to 10 Hz Noise Rev. B | Page 6 of 12 03270-010 TIME (2µs/DIV) 03270-009 VOUT = 50mV/DIV ADR510 PARAMETER DEFINITIONS TEMPERATURE COEFFICIENT THERMAL HYSTERESIS This is the change of output voltage with respect to the operating temperature changes, normalized by the output voltage at 25°C. This parameter is expressed in parts per million/degrees Celsius (ppm/°C) and can be determined with the following equation: Thermal hysteresis is the change of output voltage after the device is cycled through the temperature from 25°C to 0°C to 85°C and back to 25°C. TCVOUT [ppm/ °C] = VOUT (T2) − VOUT (T1) VOUT (25°C ) × (T2 − T1) where: VOUT(25°C) is the output voltage at 25°C. VOUT(T1) is the output voltage at Temperature 1. VOUT(T2) is the output voltage at Temperature 2. × 10 6 VOUT _ HYS = VOUT (25°C) − VOUT _ TC VOUT _ HYS [ppm] = (1) VOUT ( 25°C ) − VOUT _ TC VOUT (25°C ) × 10 6 (2) where: VOUT(25°C) is the output voltage at 25°C. VOUT_TC is the output voltage at 25°C after temperature cycle at +25°C to −40°C to +85°C and back to +25°C. Rev. B | Page 7 of 12 ADR510 APPLICATIONS INFORMATION The ADR510 is a 1.0 V precision shunt voltage reference designed to operate without an external output capacitor between the positive terminal and the negative terminal for stability. An external capacitor can be used for additional filtering of the supply. OUTPUT VOLTAGE TRIM • RBIAS must be small enough to supply the minimum IQ current to the ADR510 even when the supply voltage is at minimum value and the load current is at maximum value. RBIAS also needs to be large enough so that IQ does not exceed 10 mA when the supply voltage is at its maximum value and the load current is at its minimum value. Given these conditions, RBIAS is determined by the supply voltage (VS), the load and operating current (IL and IQ) of the ADR510, and the ADR510 output voltage. R BIAS = VS − VOUT (3) I L + IQ ADJUSTABLE PRECISION VOLTAGE SOURCE The ADR510, combined with a precision low input bias op amp such as the AD860x, can be used to output a precise adjustable voltage. Figure 11 illustrates implementation of this application using the ADR510. RBIAS VOUT = 1 + Figure 12. Output Voltage Trim USING THE ADR510 WITH PRECISION DATA CONVERTERS The compact ADR510 and its low minimum operating current requirement make it ideal for use in battery-powered portable instruments, such as the AD7533 CMOS multiplying DAC, that use precision data converters. Figure 13 shows the ADR510 serving as an external reference to the AD7533, a CMOS multiplying DAC. Such a DAC requires a negative voltage input in order to provide a positive output range. In this application, the ADR510 is supplying a −1.0 V reference to the REF input of the AD7533. 1.0V VOUT = (1 + R2/R1) 03270-011 R2 C2 (OPTIONAL) – –VDD RBIAS R1 ADR510 R2 VCC ADR510 0 + 9 LSB MSB VDD 1 AD7533 1 An additional capacitor in parallel with R2 can be added to filter out high frequency noise. The value of C2 is dependent on the value of R2. AD860x POT 10kΩ R1 470kΩ 2 (4) R1 3 ADR510 Output of the op amp, VOUT, is determined by the gain of the circuit, which is completely dependent on the R2 and R1 resistors. R2 VOUT 1 Figure 11. Adjustable Precision Voltage Source Rev. B | Page 8 of 12 GN 3 2 1 15 + VOUT = 0V TO 1.0V – 03270-013 • VCC 03270-012 As with all shunt voltage references, an external bias resistor (RBIAS) is required between the supply voltage and the ADR510 (see Figure 2). RBIAS sets the current that is required to pass through the load (IL) and the ADR510 (IQ). The load and the supply voltage can vary, thus RBIAS is chosen based on the following conditions: Using a mechanical or digital potentiometer, the output voltage of the ADR510 can be trimmed ±0.5%. The circuit in Figure 12 illustrates how the output voltage can be trimmed using a 10 kΩ potentiometer. Note that trimming using other resistor values may not produce an accurate output from the ADR510. Figure 13. ADR510 as a Reference for a 10-Bit CMOS DAC (AD7533) ADR510 PRECISE NEGATIVE VOLTAGE REFERENCE The ADR510 is suitable for use in applications where a precise negative voltage reference is desired, including the application detailed in Figure 13. Figure 14 shows the ADR510 configured to provide an output of −1.0 V. ADR510 Because the ADR510 characteristics resemble those of a Zener diode, the cathode shown in Figure 14 is 1.0 V higher with respect to the anode (V+ with respect to V− on the ADR510 package). Because the cathode of the ADR510 is tied to ground, the anode must be −1.0 V. R1 in Figure 14 should be chosen so that 100 μA to 10 mA is provided to properly bias the ADR510. + R1 = – –1.0V –VDD I 03270-014 R1 −1 − (−VDD ) I (5) The R1 resistor should be chosen so that power dissipation is at a minimum. An ideal resistor value can be determined through manipulation of Equation 5. Figure 14. Precise −1.0 V Reference Configuration Rev. B | Page 9 of 12 ADR510 OUTLINE DIMENSIONS 3.04 2.90 2.80 1.40 1.30 1.20 3 1 2.64 2.10 2 PIN 1 0.95 BSC 1.90 BSC 1.12 0.89 0.10 0.01 0.50 0.30 SEATING PLANE 0.20 0.08 0.60 0.50 0.40 COMPLIANT TO JEDEC STANDARDS TO-236-AB Figure 15. 3-Lead Small Outline Transistor Package [SOT-23-3] (RT-3) Dimensions shown in millimeters ORDERING GUIDE Model ADR510ART-REEL7 ADR510ART-R2 ADR510ARTZ-REEL71 ADR510ARTZ-R21 1 Output Voltage (VOUT) 1.0 V 1.0 V 1.0 V 1.0 V Initial Accuracy 3.5 mV 0.35% 3.5 mV 0.35% 3.5 mV 0.35% 3.5 mV 0.35% Temperature Coefficient 70 ppm/°C 70 ppm/°C 70 ppm/°C 70 ppm/°C Temperature Range −40°C to +85°C −40°C to +85°C −40°C to +85°C −40°C to +85°C Z = RoHS Compliant Part. # denotes lead free, may be top or bottom marked. Rev. B | Page 10 of 12 Package Description 3-Lead SOT-23-3 3-Lead SOT-23-3 3-Lead SOT-23-3 3-Lead SOT-23-3 Package Option RT-3 RT-3 RT-3 RT-3 Ordering Quantity 3,000 250 3,000 250 Branding RAA RAA RAA# RAA# ADR510 NOTES Rev. B | Page 11 of 12 ADR510 NOTES ©2003–2007 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D03270-0-9/07(B) Rev. B | Page 12 of 12