Precision VOLTAGE REFERENCE

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1 Precision VOLTAGE REFEREE FEATURES 10V ±0.00PUT VERY LOW DRIFT:.ppm/ C max EXCELLENT STABILITY: ppm/1000hr typ EXCELLENT LINE REGULATION: 1ppm/V max EXCELLENT LOAD REGULATION: 10ppm/mA max LOW NOISE: µvp-p typ, 0.1Hz to 10Hz WIDE SUPPLY RANGE: 11.VDC to VDC LOW QUIESCENT CURRENT: 1.mA max PACKAGE OPTIONS: HERMETIC TO-99, PLASTIC DIP, SOIC APPLICATIONS PRECISION-CALIBRATED VOLTAGE STANDARD D/A AND A/D CONVERTER REFEREE PRECISION CURRENT REFEREE ACCURATE COMPARATOR THRESHOLD REFEREE DIGITAL VOLTMETERS TEST EQUIPMENT PC-BASED INSTRUMENTATION DESCRIPTION Trim The is a precision 10V voltage reference. The drift is laser-trimmed to.ppm/ C max (CM grade) over the industrial temperature range and ppm/ C max (SM grade) over the military temperature range. The achieves its precision without a heater. This results in low power, fast warm-up, excellent stability, and low noise. The output voltage is extremely insensitive to both line and load variations and can be externally adjusted with minimal effect on drift and stability. Single supply operation from 11.V to V and excellent overall specifications make the an ideal choice for demanding instrumentation and system reference applications. R R 1 0k Ω R R k Ω 1k Ω R DZ 1 8 7k Ω Noise Common Reduction A1 8k Ω R k Ω International Airport Industrial Park Mailing Address: PO Box 1100, Tucson, AZ 87 Street Address: 70 S. Tucson Blvd., Tucson, AZ 870 Tel: (0) Twx: Internet: FAXLine: (800) 8-1 (US/Canada Only) Cable: BBRCORP Telex: 0-91 FAX: (0) Immediate Product Info: (800) Burr-Brown Corporation PDS-900E Printed in U.S.A. October, 199

2 SPECIFICATIONS ELECTRICAL At T A = C and V S = 1V power supply, unless otherwise noted. A, R B, S C, M PARAMETER CONDITIONS MIN TYP MAX MIN TYP MAX MIN TYP MAX UNITS OUTPUT VOLTAGE Initial T A = C V vs Temperature (1) 10. ppm/ C vs Supply (Line Regulation) V S = 11.V to V 1 1 ppm/v vs Output Current (Load Regulation) I L = 0mA to 10mA ppm/ma I L = 0mA to ma ppm/ma vs Time T A = M Package ppm/1000hr P, U Packages () 0 ppm/1000hr Trim Range () ± % Capacitive Load, max 1000 pf NOISE (0.1Hz to 10Hz) µvp-p OUTPUT CURRENT 10, ma INPUT VOLTAGE RANGE 11. V QUIESCENT CURRENT (I OUT = 0) 1. ma WARM-UP TIME () (To 0.1%) 1 µs TEMPERATURE RANGE Specification A, B, C 8 C R, S 1 C Specifications same as A/R. NOTES: (1) The box method is used to specify output voltage drift vs temperature. See the Discussion of Performance section. () Typically ppm/1000hrs after 18hr powered stabilization. () Trimming the offset voltage affects drift slightly. See Installation and Operating Instructions for details. () With noise reduction pin floating. See Typical Performance Curves for details. The information provided herein is believed to be reliable; however, BURR-BROWN assumes no responsibility for inaccuracies or omissions. BURR-BROWN assumes no responsibility for the use of this information, and all use of such information shall be entirely at the user s own risk. Prices and specifications are subject to change without notice. No patent rights or licenses to any of the circuits described herein are implied or granted to any third party. BURR-BROWN does not authorize or warrant any BURR-BROWN product for use in life support devices and/or systems.

3 ORDERING INFORMATION TEMPERATURE MAX INITIAL MAX DRIFT PRODUCT PACKAGE RANGE ERROR (mv) (ppm/ C) AU 8-Pin SOIC C to 8 C ±10 ±10 AP 8-Pin Plastic DIP C to 8 C ±10 ±10 BP 8-Pin Plastic DIP C to 8 C ± ± AM Metal TO-99 C to 8 C ±10 ±10 BM Metal TO-99 C to 8 C ± ± CM Metal TO-99 C to 8 C ±. ±. RM Metal TO-99 C to 1 C ±10 ±10 SM Metal TO-99 C to 1 C ± ± PIN CONFIGURATIONS ABSOLUTE MAXIMUM RATINGS Top View Com DIP/SOIC Noise Reduction Trim Input Voltage... 0V Operating Temperature P,U... C to 8 C M... C to 1 C Storage Temperature Range P,U... 0 C to 8 C M... C to 10 C Lead Temperature (soldering, 10s) C (SOIC, s)... 0 C Short-Circuit Protection to Common or... Continuous Top View Noise Reduction Common Trim TO-99 ELECTROSTATIC DISCHARGE SENSITIVITY This integrated circuit can be damaged by ESD. Burr-Brown recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. PACKAGE INFORMATION PACKAGE DRAWING PRODUCT PACKAGE NUMBER (1) AU 8-Pin SOIC 18 AP 8-Pin Plastic DIP 00 BP 8-Pin Plastic DIP 00 AM Metal-TO BM Metal-TO CM Metal-TO RM Metal-TO SM Metal-TO NOTE: (1) For detailed drawing and dimension table, please see end of data sheet, or Appendix C of Burr-Brown IC Data Book.

vs FREQUEY 1. LOAD REGULATION Power Supply Rejection (db) 10 110 100 90 80 70 Output Voltage Change (mv) 1.0 0. 0 0. 1.0 0 1 100 1k 10k Frequency (Hz) 1.

4 TYPICAL PERFORMAE CURVES At T A = C, V S = 1V, unless otherwise noted. POWER TURN-ON RESPONSE POWER TURN-ON RESPONSE with 1µF Cn FPO FPO FPO V IN V IN Time (µs/div) Power Turn-On Time (10ms/div) Power Turn-On 10 POWER SUPPLY REJECTION vs FREQUEY 1. LOAD REGULATION Power Supply Rejection (db) Output Voltage Change (mv) k 10k Frequency (Hz) Output Current (ma) 00 RESPONSE TO THERMAL SHOCK 1. QUIESCENT CURRENT vs TEMPERATURE Output Voltage Change (µv) T A = C 00 0 CM Immersed in 8 C Fluorinert Bath T A = 8 C Time (s) Quiescent Current (ma) Temperature ( C)

5 TYPICAL PERFORMAE CURVES (CONT) At T A = C, V S = 1V, unless otherwise noted. TYPICAL REFEREE NOISE Noise Voltage (µv) 0 F P O 0Ω 100µF DUT 1.8kΩ Noise Test Circuit. kω OPA7 8KΩ µf Gain = 100V/V f db = 0.1Hz and 10Hz Oscilloscope Low Frequency Noise (1s /div) (See Noise Test Circuit)

6 THEORY OF OPERATION Refer to the diagram on the first page of this data sheet. The 10V output is derived from a compensated buried zener diode DZ 1, op amp A 1, and resistor network R 1 R. Approximately 8.V is applied to the non-inverting input of A 1 by DZ 1. R 1, R, and R are laser-trimmed to produce an exact 10V output. The zener bias current is established from the regulated output voltage through R. R allows usertrimming of the output voltage by providing for small external adjustment of the amplifier gain. Because the TCR of R closely matches the TCR of R 1, R and R, the voltage trim has minimal effect on the reference drift. The output voltage noise of the is dominated by the noise of the zener diode. A capacitor can be connected between the Noise Reduction pin and ground to form a low-pass filter with R and roll off the high-frequency noise of the zener. DISCUSSION OF PERFORMAE The is designed for applications requiring a precision voltage reference where both the initial value at room temperature and the drift over temperature are of importance to the user. Two basic methods of specifying voltage reference drift versus temperature are in common usage in the industry the butterfly method and the box method. The is specified with the more commonly used box method. The box is formed by the high and low specification temperatures and a diagonal, the slope of which is equal to the maximum specified drift. Since the shape of the actual drift curve is not known, the vertical position of the box is not exactly known either. It is, however, bounded by V UPPER BOUND and V LOWER BOUND (see Figure 1). Figure 1 uses the CM as an example. It has a drift specification of.ppm/ C maximum and a specification temperature range of C to 8 C. The box height, V 1 to V, is.7mv. Output Voltage (V) V 1 V NOMINAL V BM V UPPER BOUND BM V LOWER BOUND Temperature ( C) FIGURE 1. CM Output Voltage Drift..7mV Worst-case for CM INSTALLATION AND OPERATING INSTRUCTIONS BASIC CIRCUIT CONNECTION Figure shows the proper connection of the. To achieve the specified performance, pay careful attention to layout. A low resistance star configuration will reduce voltage errors, noise pickup, and noise coupled from the power supply. Commons should be connected as indicated being sure to minimize interconnection resistances. 1µF Tantalum NOTES: (1) Lead resistances here of up to a few ohms have negligible effect on performance. () A resistance of 0.1Ω in series with these leads will cause a 1mV error when the load current is at its maximum of 10mA. This results in a 0.01% error of 10V. FIGURE. Installation. OPTIONAL OUTPUT VOLTAGE ADJUSTMENT Optional output voltage adjustment circuits are shown in Figures and. Trimming the output voltage will change the voltage drift by approximately 0.008ppm/ C per mv of trimmed voltage. In the circuit in Figure, any mismatch in TCR between the two sections of the potentiometer will also affect drift, but the effect of the TCR is reduced by a factor of five by the internal resistor divider. A high quality potentiometer, with good mechanical stability, such as a cermet, should be used. The circuit in Figure has a minimum trim range of ±00mV. The circuit in Figure has less range but provides higher resolution. The mismatch in TCR between R S and the internal resistors can introduce some slight drift. This effect is minimized if R S is kept significantly larger than the 0kΩ internal resistor. A TCR of 100ppm/ C is normally sufficient. (1) V TRIM (1) () R L 1 R L R L Minimum range (±00mV) and minimal degradation of drift. 1µF Tantalum 0kΩ Output Voltage Adjust () 10V FIGURE. Optional Output Voltage Adjust.

APPLICATIONS INFORMATION 1µF Tantalum High accuracy, extremely low drift, outstanding stability, and low cost make the an ideal choice for all instrumentation and system reference applications.

7 APPLICATIONS INFORMATION 1µF Tantalum High accuracy, extremely low drift, outstanding stability, and low cost make the an ideal choice for all instrumentation and system reference applications. Figures through 1 show a variety of useful application circuits. V TRIM R S 1M Ω 0kΩ Output Voltage Adjust 10V (1.V to V) Higher resolution, reduced range (typically ±mv). FIGURE. Optional Output Voltage Fine Adjust. OPTIONAL NOISE REDUCTION The high-frequency noise of the is dominated by the zener diode noise. This noise can be greatly reduced by connecting a capacitor between the Noise Reduction pin and ground. The capacitor forms a low pass filter with R (refer to the figure on the first page of the data sheet) and attenuates the high-frequency noise generated by the zener. Figure shows the effect of a 1µF noise reduction capacitor on the high frequency noise of the. R is typically 7kΩ so the filter has a db frequency of about Hz. The result is a reduction in noise from about 800µVp-p to under 00µ Vp-p. If further noise reduction is required, use the circuit in Figure 1. 1V R S a) Resister Biased 10V Reference b) Precision 10V Reference. R 1 kω C pF OPA7 1.mA < (V I L ) <.ma R S 10V I L (1.V to V) 10V Out 10V Out See AB-00 for more detail FIGURE. 10V Reference Using a) Resistor or b) OPA7. NO C N C N = 1µF FIGURE. Effect of 1µF Noise Reduction Capacitor on Broadband Noise (f db = 1MHz). 7

8 OPA7 I L 10V 0Ω N90 R 1 = V CC 10V I L 10V I L I L (TYP) 10V a) 0mA < I L < 0mA (OPA7 also improves transient immunity) b) ma < I L < 100mA c) I L (MAX) = I L (TYP) 10mA I L (MIN) = I L (TYP) ma FIGURE 7. 10V Reference With Output Current Boosted to: a) ±0mA, b) 100mA, and c) I L (TYP) 10mA, A. 1V 7Ω 1/W 8mA 8.mA V 0 Ω Strain Gauge Bridge OPA7 R G 10 INA101 8 VOUT x100 1V V 7Ω 1/W FIGURE 8. Strain Gauge Conditioner for 0Ω Bridge. kω kω kω 10V Out 10V Out OPA111 R I OUT LOAD kω 1 See AB-00 for more details. INA10 I OUT = 10V, R 1kΩ R See AB-00 for more details and I Sink Circuit. Can be connected to ground or V. S FIGURE 9. ±10V Reference. FIGURE 10. Positive Precision Current Source. 8

9 1.V to V 10V 0V INA10 0V V 1 10V FIGURE 1. V and 10V Reference. NOTES: (1) s can be stacked to obtain voltages in multiples of 10V. () The supply voltage should be between 10n 1. and 10n where n is the number of s. () Output current of each must not exceed its rated output current of 10, ma. This includes the current delivered to the lower. (1) kω 1 R kω FIGURE 11. Stacked References. C V Out () kω 1µF OPA7 R1 1k Ω C 1 1µF 10V V REF INA10 V Out (N) kω N V REF = (V O1 V O... N ) N e N = µvp-p (f = 0.1Hz to 1Mhz) 1 N See AB-00 for more details. FIGURE 1. ±V Reference. FIGURE 1. Precision Voltage Reference with Extremely Low Noise. 9

Precision VOLTAGE REFERENCE

Precision VOLTAGE REFERENCE FEATURES +.PUT HIGH ACCURACY: ±.V VERY LOW DRIFT: ppm/ C max EXCELLENT STABILITY: ppm/hrs LOW NOISE: µvp-p typ,.hz to Hz WIDE SUPPLY RANGE: Up to V LOW QUIESCENT CURRENT: ma