N.C. OUT. Maxim Integrated Products 1

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1 ; Rev 2; 11/6 Ultra-Low-Power Precision Series General Description The MAX629 micropower, low-dropout bandgap voltage reference combines ultra-low supply current and low drift in a miniature 5-pin SOT23 surface-mount package that uses 7% less board space than comparable devices in an SO package. An initial accuracy of.15% and a 3ppm/ C (max) temperature coefficient make the MAX629 suitable for precision applications. This series-mode voltage reference sources up to 4mA and sinks up to 1mA of load current. A wide 2.5V to 12.6V supply range, ultra-low 5.25µA (max) supply current, and a low 2mV dropout voltage make these devices ideal for battery-operated systems. Additionally, an internal compensation capacitor eliminates the need for an external compensation capacitor and ensures stability with load capacitances up to 1µF. The MAX629 provides six output voltages of 2.48V, 2.5V, 3V, 3.3V, 4.96V, and 5V. The MAX629 is available in a 5-pin SOT23 or an 8-pin SO package and is specified over the extended temperature range (-4 C to +85 C). Battery-Powered Systems Hand-Held Instruments Precision Power Supplies A/D and D/A Converters Applications Features Ultra-Low 5.25µA (max) Supply Current ±.15% (max) Initial Accuracy 3ppm/ C (max) Temperature Coefficient 4mA Output Source Current 1mA Output Sink Current 2.5V to 12.6V Supply Range Low 2mV Dropout Stable with Capacitive Loads Up to 1µF No External Capacitors Required Miniature 5-Pin SOT23 Package, 8-Pin SO Package PART Ordering Information PIN-PACKAGE TOP MARK PKG CODE MAX629EUK21-T 5 SOT23-5 AEHD U5-1 MAX629EUK25-T 5 SOT23-5 AEHF U5-1 MAX629ESA25 8 SO S8-2 MAX629EUK3-T 5 SOT23-5 AEHH U5-1 MAX629EUK33-T 5 SOT23-5 AEHN U5-1 MAX629EUK41-T 5 SOT23-5 AEHJ U5-1 MAX629ESA41 8 SO S8-2 MAX629EUK5-T 5 SOT23-5 AEHL U5-1 Note: All devices are specified over the -4 C to +85 C operating temperature range. MAX629 Pin Configurations Selector Guide TOP VIEW PART PIN-PACKAGE OUTPUT VOLTAGE (V) MAX629EUK21-T 5 SOT IN GND N.C. 1 5 OUT MAX N.C. N.C. IN N.C. GND MAX N.C. N.C. OUT N.C. MAX629EUK25-T 5 SOT MAX629ESA25 8 SO 2.5 MAX629EUK3-T 5 SOT MAX629EUK33-T 5 SOT MAX629EUK41-T 5 SOT MAX629ESA41 8 SO 4.96 SOT23 SO MAX629EUK5-T 5 SOT Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 MAX629 ABSOLUTE MAXIMUM RATINGS IN to GND...-.3V to +13V OUT to GND...-.3V to the lower of +6V and (V IN +.3V) Output to GND Short-Circuit Duration...Continuous Continuous Power Dissipation (T A = +7 C) 5-Pin SOT23 (derate 7.1mW/ C above +7 C)...571mW 8-Pin SO (derate 5.9mW/ C above +7 C) mW Operating Temperature Range...-4 C to +85 C Storage Temperature Range C to +15 C Lead Temperature (soldering, 1s)...+3 C Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS MAX629_21 (VOUT = 2.48V) (V IN = 2.5V, I OUT =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUTPUT Output Voltage T A = +25 C V Output Voltage Temperature Coefficient TC (Notes 2, 3) 3 ppm/ C Line Regulation / V IN V IN = 2.5V to 12.6V 27 2 µv/v Load Regulation / I OUT = to 4mA.22.7 I OUT IOUT = to -1mA Output Short-Circuit Current I SC 6 ma Long-Term Stability /time 1 hours at +25 C 15 ppm Thermal Hysteresis (Note 4) 14 ppm DYNAMIC CHARACTERISTICS f =.1Hz to 1Hz 3 µv P-P Noise Voltage e OUT f = 1Hz to 1kHz 115 µv RMS Ripple Rejection / V IN V IN = 2.5V ±2mV, f = 12Hz 43 db Turn-On Settling Time t R To =.1% of final value 45 µs INPUT Supply Voltage Range V IN V Supply Current I IN 5.25 µa Change in Supply Current I IN /V IN V IN = 2.5V to 12.6V 1.5 µa/v µv/µa 2

3 ELECTRICAL CHARACTERISTICS MAX629_25 (VOUT = 2.5V) (V IN = 2.7V, I OUT =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage T A = +25 C Output Voltage Temperature Coefficient MAX629EUK MAX629ESA TC (Notes 2, 3) 3 ppm/ C V MAX629 Line Regulation / V IN V IN = 2.7V to 12.6V 3 23 µv/v I OUT = to 4mA.1.6 Load Regulation / I OUT IOUT = to -1mA µv/µa I OUT = 1 Dropout Voltage (Note 5) V IN - I OUT = 4mA 2 mv Output Short-Circuit Current I SC 6 ma Long-Term Stability /time 1 hours at +25 C 15 ppm Thermal Hysteresis (Note 4) 14 ppm DYNAMIC CHARACTERISTICS f =.1Hz to 1Hz 39 µv P-P Noise Voltage e OUT f = 1Hz to 1kHz 137 µv RMS Ripple Rejection / V IN V IN = 2.7V ±2mV, f = 12Hz 34 db Turn-On Settling Time t R To =.1% of final value 7 ms INPUT Supply Voltage Range V IN V Supply Current I IN 5.75 µa Change in Supply Current I IN /V IN V IN = 2.7V to 12.6V 1.5 µa/v 3

4 MAX629 ELECTRICAL CHARACTERISTICS MAX629_3 (VOUT = 3.V) (V IN = 3.2V, I OUT =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage T A = +25 C V Output Voltage Temperature Coefficient TC (Notes 2, 3) 3 ppm/ C Line Regulation / V IN V IN = 3.2V to 12.6V µv/v Load Regulation / I OUT = to 4mA.1.6 I OUT IOUT = to -1mA I OUT = 1 Dropout Voltage (Note 5) V IN - I OUT = 4mA 2 µv/µa mv Output Short-Circuit Current I SC 6 ma Long-Term Stability /time 1 hours at +25 C 15 ppm Thermal Hysteresis (Note 4) 14 ppm DYNAMIC CHARACTERISTICS f =.1Hz to 1Hz 39 µv P-P Noise Voltage e OUT f = 1Hz to 1kHz 161 µv RMS Ripple Rejection / V IN V IN = 3.2V ±2mV, f = 12Hz 37 db Turn-On Settling Time t R To =.1% of final value 775 µs INPUT Supply Voltage Range V IN V Supply Current I IN 6.75 µa Change in Supply Current I IN /V IN V IN = 3.2V to 12.6V 1.5 µa/v 4

5 ELECTRICAL CHARACTERISTICS MAX629_33 (VOUT = 3.3V) (V IN = 3.5V, I OUT =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage T A = +25 C V Output Voltage Temperature Coefficient TC (Notes 2, 3) 3 ppm/ C Line Regulation / V IN V IN = 3.5V to 12.6V 3 27 µv/v I OUT = to 4mA.1.6 Load Regulation / I OUT IOUT = to -1mA µv/µa MAX629 I OUT = 1 Dropout Voltage (Note 5) V IN - I OUT = 4mA 2 mv Output Short-Circuit Current I SC 6 ma Long-Term Stability /time 1 hours at +25 C 15 ppm Thermal Hysteresis (Note 4) 14 ppm DYNAMIC CHARACTERISTICS f =.1Hz to 1Hz 56 µv P-P Noise Voltage e OUT f = 1Hz to 1kHz 174 µv RMS Ripple Rejection / V IN V IN = 3.5V ±2mV, f = 12Hz 38 db Turn-On Settling Time t R To =.1% of final value 1 ms INPUT Supply Voltage Range V IN V Supply Current I IN 7.25 µa Change in Supply Current I IN /V IN V IN = 3.5V to 12.6V 1.5 µa/v 5

6 MAX629 ELECTRICAL CHARACTERISTICS MAX629_41 (VOUT = 4.96V) (V IN = 4.3V, I OUT =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage T A = +25 C Output Voltage Temperature Coefficient MAX629EUK MAX629ESA TC (Notes 2, 3) 3 ppm/ C V Line Regulation / V IN V IN = 4.3V to 12.6V 3 31 µv/v I OUT = to 4mA.1.6 Load Regulation / I OUT IOUT = to -1mA µv/µa I OUT = 1 Dropout Voltage (Note 5) V IN - I OUT = 4mA 2 mv Output Short-Circuit Current I SC 6 ma Long-Term Stability /time 1 hours at +25 C 15 ppm Thermal Hysteresis (Note 4) 14 ppm DYNAMIC CHARACTERISTICS f =.1Hz to 1Hz 72 µv P-P Noise Voltage e OUT f = 1Hz to 1kHz 21 µv RMS Ripple Rejection / V IN V IN = 4.3V ±2mV, f = 12Hz 36 db Turn-On Settling Time t R To =.1% of final value 1.2 ms INPUT Supply Voltage Range V IN V Supply Current I IN 8.75 µa Change in Supply Current I IN /V IN V IN = 4.3V to 12.6V 1.5 µa/v 6

7 ELECTRICAL CHARACTERISTICS MAX629_5 (VOUT = 5.V) (V IN = 5.2V, I OUT =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at T A = +25 C.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage T A = +25 C V Output Voltage Temperature Coefficient TC (Notes 2, 3) 3 ppm/ C Line Regulation / V IN V IN = 5.2V to 12.6V µv/v Load Regulation / I OUT = to 4mA.3.8 I OUT IOUT = to -1mA I OUT = 1 Dropout Voltage (Note 5) V IN - I OUT = 4mA 2 µv/µa mv MAX629 Output Short-Circuit Current I SC 6 ma Long-Term Stability /time 1 hours at +25 C 15 ppm Thermal Hysteresis (Note 4) 14 ppm DYNAMIC CHARACTERISTICS f =.1Hz to 1Hz 9 µv P-P Noise Voltage e OUT f = 1Hz to 1kHz 245 µv RMS Ripple Rejection / V IN V IN = 5.2V ±2mV, f = 12Hz 38 db Turn-On Settling Time t R To =.1% of final value 1.4 ms INPUT Supply Voltage Range V IN V Supply Current I IN 1.5 µa Change in Supply Current I IN /V IN V IN = 5.2V to 12.6V 1.5 µa/v Note 1: MAX629 is 1% production tested at T A = +25 C and is guaranteed by design for T A = T MIN to T MAX as specified. Note 2: Temperature coefficient is defined by box method: (V MAX - V MIN )/( T V +25 C ). Note 3: Not production tested. Guaranteed by design. Note 4: Thermal hysteresis is defined as the change in T A = +25 C output voltage before and after temperature cycling of the device (from T A = T MIN to T MAX ). Initial measurement at T A = +25 C is followed by temperature cycling the device to T A = +85 C then to T A = -4 C and another measurement at T A = +25 C is compared to the original measurement at T A = +25 C. Note 5: Dropout voltage is the minimum input voltage at which changes by.1% from at rated V IN and is guaranteed by Load Regulation Test. 7

8 MAX629 Typical Operating Characteristics (V IN = 2.5V for MAX629EUK21, V IN = 3.2V for MAX629EUK3, and V IN = 5.2V for MAX629EUK5, I OUT =, T A = +25 C, unless otherwise noted.) OUTPUT VOLTAGE vs. TEMPERATURE ( = 2.48V) 3 TYPICAL UNITS MAX629 toc OUTPUT VOLTAGE vs. TEMPERATURE ( = 3V) 3 TYPICAL UNITS MAX629 toc OUTPUT VOLTAGE vs. TEMPERATURE ( = 5V) 3 TYPICAL UNITS MAX629 toc TEMPERATURE ( C) TEMPERATURE ( C) TEMPERATURE ( C) SUPPLY CURRENT (µa) SUPPLY CURRENT vs. INPUT VOLTAGE = 3V = 2.48V = 5V MAX629 toc4 SUPPLY CURRENT (µa) SUPPLY CURRENT vs. TEMPERATURE = 5V = 3V = 2.48V MAX629 toc5 DROPOUT VOLTAGE (V) DROPOUT VOLTAGE vs. SOURCE CURRENT ( = 2.48V) MAX629 toc INPUT VOLTAGE (V) TEMPERATURE ( C) SOURCE CURRENT (ma) DROPOUT VOLTAGE (V) DROPOUT VOLTAGE vs. SOURCE CURRENT ( = 3V) SOURCE CURRENT (ma) MAX629 toc7 DROPOUT VOLTAGE (V) DROPOUT VOLTAGE vs. SOURCE CURRENT ( = 5V) SOURCE CURRENT (ma) MAX629 toc8 LOAD REGULATION ( = 2.48V) OUTPUT CURRENT (ma) MAX629 toc9 8

9 Typical Operating Characteristics (continued) (V IN = 2.5V for MAX629EUK21, V IN = 3.2V for MAX629EUK3, and V IN = 5.2V for MAX629EUK5, I OUT =, T A = +25 C, unless otherwise noted.) LINE REGULATION ( = 2.48V) INPUT VOLTAGE (V) MAX629 toc LOAD REGULATION ( = 3V) OUTPUT CURRENT (ma) MAX629 toc LINE REGULATION ( = 3V) INPUT VOLTAGE (V) MAX629 toc12 MAX LOAD REGULATION ( = 5V) MAX629 toc LINE REGULATION ( = 5V) MAX629 toc14 PSRR (db) POWER-SUPPLY REJECTION RATIO vs. FREQUENCY ( = 2.48V) MAX629 toc OUTPUT CURRENT (ma) INPUT VOLTAGE (V) FREQUENCY (khz) PSRR (db) POWER-SUPPLY REJECTION RATIO vs. FREQUENCY ( = 3V) MAX629 toc16 PSRR (db) POWER-SUPPLY REJECTION RATIO vs. FREQUENCY ( = 5V) MAX629 toc17 3V 2.5V 2.48V LINE-TRANSIENT RESPONSE ( = 2.48V) MAX629 toc18 V IN 2mV/div 2mV/div FREQUENCY (khz) FREQUENCY (khz) 2µs/div 9

10 MAX629 Typical Operating Characteristics (continued) (V IN = 2.5V for MAX629EUK21, V IN = 3.2V for MAX629EUK3, and V IN = 5.2V for MAX629EUK5, I OUT =, T A = +25 C, unless otherwise noted.) 3.7V LINE-TRANSIENT RESPONSE ( = 3V) MAX629 toc19 V IN 2mV/div 5.7V LINE-TRANSIENT RESPONSE ( = 5V) MAX6129 toc2 V IN 2mV/div 3.2V 5.2V 3V 2mV/div 5V 1mV/div 2µs/div 2µs/div C OUT = LOAD-TRANSIENT RESPONSE (SOURCING, = 2.48V) MAX629 toc21 C OUT = LOAD-TRANSIENT RESPONSE (SINKING, = 2.48V) MAX629 toc22 4mA I OUT 1mA/div -1mA I OUT 2mA/div 2.48V 5mV/div 2.48V 5mV/div 1µs/div 1ms/div LOAD-TRANSIENT RESPONSE (SOURCING, = 2.48V) C OUT = 1µF MAX629 toc23 LOAD-TRANSIENT RESPONSE (SINKING, = 2.48V) C OUT = 1µF MAX629 toc24 4mA I OUT 1mA/div -1mA I OUT 2mA/div 2.48V 5mV/div 2.48V 5mV/div 4µs/div 1ms/div 1

11 Typical Operating Characteristics (continued) (V IN = 2.5V for MAX629EUK21, V IN = 3.2V for MAX629EUK3, and V IN = 5.2V for MAX629EUK5, I OUT =, T A = +25 C, unless otherwise noted.) 4mA C OUT = LOAD-TRANSIENT RESPONSE (SOURCING, = 5V) MAX629 toc25 I OUT 1mA/div -1mA C OUT = LOAD-TRANSIENT RESPONSE (SINKING, = 5V) MAX629 toc26 I OUT 1mA/div MAX629 5V 5mV/div 5V 1V/div 4µs/div 2ms/div LOAD-TRANSIENT RESPONSE (SOURCING, = 5V) C OUT = 1µF 629 toc27 LOAD-TRANSIENT RESPONSE (SINKING, = 5V) C OUT = 1µF MAX629 toc28 4mA I OUT 1mA/div -1mA I OUT 1mA/div 6V 2mV/div 5V 1V/div 4µs/div 2ms/div TURN-ON TRANSIENT ( = 2.48V) MAX629 toc29 TURN-ON TRANSIENT ( = 3V) MAX629 toc3 2.5V V IN 1V/div 3.2V V IN 2V/div 2.48V 1V/div 3V 1V/div 2µs/div 2µs/div 11

MAX629 Typical Operating Characteristics (continued) (V IN = 2.5V for MAX629EUK21, V IN = 3.2V for MAX629EUK3, and V IN = 5.2V for MAX629EUK5, I OUT =, T A = +25 C, unless otherwise noted.) 5.

1Hz TO 1Hz OUTPUT NOISE ( = 5V) MAX629 toc34 2µV/div NOISE (µvrms/ Hz) 4. 3.5 3. 2.5 2. 1.5 NOISE vs. FREQUENCY ( = 2.48V) MAX629 toc35 1..5 1s/div 1 2 3 4 5 FREQUENCY (khz) NOISE (µvrms/ Hz) 6.5 6.

12 MAX629 Typical Operating Characteristics (continued) (V IN = 2.5V for MAX629EUK21, V IN = 3.2V for MAX629EUK3, and V IN = 5.2V for MAX629EUK5, I OUT =, T A = +25 C, unless otherwise noted.) 5.2V TURN-ON TRANSIENT ( = 5V) MAX629 toc31 V IN 2V/div.1Hz TO 1Hz OUTPUT NOISE ( = 2.48V) MAX629 toc32.1hz TO 1Hz OUTPUT NOISE ( = 3V) MAX629 toc33 5V 1µV/div 1µV/div 2V/div 4µs/div 1s/div 1s/div.1Hz TO 1Hz OUTPUT NOISE ( = 5V) MAX629 toc34 2µV/div NOISE (µvrms/ Hz) NOISE vs. FREQUENCY ( = 2.48V) MAX629 toc s/div FREQUENCY (khz) NOISE (µvrms/ Hz) NOISE vs. FREQUENCY ( = 3V) FREQUENCY (khz) MAX629 toc36 NOISE (µvrms/ Hz) NOISE vs. FREQUENCY ( = 5V) FREQUENCY (khz) MAX629 toc37 12

13 SOT23 PIN SO NAME Pin Description FUNCTION 1 2 IN Positive Voltage Supply 2 4 GND Ground 3, 4 1, 3, 5, 7, 8 N.C. No Connection. Leave unconnected or connect to ground. 5 6 OUT Reference Output Applications Information Input Bypassing The MAX629 does not require an input bypass capacitor. For improved transient performance, bypass the input to ground with a.1µf ceramic capacitor. Place the capacitor as close to IN as possible. Load Capacitance The MAX629 does not require an output capacitor for stability. The MAX629 is stable driving capacitive loads from to 1pF and.1µf to 1µF when sourcing current and from to.4µf when sinking current. In applications where the load or the supply can experience step changes, an output capacitor reduces the amount of overshoot (undershoot) and improves the circuit s transient response. Many applications do not require an external capacitor, and the MAX629 offers a significant advantage in applications where board space is critical. Supply Current The quiescent supply current of the series-mode MAX629 is very small, 5.25µA (max), and is very stable against changes in the supply voltage with only 1.5µA/V (max) variation with supply voltage. The MAX629 family draws load current from the input voltage source only when required, so supply current is not wasted and efficiency is maximized at all input voltages. This improved efficiency reduces power dissipation and extends battery life. Output Thermal Hysteresis Output thermal hysteresis is the change of the output voltage at T A = +25 C before and after the device is cycled over its entire operating temperature range. Hysteresis is caused by differential package stress appearing across the device. Temperature Coefficient vs. Operating Temperature Range for a 1LSB Maximum Error In a data converter application, the reference voltage of the converter must stay within a certain limit to keep the error in the data converter smaller than the resolution limit through the operating temperature range. Figure 1 shows the maximum allowable reference voltage temperature coefficient to keep the conversion error to less than 1 LSB, as a function of the operating temperature range (T MAX - T MIN ) with the converter resolution as a parameter. The graph assumes the reference-voltage temperature coefficient as the only parameter affecting accuracy. In reality, the absolute static accuracy of a data converter is dependent on the combination of many parameters such as integral nonlinearity, differential nonlinearity, offset error, gain error, as well as voltage reference changes. Turn-On Time These devices turn on and settle to within.1% of their final value in less than 1ms. The turn-on time increases when heavily loaded and operating close to dropout. MAX629 1, 1 TEMPERATURE COEFFICIENT (ppm/ C) 1 8-BIT 1 1-BIT 12-BIT 1 14-BIT.1 16-BIT 18-BIT.1 2-BIT OPERATING TEMPERATURE RANGE (T MAX - T MIN ) ( C) Figure 1. Temperature Coefficient vs. Operating Temperature Range for a 1 LSB Maximum Error 13

14 MAX629 Typical Operating Circuit V IN = 2.5V TO 12.6V * IN TRANSISTOR COUNT: 3 PROCESS: BiCMOS Chip Information MAX629 OUT GND *CAPACITOR IS OPTIONAL. 14

15 Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to SOT-23 5L.EPS MAX629 15

16 MAX629 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to N E H INCHES MILLIMETERS DIM MIN MAX MIN MAX A A B C e.5 BSC 1.27 BSC E H L SOICN.EPS 1 TOP VIEW VARIATIONS: DIM D D D INCHES MILLIMETERS MIN MAX MIN MAX N MS AA AB AC D A C e B A1 FRONT VIEW L SIDE VIEW -8 PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE,.15" SOIC APPROVAL DOCUMENT CONTROL NO. REV B 1 1 Pages changed at Rev 1: 1, 2, 13, 15, 16 Pages changed at Rev 2: 1, 3, 6, 16 Revision History Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 16 Maxim Integrated Products, 12 San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.

Ultra-Low-Power Precision Series Voltage Reference MAX6029. Features. General Description. Ordering Information. Applications.

Ultra-Low-Power Precision Series Voltage Reference MAX6029. Features. General Description. Ordering Information. Applications. MAX629 General Description The MAX629 micropower, low-dropout bandgap voltage reference combines ultra-low supply current and low drift in a miniature 5-pin SOT23 surface-mount package that uses 7% less