Precision, Micropower, Low-Dropout, SC70 Series Voltage Reference

Transcription

1 ; Rev ; 4/2 Precision, Micropower, Low-Dropout, SC7 General Description The family of precision, low-dropout, micropower voltage references are available in the miniature 3-pin SC7 surface-mount package. They feature a proprietary temperature coefficient curvature-correction circuit and laser-trimmed, thin-film resistors that result in a low temperature coefficient of 3ppm/ C (max) and initial accuracy of ±.2% (max). These devices are available over the extended temperature range of -4 C to +85 C. The family of series-mode voltage references typically draw only 9µA of supply current and can source 1mA and sink 2µA of load current. Unlike conventional shunt-mode (two terminal) references that waste supply current and require an external resistor, devices in the family offer supply current that is virtually independent of supply voltage (16µA/V, max variation) and do not require an external resistor. These internally compensated devices do not require an external compensation capacitor, but are stable with up to 1µF of load capacitance. Eliminating the external compensation capacitor saves valuable board space in space-critical applications. The low dropout voltage and supply-independent, ultra-low supply current make the ideal for battery-powered applications. Applications Hand-Held Equipment Data-Acquisition Systems Industrial and Process Control Systems Battery-Operated Equipment Hard-Disk Drives Typical Operating Circuit +SUPPLY INPUT (SEE SELECTOR GUIDE) Features Ultra-Small, 3-Pin SC7 Package ±.2% (max) Initial Accuracy 3ppm/ C (max) Temperature Coefficient 9µA Supply Current 2mV (max) Dropout Voltage at 1mA Load Current Stable with C LOAD = to 1µF No Output Capacitor Needed PART Ordering Information TEMP RANGE PI N - PA C K A G E TOP MARK AEXR21-T -4 C to +85 C 3 SC7-3 AJH BEXR21-T -4 C to +85 C 3 SC7-3 AJM AEXR25-T -4 C to +85 C 3 SC7-3 AJI BEXR25-T -4 C to +85 C 3 SC7-3 AJN AEXR3-T -4 C to +85 C 3 SC7-3 AJJ BEXR3-T -4 C to +85 C 3 SC7-3 AJO AEXR33-T -4 C to +85 C 3 SC7-3 AJK BEXR33-T -4 C to +85 C 3 SC7-3 AJP AEXR41-T -4 C to +85 C 3 SC7-3 AJL BEXR41-T -4 C to +85 C 3 SC7-3 AJQ Selector Guide PART INPUT VOLTAGE (V) _EXR21-T to 5.5 _EXR25-T 2.5 ( + 2mV) to 5.5 _EXR3-T 3. ( + 2mV) to 5.5 _EXR33-T 3.3 ( + 2mV) to 5.5 _EXR41-T 4.96 ( + 2mV) to 5.5 IN Pin Configuration * OUT REFERENCE OUT TOP VIEW IN 1 GND 3 GND OUT 2 *CAPACITOR IS OPTIONAL. SC7 Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 Precision, Micropower, Low-Dropout, SC7 ABSOLUTE MAXIMUM RATINGS (Voltages Referenced to GND) IN...-.3V to +6.V OUT...-.3V to (V IN +.3V) Output Short Circuit to GND or IN...Continuous Continuous Power Dissipation (T A = +7 C) 3-Pin SC7 (derate 2.9mW/ C above +7 C)...235mW Operating Temperature Range...-4 C to +85 C Junction Temperature 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 _21 (VOUT = 2.48V) (V IN = 2.7V, =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage Output Voltage Temperature Coefficient (Note 2) Line Regulation Load Regulation A_21 (±.2%) B_21 (±.4%) A_ TC B_ V ppm/ C 2.5V V IN 5.5V µv/v Sourcing: 1mA Sinking: IOUT 2µA Short to GND 12 OUT Short-Circuit Current I SC Short to IN 4 Temperature Hysteresis Long-Term Stability cycle time mv/ma (Note 3) 1 ppm 1hr at 9 ma ppm/ 1hr DYNAMIC Noise Voltage e OUT f =.1Hz to 1Hz 45 µv P-P f = 1Hz to 1kHz 46 µv RMS Ripple Rejection V IN = 2.7V ±1mV, f = 12Hz 8 db Turn-On Settling Time t R To =.1% of final value, C OUT = 5pF 85 µs Capacitive-Load Stability Range C OUT (Note 4) 1 µf INPUT Supply Voltage Range V IN Guaranteed by line-regulation test V Quiescent Supply Current I IN µa Change in Supply Current Per Change in Input Voltage I IN / 2.5V V IN 5.5V µa/v 2

3 Precision, Micropower, Low-Dropout, SC7 ELECTRICAL CHARACTERISTICS _25 (VOUT = 2.5V) (V IN = 2.7V, =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage Output Voltage Temperature Coefficient (Note 2) Line Regulation Load Regulation A_25 (±.2%) B_25 (±.4%) A_ TC B_ V ppm/ C ( + 2mV) V IN 5.5V 4 25 µv/v Sourcing: 1mA Sinking: IOUT 2µA Short to GND 12 OUT Short-Circuit Current I SC Short to IN 4 mv/ma ma Dropout Voltage Temperature Hysteresis Long-Term Stability V IN - = 1mA (Note 5) 7 2 mv cycle time (Note 3) 1 ppm 1hr at 9 ppm/ 1hr DYNAMIC Noise Voltage e OUT f =.1Hz to 1Hz 55 µv P-P f = 1Hz to 1kHz 64 µv RMS Ripple Rejection V IN = 2.7V ±1mV, f = 12Hz 8 db Turn-On Settling Time t R To =.1% of final value, C OUT = 5pF 14 µs Capacitive-Load Stability Range C OUT (Note 4) 1 µf INPUT Supply Voltage Range V IN Guaranteed by line-regulation test VOUT V Quiescent Supply Current I IN µa Change in Supply Current Per Change in Input Voltage I IN / ( + 2mV) V IN 5.5V µa/v 3

4 Precision, Micropower, Low-Dropout, SC7 ELECTRICAL CHARACTERISTICS _3 (VOUT = 3.V) (V IN = 5V, =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS A_3 (±.2%) Output Voltage B_3 (±.4%) Output Voltage Temperature A_3 7 3 TC Coefficient (Note 2) B_ Line Regulation Load Regulation V ppm/ C ( + 2mV) V IN 5.5V µv/v Sourcing: 1mA Sinking: 2µA Short to GND 13 OUT Short-Circuit Current I SC Short to IN 4 mv/ma ma Dropout Voltage V IN - V OU T = 1mA (Note 5) 7 2 mv Temperature Hysteresis Long-Term Stability cycle time (Note 3) 1 ppm 1hr at 9 ppm/ 1hr DYNAMIC Noise Voltage e OUT f =.1Hz to 1Hz 66 µv P-P f = 1Hz to 1kHz 8 µv RMS Ripple Rejection V IN = 5V ±1mV, f = 12Hz 76 db Turn-On Settling Time t R To =.1% of final value, C OUT = 5pF 165 µs Capacitive-Load Stability Range C OUT (Note 4) 1 µf INPUT Supply Voltage Range V IN Guaranteed by line-regulation test V Quiescent Supply Current I IN µa Change in Supply Current Per Change in Input Voltage I IN / ( + 2mV) V IN 5.5V µa/v 4

5 Precision, Micropower, Low-Dropout, SC7 ELECTRICAL CHARACTERISTICS _33 (VOUT = 3.3V) (V IN = 5V, =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Output Voltage Output Voltage Temperature Coefficient (Note 2) Line Regulation Load Regulation A_33 (±.2%) B_33 (±.4%) A_ TC B_ V ppm/ C ( + 2mV) V IN 5.5V 45 3 µv/v Sourcing: 1mA Sinking: IOUT 2µA Short to GND 13 OUT Short-Circuit Current I SC Short to IN 4 mv/ma ma Dropout Voltage V IN - V OU T = 1mA (Note 5) 7 2 mv Temperature Hysteresis Long-Term Stability cycle time (Note 3) 1 ppm 1hr at 9 ppm/ 1hr DYNAMIC Noise Voltage e OUT f =.1Hz to 1Hz 73 µv P-P f = 1Hz to 1kHz 88 µv RMS Ripple Rejection V IN = 5V ±1mV, f = 12Hz 76 db Turn-On Settling Time t R To =.1% of final value, C OUT = 5pF 2 µs Capacitive-Load Stability Range C OUT (Note 4) 1 µf INPUT Supply Voltage Range V IN Guaranteed by line-regulation test V Quiescent Supply Current I IN µa Change in Supply Current Per Change in Input Voltage I IN / ( + 2mV) V IN 5.5V µa/v 5

6 Precision, Micropower, Low-Dropout, SC7 ELECTRICAL CHARACTERISTICS _41 (VOUT = 4.96V) (V IN = 5V, =, T A = T MIN to T MAX, unless otherwise noted. Typical values are at.) (Note 1) OUTPUT PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS A_41 (±.2%) Output Voltage B_41 (±.4%) Output Voltage Temperature A_ TC Coefficient (Note 2) B_ Line Regulation Load Regulation V ppm/ C ( + 2mV) V IN 5.5V 5 35 µv/v Sourcing: 1mA Sinking: 2µA Short to GND 13 OUT Short-Circuit Current I SC Short to IN 7 mv/ma ma Dropout Voltage V IN - V OU T = 1mA (Note 5) 7 2 mv Temperature Hysteresis Long-Term Stability cycle time (Note 3) 1 ppm 1hr at 9 ppm/ 1hr DYNAMIC Noise Voltage e OUT f =.1Hz to 1Hz 9 µv P-P f = 1Hz to 1kHz 15 µv RMS Ripple Rejection V IN = 5V ±1mV, f = 12Hz 73 db Turn-On Settling Time t R To =.1% of final value, C OUT = 5pF 26 µs Capacitive-Load Stability Range C OUT (Note 4) 1 µf INPUT Supply Voltage Range V IN Guaranteed by line-regulation test V Quiescent Supply Current I IN µa Change in Supply Current Per Change in Input Voltage I IN / ( + 2mV) V IN 5.5V µa/v Note 1: All devices are 1% production tested at and are guaranteed by design for T A = T MIN to T MAX as specified. Note 2: Temperature coefficient is measured by the box method, i.e. the maximum is divided by the maximum T. Note 3: Temperature hysteresis is defined as the change in +25 C output voltage after cycling the device from T MIN to T MAX. Note 4: Not production tested. Guaranteed by design. Note 5: Dropout voltage is defined as the minimum differential voltage (V IN - ) at which decreases by.2% from its original value at V IN = 5.V (V IN = 2.7V for _25). 6

7 Precision, Micropower, Low-Dropout, SC7 Typical Operating Characteristics (V IN = 2.7V for _21/25, V IN = 5V for _3/33/41, =,, unless otherwise noted.) (Note 6) OUTPUT VOLTAGE (V) _21 OUTPUT VOLTAGE TEMPERATURE DRIFT ( = 2.48V) THREE TYPICAL PARTS toc1 OUTPUT VOLTAGE (V) _41 OUTPUT VOLTAGE TEMPERATURE DRIFT ( = 4.96V) THREE TYPICAL PARTS toc2 OUTPUT VOLTAGE (V) _21 LONG-TERM DRIFT ( = 2.48V) toc3 OUTPUT VOLTAGE (V) TEMPERATURE ( C) _41 LONG-TERM DRIFT ( = 4.96V) toc4 SUPPLY CURRENT (µa) TEMPERATURE ( C) SUPPLY CURRENT vs. SUPPLY VOLTAGE toc5 SUPPLY CURRENT (µa) TIME (hr) SUPPLY CURRENT vs. TEMPERATURE V IN = 5.5V V IN = 2.7V toc _25 DROPOUT VOLTAGE vs. SOURCE CURRENT ( = 2.5V) TIME (hr) toc SUPPLY VOLTAGE (V).15 _25 DROPOUT VOLTAGE vs. SINK CURRENT ( = 2.5V) toc _41 DROPOUT VOLTAGE vs. SOURCE CURRENT ( = 4.96V).6.5 TEMPERATURE ( C) toc9 DROPOUT VOLTAGE (V) DROPOUT VOLTAGE (V).1.5 DROPOUT VOLTAGE (V) T A = -4 C T A = -4 C.1 T A = -4 C SOURCE CURRENT (ma) SINK CURRENT (ma) SOURCE CURRENT (ma) 7

8 Precision, Micropower, Low-Dropout, SC7 Typical Operating Characteristics (continued) (V IN = 2.7V for _21/25, V IN = 5V for _3/33/41, =,, unless otherwise noted.) (Note 6) DROPOUT VOLTAGE (V) _41 DROPOUT VOLTAGE vs. SINK CURRENT ( = 4.96V) SINK CURRENT (ma) T A = -4 C toc1 OUTPUT VOLTAGE CHANGE (mv) T A = -4 C SINK _21 LOAD REGULATION ( = 2.48V) T A = -4 C SOURCE LOAD CURRENT (ma) toc11 OUTPUT VOLTAGE CHANGE (mv) T A = -4 C SINK _41 LOAD REGULATION ( = 4.96V) SOURCE T A = -4 C LOAD CURRENT (ma) toc12 OUTPUT VOLTAGE CHANGE (µv) _25 LINE REGULATION ( = 2.5V) T A = -4 C toc13 PSRR (db) _25 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY ( = 2.5V) toc14 PSRR (db) _41 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY ( = 4.96V) toc INPUT VOLTAGE (V) FREQUENCY (khz) FREQUENCY (khz) _25 LINE TRANSIENT ( = 2.5V) toc16 _41 LINE TRANSIENT ( = 4.96V) toc V V IN 2.7V 5.5V V IN 5.V 5mV/div 1mV/div C LOAD = C LOAD = 1µs 1µs 8

9 Precision, Micropower, Low-Dropout, SC7 Typical Operating Characteristics (continued) (V IN = 2.7V for _21/25, V IN = 5V for _3/33/41, =,, unless otherwise noted.) (Note 6) _25 toc18 +1µA -1µA _25 toc19 +1µA -1µA C LOAD = I LOAD = ±1µA = 2.5V 1mV/div C LOAD = 1µF I LOAD = ±1µA = 2.5V 2mV/div _41 toc2 _41 toc21 +1µA -1µA +1µA -1µA C LOAD = I LOAD = ±1µA = 4.96V 1mV/div C LOAD = 1µF I LOAD = ±1µA = 4.96V 2mV/div _25 toc22 _25 toc23 +1mA +1mA -.2mA -.2mA C LOAD = I LOAD = +1mA/-.2mA = 2.5V 1mV/div C LOAD = 1µF I LOAD = +1mA/-.2mA = 2.5V 2mV/div 9

10 Precision, Micropower, Low-Dropout, SC7 Typical Operating Characteristics (continued) (V IN = 2.7V for _21/25, V IN = 5V for _3/33/41, =,, unless otherwise noted.) (Note 6) _41 toc24 +1mA -.2mA _41 toc25 +1mA -.2mA _25 TURN-ON TRANSIENT toc26 2.7V V IN C LOAD = I LOAD = +1mA/-.2mA = 4.96V 1mV/div C LOAD = 1µF I LOAD = +1mA/-.2mA = 4.96V 5mV/div C LOAD = 5pF = 2.5V 2.5V 4µs _41 TURN-ON TRANSIENT toc27 _25 OUTPUT NOISE (.1Hz TO 1Hz) = 2.5V toc28 _41 OUTPUT NOISE (.1Hz TO 1Hz) = 4.96V toc29 5V V IN 4.96V 5µV/div 5µV/div C LOAD = 5pF = 4.96V 4µs 1s 1s Note 6: Many of the family Typical Operating Characteristics are extremely similar. The extremes of these characteristics are found in the _21 (2.48V output) and the _41 (4.96V output). The Typical Operating Characteristics of the remainder of the family typically lie between those two extremes and can be estimated based on their output voltages. 1

11 Precision, Micropower, Low-Dropout, SC7 PIN NAME FUNCTION 1 IN Supply Voltage Input 2 OUT Reference Voltage Output 3 GND Ground Pin Description Detailed Description The family of precision bandgap references use a proprietary temperature coefficient curvature-correction circuit and laser-trimmed, thin-film resistors, resulting in a low temperature coefficient of less than 3ppm/ C and initial accuracy of better than.2%. These devices can source up to 1mA and sink up to 2µA with less than 2mV of dropout voltage, making them attractive for use in low-voltage applications. Applications Information Input Bypassing For the best line-transient performance, decouple the input with a.1µf ceramic capacitor as shown in the Typical Operating Circuit. Locate the capacitor as close to IN as possible. Output/Load Capacitance Devices in the family do not require an output capacitor for frequency stability. They are stable for capacitive loads from to 1µF. However, in applications where the load or the supply can experience step changes, an output capacitor reduces the amount of overshoot (or undershoot) and improves the circuit s transient response. Many applications do not need an external capacitor, and the can offer a significant advantage in these applications when board space is critical. Output Voltage Hysteresis Output voltage hysteresis is the change in the output voltage at before and after the device is cycled over its entire operating temperature range. Hysteresis is caused by differential package stress appearing across the bandgap core transistors. The typical temperature hysteresis value for the family is 1ppm. Turn-On Time These devices typically turn on and settle to within.1% of their final value in 85µs to 26µs depending on the device. The turn-on time can increase up to 1.25ms with the device operating at the minimum dropout voltage and the maximum load. 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 1LSB, 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. Supply Current The quiescent supply current of the series-mode family is typically 9µA and is virtually independent of the supply voltage, with only a 16µA/V (max) variation with supply voltage. When the supply voltage is below the minimum-specified input voltage (as during turn-on), the device can draw up to 5µA beyond the nominal supply current. The input-voltage source must be capable of providing this current to ensure reliable turn-on. 11

12 Precision, Micropower, Low-Dropout, SC7 TEMPERATURE COEFFICIENT (ppm/ C) 1, BIT 1 BIT 12 BIT 14 BIT 16 BIT 18 BIT 2 BIT OPERATING TEMPERATURE RANGE (T MAX - T MIN ) ( C) Figure 1. Temperature Coefficient vs. Operating Temperature Range for a 1LSB Maximum Error TRANSISTOR COUNT: 113 PROCESS: BiCMOS Chip Information 12

13 Precision, Micropower, Low-Dropout, SC7 Package Information SC7, 3L.EPS 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. Maxim Integrated Products, 12 San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.