MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference General Description The MAX6126 is an ultra-low-noise, high-precision, lowdropout voltage reference. This family of voltage references feature curvature-correction circuitry and high-stability, laser-trimmed, thin-film resistors that result in 3ppm/C (max) temperature coefficients and an excellent 0.02% (max) initial accuracy. The proprietary low-noise reference architecture produces a low flicker noise of 1.3VP-P and wideband noise as low as 60nV/Hz (2.048V output) without the increased supply current usually found in low-noise references. Improve wideband noise to 35nV/Hz and AC power-supply rejection by adding a 0.1F capacitor at the noise reduction pin. The MAX6126 series mode reference operates from a wide 2.7V to 12.6V supply voltage range and load-regulation specifications are guaranteed to be less than 0.025 for sink and source currents up to 10mA. These devices are available over the automotive temperature range of -40C to +125C. The MAX6126 typically draws 380A of supply current and is available in 2.048V, 2.500V, 2.800V, 3.000V, 4.096V, and 5.000V output voltages. These devices also feature dropout voltages as low as 200mV. Unlike conventional shunt-mode (two-terminal) references that waste supply current and require an external resistor, the MAX6126 offers supply current that is virtually independent of supply voltage and does not require an external resistor. The MAX6126 is stable with 0.1F to 10F of load capacitance. The MAX6126 is available in the tiny 8-pin MAX(R), as well as 8-pin SO packages. Features o Ultra-Low 1.3VP-P Noise (0.1Hz to 10Hz, 2.048V Output) o Ultra-Low 3ppm/C (max) Temperature Coefficient o 0.02% (max) Initial Accuracy o Wide (VOUT + 200mV) to 12.6V Supply Voltage Range o Low 200mV (max) Dropout Voltage o 380A Quiescent Supply Current o 10mA Sink/Source-Current Capability o Stable with CLOAD = 0.1F to 10F o Low 20ppm/1000hr Long-Term Stability o 0.025 (max) Load Regulation o 20V/V (max) Line Regulation o Force and Sense Outputs for Remote Sensing Pin Configuration TOP VIEW + NR 1 8 I.C.* IN 2 7 OUTF 3 6 OUTS GNDS 4 5 I.C.* MAX6126 Applications GND High-Resolution A/D and D/A Converters ATE Equipment High-Accuracy Reference Standard SO/MAX Precision Current Sources *I.C. = INTERNALLY CONNECTED. DO NOT USE. Digital Voltmeters High-Accuracy Industrial and Process Control MAX is a registered trademark of Maxim Integrated Products, Inc. PART MAX6126AASA21+ TEMP RANGE PINPACKAGE Ordering Information OUTPUT VOLTAGE (V) MAXIMUM INITIAL ACCURACY (%) MAXIMUM TEMPCO (-40C to +85C) (ppm/C) -40C to +125C 8 SO 2.048 0.02 3 MAX6126BASA21+ -40C to +125C 8 SO 2.048 0.06 5 MAX6126A21+ -40C to +125C 8 MAX 2.048 0.06 3 Ordering Information continued at end of data sheet. +Denotes a lead(Pb)-free/RoHS-compliant package. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maximintegrated.com. 19-2647; Rev 6; 8/12 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND) GNDS ....................................................................-0.3V to +0.3V IN ........................................................................... -0.3V to +13V OUTF, OUTS, NR........ -0.3V to the lesser of (VIN + 0.3V) or +6V Output Short Circuit to GND or IN ..........................................60s Continuous Power Dissipation (TA = +70C) 8-Pin MAX (derate 4.5mW/C above +70C) ............362mW 8-Pin SO (derate 5.88mW/C above +70C) ...............471mW Operating Temperature Range ........................-40C to +125C Junction Temperature .....................................................+150C Storage Temperature Range ............................-65C to +150C Lead Temperature (soldering, 10s) ................................+300C Soldering Temperature (reflow) ......................................+260C 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--MAX6126_21 (VOUT = 2.048V) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUTPUT Output Voltage VOUT TA = +25C Referred to VOUT, TA = +25C Output Voltage Accuracy TA = -40C to +85C Output Voltage Temperature Coefficient (Note 1) TCVOUT TA = -40C to +125C V A grade SO -0.02 +0.02 B grade SO -0.06 +0.06 A grade MAX -0.06 +0.06 B grade MAX -0.1 0.5 3 B grade SO 1 5 A grade MAX 1 3 B grade MAX 2 7 A grade SO 1 5 B grade SO 2 10 A grade MAX 2 5 B grade MAX 3 12 TA = +25C 2 20 VOUT/ VIN 2.7V VIN 12.6V Load Regulation VOUT/ IOUT Sourcing: 0 IOUT 10mA 0.7 25 Sinking: -10mA IOUT 0 1.3 25 Short to GND 160 Short to IN 20 SO 25 MAX 80 ISC Thermal Hysteresis (Note 2) VOUT/ cycle Long-Term Stability VOUT/ time TA = -40C to +125C 1000hr at TA = +25C % +0.1 A grade SO Line Regulation OUT Short-Circuit Current 2 2.048 40 SO 20 MAX 100 ppm/C V/V V/mA mA ppm ppm/ 1000hr Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_21 (VOUT = 2.048V) (continued) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DYNAMIC CHARACTERISTICS Noise Voltage Turn-On Settling Time Capacitive-Load Stability Range eOUT tR CLOAD f = 0.1Hz to 10Hz 1.3 f = 1kHz, CNR = 0 60 f = 1kHz, CNR = 0.1F 35 To VOUT = 0.01% of final value CNR = 0 0.8 CNR = 0.1F 20 No sustained oscillations VP-P nV/Hz ms 0.1 to 10 F INPUT Supply Voltage Range VIN Quiescent Supply Current IIN Guaranteed by line-regulation test 2.7 TA = +25C 12.6 380 TA = -40C to +125C 550 725 V A ELECTRICAL CHARACTERISTICS--MAX6126_25 (VOUT = 2.500V) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUTPUT Output Voltage VOUT TA = +25C Referred to VOUT, TA = +25C Output Voltage Accuracy TA = -40C to +85C Output Voltage Temperature Coefficient (Note 1) TCVOUT TA = -40C to +125C Line Regulation VOUT/ VIN Load Regulation VOUT/ IOUT Maxim Integrated 2.7V VIN 12.6V 2.500 V A grade SO -0.02 +0.02 B grade SO -0.06 +0.06 A grade MAX -0.06 +0.06 B grade MAX -0.1 % +0.1 A grade SO 0.5 3 B grade SO 1 5 A grade MAX 1 3 B grade MAX 2 7 A grade SO 1 5 B grade SO 2 10 A grade MAX 2 5 B grade MAX 3 12 TA = +25C 3 20 TA = -40C to +125C 40 Sourcing: 0 IOUT 10mA 1 25 Sinking: -10mA IOUT 0 1.8 25 ppm/C V/V V/mA 3 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_25 (VOUT = 2.500V) (continued) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER Dropout Voltage (Note 3) OUT Short-Circuit Current SYMBOL CONDITIONS VIN - VOUT VOUT = 0.1% ISC Thermal Hysteresis (Note 2) VOUT/ cycle Long-Term Stability VOUT/ time TYP MAX IOUT = 5mA MIN 0.06 0.2 IOUT = 10mA 0.12 0.4 Short to GND 160 Short to IN 20 SO 35 MAX 80 UNITS V mA ppm SO 20 MAX 100 ppm/ 1000hr f = 0.1Hz to 10Hz 1.45 VP-P f = 1kHz, CNR = 0 75 f = 1kHz, CNR = 0.1F 45 1000hr at TA = +25C DYNAMIC CHARACTERISTICS Noise Voltage Turn-On Settling Time Capacitive-Load Stability Range eOUT tR CLOAD To VOUT = 0.01% of final value CNR = 0 1 CNR = 0.1F 20 No sustained oscillations nV/Hz ms 0.1 to 10 F INPUT Supply Voltage Range VIN Quiescent Supply Current IIN Guaranteed by line-regulation test 2.7 TA = +25C 12.6 380 TA = -40C to +125C 550 725 V A ELECTRICAL CHARACTERISTICS--MAX6126_28 (VOUT = 2.800V) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDTIONS MIN TYP MAX UNITS OUTPUT Output Voltage VOUT Referred to VOUT, TA = +25C Output Voltage Accuracy Output Voltage Temperature Coefficient (Note 1) TA = +25C TA = -40C to +85C TCVOUT TA = -40C to +125C 2.800 A grade MAX -0.06 +0.06 B grade MAX -0.10 +0.10 A grade MAX VOUT/VIN Load Regulation VOUT/VIN Dropout Voltage (Note 3) 4 VIN - VOUT 3.0V VIN 12.6V 1 B grade MAX 2 7 2 5 B grade MAX 3 12 3.5 23 TA = -40C to +125C 45 Sourcing: 0 IOUT 10mA 1.3 28 Sinking: -10mA IOUT 0 2.4 28 IOUT = 5mA 0.06 0.2 IOUT = 10mA 0.12 0.4 VOUT = 0.1% % 3 A grade MAX TA = +25C Line Regulation V ppm/C V/V V/mA V Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_28 (VOUT = 2.800V) (continued) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER OUT Short-Circuit Current Thermal Hysteresis (Note 2) Long-Term Stability SYMBOL ISC CONDTIONS MIN 160 Short to IN 20 VOUT/cycle MAX VOUT/time TYP Short to GND MAX UNITS mA 80 ppm 100 ppm/ 1000hr f = 0.1Hz to 10Hz 1.45 VP-P f = 1kHz, CNR = 0 75 f = 1kHz, CNR = 0.1F 45 1000hr at TA = +25C MAX DYNAMIC CHARACTERISTICS Noise Voltage Turn-On Settling Time Capacitive-Load Stability Range eOUT tR CLOAD To VOUT = 0.01% of final value CNR = 0 1 CNR = 0.1F 20 No sustained oscillations nV/Hz ms 0.1 to 10 F INPUT Supply Voltage Range VIN Quiescent Supply Current IIN Guaranteed by line-regulation test 3.0 TA = +25C 12.6 380 TA = -40C to +125C 550 725 V A ELECTRICAL CHARACTERISTICS--MAX6126_30 (VOUT = 3.000V) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUTPUT Output Voltage VOUT TA = +25C Referred to VOUT, TA = +25C Output Voltage Accuracy TA = -40C to +85C Output Voltage Temperature Coefficient (Note 1) TCVOUT TA = -40C to +125C Maxim Integrated 3.000 V A grade SO -0.02 +0.02 B grade SO -0.06 +0.06 A grade MAX -0.06 +0.06 B grade MAX -0.1 % +0.1 A grade SO 0.5 3 B grade SO 1 5 A grade MAX 1 3 B grade MAX 2 7 A grade SO 1 5 B grade SO 2 10 A grade MAX 2 5 B grade MAX 3 12 ppm/C 5 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_30 (VOUT = 3.000V) (continued) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL Line Regulation VOUT/ VIN Load Regulation VOUT/ IOUT Dropout Voltage (Note 3) OUT Short-Circuit Current CONDITIONS 3.2V VIN 12.6V Thermal Hysteresis (Note 2) VOUT/ cycle Long-Term Stability VOUT/ time TYP MAX 4 25 TA = -40C to +125C 50 Sourcing: 0 IOUT 10mA 1.5 30 Sinking: -10mA IOUT 0 2.8 30 IOUT = 5mA 0.06 0.2 IOUT = 10mA 0.11 0.4 VIN - VOUT VOUT = 0.1% ISC MIN TA = +25C Short to GND 160 Short to IN 20 SO 20 MAX 80 UNITS V/V V/mA V mA ppm SO 20 MAX 100 ppm/ 1000hr f = 0.1Hz to 10Hz 1.75 VP-P f = 1kHz, CNR = 0 90 f = 1kHz, CNR = 0.1F 55 1000hr at TA = +25C DYNAMIC CHARACTERISTICS Noise Voltage Capacitive-Load Stability Range Turn-On Settling Time eOUT CLOAD tR No sustained oscillations To VOUT = 0.01% of final value nV/Hz 0.1 to 10 CNR = 0 1.2 CNR = 0.1F 20 F ms INPUT Supply Voltage Range Quiescent Supply Current VIN IIN Guaranteed by line-regulation test 3.2 TA = +25C 12.6 380 TA = -40C to +125C 550 725 V A ELECTRICAL CHARACTERISTICS--MAX6126_41 (VOUT = 4.096V) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUTPUT Output Voltage Output Voltage Accuracy 6 VOUT TA = +25C Referred to VOUT, TA = +25C 4.096 V A grade SO -0.02 +0.02 B grade SO -0.06 +0.06 A grade MAX -0.06 +0.06 B grade MAX -0.1 +0.1 % Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_41 (VOUT = 4.096V) (continued) (VIN = 5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS TA = -40C to +85C Output Voltage Temperature Coefficient (Note 1) TCVOUT TA = -40C to +125C Line Regulation VOUT/ VIN Load Regulation VOUT/ IOUT Dropout Voltage (Note 3) OUT Short-Circuit Current 4.3V VIN 12.6V Thermal Hysteresis (Note 2) VOUT/ cycle Long-Term Stability VOUT/ time TYP MAX A grade SO 0.5 3 B grade SO 1 5 A grade MAX 1 3 B grade MAX 2 7 A grade SO 1 5 B grade SO 2 10 A grade MAX 2 5 B grade MAX 3 12 TA = +25C 4.5 TA = -40C to +125C 30 60 Sourcing: 0 IOUT 10mA 2 40 Sinking: -10mA IOUT 0 5 40 VIN - VOUT VOUT = 0.1% ISC MIN IOUT = 5mA 0.05 0.2 IOUT = 10mA 0.1 0.4 Short to GND 160 Short to IN 20 SO 20 MAX 80 UNITS ppm/C V/V V/mA V mA ppm SO 20 MAX 100 ppm/ 1000hr f = 0.1Hz to 10Hz 2.4 VP-P f = 1kHz, CNR = 0 120 f = 1kHz, CNR = 0.1F 80 1000hr at TA = +25C DYNAMIC CHARACTERISTICS Noise Voltage Capacitive-Load Stability Range Turn-On Settling Time eOUT CLOAD tR No sustained oscillations To VOUT = 0.01% of final value nV/Hz 0.1 to 10 CNR = 0 1.6 CNR = 0.1F 20 F ms INPUT Supply Voltage Range VIN Quiescent Supply Current IIN Maxim Integrated Guaranteed by line-regulation test TA = +25C TA = -40C to +125C 4.3 12.6 380 550 725 V A 7 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_50 (VOUT = 5.000V) (VIN = 5.5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OUTPUT Output Voltage VOUT Output Voltage Accuracy TA = +25C TA = +25C TA = -40C to +85C Output Voltage Temperature Coefficient (Note 1) TCVOUT TA = -40C to +125C Line Regulation VOUT/ VIN Load Regulation VOUT/ IOUT Dropout Voltage (Note 3) OUT Short-Circuit Current 5.2V VIN 12.6V Thermal Hysteresis (Note 2) VOUT/ cycle Long-Term Stability VOUT/ time V A grade SO -0.02 +0.02 B grade SO -0.06 +0.06 A grade MAX -0.06 +0.06 B grade MAX -0.1 % +0.1 A grade SO 0.5 3 B grade SO 1 5 A grade MAX 1 3 B grade MAX 2 7 A grade SO 1 5 B grade SO 2 10 A grade MAX 2 5 B grade MAX 3 12 TA = +25C 3 40 TA = -40C to +125C 80 Sourcing: 0 IOUT 10mA 2.5 50 Sinking: -10mA IOUT 0 6.5 50 IOUT = 5mA 0.05 0.2 IOUT = 10mA 0.1 0.4 VIN - VOUT VOUT = 0.1% ISC 5.000 Short to GND 160 Short to IN 20 SO 15 MAX 80 ppm/C V/V V/mA V mA ppm SO 20 MAX 100 ppm/ 1000hr f = 0.1Hz to 10Hz 2.85 VP-P f = 1kHz, CNR = 0 145 f = 1kHz, CNR = 0.1F 95 1000hr at TA = +25C DYNAMIC CHARACTERISTICS Noise Voltage Capacitive-Load Stability Range 8 eOUT CLOAD No sustained oscillations 0.1 to 10 nV/Hz F Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference ELECTRICAL CHARACTERISTICS--MAX6126_50 (VOUT = 5.000V) (continued) (VIN = 5.5V, CLOAD = 0.1F, IOUT = 0, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25C.) PARAMETER SYMBOL Turn-On Settling Time CONDITIONS To VOUT = 0.01% of final value tR MIN TYP CNR = 0 2 CNR = 0.1F 20 MAX UNITS ms INPUT Supply Voltage Range VIN Quiescent Supply Current Guaranteed by line-regulation test 5.2 12.6 TA = +25C IIN 380 V 550 TA = -40C to +125C A 725 Note 1: Temperature coefficient is measured by the "box" method, i.e., the maximum VOUT / VOUT is divided by the maximum T. Note 2: Thermal hysteresis is defined as the change in +25C output voltage before and after cycling the device from TMAX to TMIN. Note 3: Dropout voltage is defined as the minimum differential voltage (VIN - VOUT) at which VOUT decreases by 0.1% from its original value at VIN = 5.0V (VIN = 5.5V for VOUT = 5.0V). Typical Operating Characteristics (VIN = 5V for MAX6126_21/25/30/41, VIN = 5.5V for MAX6126_50, CLOAD = 0.1F, IOUT = 0, TA = +25C, unless otherwise specified.) (Note 5) OUTPUT VOLTAGE (V) 2.0480 2.0475 2.0470 2.0485 2.0480 MAX6126 toc03 5.002 MAX6126 toc02 THREE TYPICAL PARTS OUTPUT VOLTAGE (V) THREE TYPICAL PARTS 2.0485 OUTPUT VOLTAGE (V) 2.0490 MAX6126 toc01 2.0490 MAX6126A_50 OUTPUT VOLTAGE TEMPERATURE DRIFT (VOUT = 5.000V) (SO) MAX6126A_21 OUTPUT VOLTAGE TEMPERATURE DRIFT (VOUT = 2.048V) (MAX) MAX6126A_21 OUTPUT VOLTAGE TEMPERATURE DRIFT (VOUT = 2.048V) (SO) THREE TYPICAL PARTS 5.001 5.000 4.999 2.0475 2.0465 2.0460 4.998 2.0470 -50 -25 0 25 50 75 TEMPERATURE (C) Maxim Integrated 100 125 -50 -25 0 25 50 75 TEMPERATURE (C) 100 125 -50 -25 0 25 50 75 100 125 TEMPERATURE (C) 9 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Typical Operating Characteristics (continued) (VIN = 5V for MAX6126_21/25/30/41, VIN = 5.5V for MAX6126_50, CLOAD = 0.1F, IOUT = 0, TA = +25C, unless otherwise specified.) (Note 5) MAX6126A_50 MAX6126_21 MAX6126_50 OUTPUT VOLTAGE TEMPERATURE DRIFT LOAD REGULATION LOAD REGULATION (VOUT = 5.000V) (MAX) 5.000 4.999 2.0475 TA = -40C 2.0470 MAX6126 toc06 TA = +25C 2.0480 TA = +25C 5.000 OUTPUT VOLTAGE (V) 5.001 5.001 MAX6126 toc05 2.0485 MAX6126 toc04 THREE TYPICAL PARTS OUTPUT VOLTAGE (V) OUTPUT VOLTAGE (V) 5.002 4.999 TA = -40C 4.998 TA = +125C 4.997 2.0465 TA = +125C 0 25 50 75 -10 10 5 0 10 5 MAX6126_25 DROPOUT VOLTAGE vs. SOURCE CURRENT MAX6126_50 DROPOUT VOLTAGE vs. SOURCE CURRENT MAX6126_21 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY DROPOUT VOLTAGE (mV) 100 TA = -40C 50 200 -20 -40 150 TA = +125C 100 TA = +25C TA = -40C -100 -120 0.001 0 3 6 9 12 15 0 -60 -80 50 0 0 MAX6126 toc09 250 MAX6126 toc07 TA = +25C 0 -5 OUTPUT CURRENT (mA) TA = +125C 150 0 OUTPUT CURRENT (mA) 250 200 -5 TEMPERATURE (C) 300 3 6 9 15 12 0.01 0.1 1 10 100 1000 SOURCE CURRENT (mA) SOURCE CURRENT (mA) FREQUENCY (kHz) MAX6126_50 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY MAX6126_21 SUPPLY CURRENT vs. INPUT VOLTAGE MAX6126_50 SUPPLY CURRENT vs. INPUT VOLTAGE -40 -60 -80 500 TA = +125C 400 TA = +25C TA = -40C 300 200 700 600 TA = +125C 500 TA = +25C 400 TA = -40C 300 200 100 -100 800 SUPPLY CURRENT (A) SUPPLY CURRENT (A) -20 900 MAX6126 toc12 600 MAX6126 toc10 0 MAX6126 toc11 DROPOUT VOLTAGE (mV) -10 125 100 PSRR (dB) -25 MAX6126 toc08 -50 PSRR (dB) 4.996 2.0460 4.998 100 -120 0.001 0 0.01 0.1 1 10 FREQUENCY (kHz) 10 100 1000 0 0 2 4 6 8 10 INPUT VOLTAGE (V) 12 14 0 2 4 6 8 10 12 14 INPUT VOLTAGE (V) Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Typical Operating Characteristics (continued) (VIN = 5V for MAX6126_21/25/30/41, VIN = 5.5V for MAX6126_50, CLOAD = 0.1F, IOUT = 0, TA = +25C, unless otherwise specified.) (Note 5) MAX6126_21 MAX6126_50 OUTPUT NOISE (0.1Hz TO 10Hz) OUTPUT NOISE (0.1Hz TO 10Hz) MAX6126 toc13 MAX6126 toc14 VOUT = 2.048V VOUT = 5V 0.4V/div 1V/div 1s/div 1s/div MAX6126_21 LOAD TRANSIENT MAX6126_21 LOAD TRANSIENT MAX6126 toc16 MAX6126 toc15 10mA 1mA IOUT 5mA/div IOUT 500A/div 0mA -100A VOUT AC-COUPLED 100mV/div VOUT AC-COUPLED 20mV/div 200s/div 200s/div CLOAD = 0.1F VIN = 5V CLOAD = 0.1F VIN = 5V IOUT = 0 TO 10mA VOUT = 2.048V IOUT = -100A TO 1mA VOUT = 2.048V MAX6126_21 LOAD TRANSIENT MAX6126_21 LOAD TRANSIENT MAX6126 toc18 MAX6126 toc17 10mA -1mA IOUT 5mA/div IOUT 5mA/div 0mA -10mA VOUT AC-COUPLED 20mV/div VOUT AC-COUPLED 100mV/div 1ms/div 400s/div CLOAD = 0.1F VIN = 5V Maxim Integrated IOUT = -1mA TO -10mA VOUT = 2.048V CLOAD = 10F VIN = 5V IOUT = 0 TO 10mA VOUT = 2.048V 11 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Typical Operating Characteristics (continued) (VIN = 5V for MAX6126_21/25/30/41, VIN = 5.5V for MAX6126_50, CLOAD = 0.1F, IOUT = 0, TA = +25C, unless otherwise specified.) (Note 5) MAX6126_21 MAX6126_21 LOAD TRANSIENT LOAD TRANSIENT MAX6126 toc20 MAX6126 toc19 +1mA IOUT 500A/div -1mA IOUT 5mA/div -100A -10mA VOUT AC-COUPLED 10mV/div VOUT AC-COUPLED 50mV/div 400s/div 1ms/div CLOAD = 10F VIN = 5V IOUT = -1mA TO -10mA VOUT = 2.048V CLOAD = 10F VIN = 5V IOUT = -100A TO 1mA VOUT = 2.048V MAX6126_50 LINE TRANSIENT MAX6126_21 LINE TRANSIENT MAX6126 toc22 MAX6126 toc21 3.2V 5.7V VIN 200mV/div VIN 200mV/div 2.7V 5.2V VOUT AC-COUPLED 20mV/div VOUT AC-COUPLED 10mV/div 400s/div 20s/div VOUT = 2.048V VIN = 5.2V TO 5.7V VOUT = 5V CLOAD = 0.1F CLOAD = 0.1F MAX6126_50 TURN-ON TRANSIENT MAX6126_21 TURN-ON TRANSIENT MAX6126 toc24 MAX6126 toc23 5.5V 5.5V VIN 2V/div VIN 2V/div GND GND VOUT 1V/div VOUT 2V/div GND 200s/div 20s/div CLOAD = 0.1F VOUT = 2.048V 12 CLOAD = 0.1F VOUT = 5V Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Typical Operating Characteristics (continued) (VIN = 5V for MAX6126_21/25/30/41, VIN = 5.5V for MAX6126_50, CLOAD = 0.1F, IOUT = 0, TA = +25C, unless otherwise specified.) (Note 5) MAX6126 toc25 MAX6126 toc26 2.5006 5.5V 2.5004 VIN 2V/div VIN 2V/div 2.5002 GND GND VOUT (V) 5.5V TWO TYPICAL PARTS VOUT = 2.5V 2.5000 2.4998 VOUT 2V/div VOUT 1V/div MAX6126 toc27 MAX6126B_25 LONG-TERM STABILITY vs. TIME (SO) MAX6126_50 TURN-ON TRANSIENT MAX6126_21 TURN-ON TRANSIENT 2.4996 GND 2.4994 0 400s/div 200 CLOAD = 10F VOUT = 5V CLOAD = 10F VOUT = 2.048V MAX6126B_25 LONG-TERM STABILITY vs. TIME (MAX) TWO TYPICAL PARTS VOUT = 5V 5.0004 800 1000 MAX6126B_50 LONG-TERM STABILITY vs. TIME (MAX) 5.0010 MAX6126 toc29 5.0006 600 TIME (hr) MAX6126B_50 LONG-TERM STABILITY vs. TIME (SO) MAX6126 toc28 2.5010 400 MAX6126 toc30 40s/div TWO TYPICAL PARTS VOUT = 5V 5.0005 2.5005 2.5000 VOUT (V) VOUT (V) VOUT (V) 5.0002 5.0000 5.0000 4.9998 4.9995 2.4995 4.9996 TWO TYPICAL PARTS VOUT = 2.5V 2.4990 4.9990 4.9994 0 200 400 600 TIME (hr) 800 1000 0 200 400 600 TIME (hr) 800 1000 0 200 400 600 800 1000 TIME (hr) Note 5: Many of the MAX6126 Typical Operating Characteristics are extremely similar. The extremes of these characteristics are found in the MAX6126_21 (2.048V output) and the MAX6126_50 (5.000V output). The Typical Operating Characteristics of the remainder of the MAX6126 family typically lie between those two extremes and can be estimated based on their output voltages. Maxim Integrated 13 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Pin Description (VOUT + 200mV) TO 12.6V INPUT PIN 1 NAME NR 2 IN 3 GND FUNCTION Noise Reduction. Connect a 0.1F capacitor to improve wideband noise. Leave unconnected if not used (see Figure 1). OUTF Positive Power-Supply Input Ground MAX6126 REFERENCE OUTPUT OUTS * 4 GNDS Ground-Sense Connection. Connect to ground connection at load. 5, 8 I.C. Internally Connected. Do not connect anything to these pins. 6 OUTS Voltage Reference Sense Output OUTF Voltage Reference Force Output. Short OUTF to OUTS as close to the load as possible. Bypass OUTF with a capacitor (0.1F to 10F) to GND. 7 IN NR 0.1F* GND GNDS *OPTIONAL. Figure 1. Noise-Reduction Capacitor Detailed Description Wideband Noise Reduction To improve wideband noise and transient power-supply noise, add a 0.1F capacitor to NR (Figure 1). Larger values do not improve noise appreciably. A 0.1F NR capacitor reduces the noise from 60nV/Hz to 35nV/Hz for the 2.048V output. Noise in the powersupply input can affect output noise, but can be reduced by adding an optional bypass capacitor between IN and GND, as shown in the Typical Operating Circuit. Output Bypassing The MAX6126 requires an output capacitor between 0.1F and 10F. Locate the output capacitor as close to OUTF as possible. For applications driving switching capacitive loads or rapidly changing load currents, it is advantageous to use a 10F capacitor in parallel with a 0.1F capacitor. Larger capacitor values reduce transients on the reference output. Supply Current The quiescent supply current of the series-mode MAX6126 family is typically 380A and is virtually independent of the supply voltage, with only a 2A/V (max) variation with supply voltage. When the supply voltage is below the minimum specified input voltage during turn-on, the device can draw 14 up to 300A beyond the nominal supply current. The input voltage source must be capable of providing this current to ensure reliable turn-on. Thermal Hysteresis Thermal hysteresis is the change of output voltage at TA = +25C before and after the device is cycled over its entire operating temperature range. The typical thermal hysteresis value is 20ppm (SO package). Turn-On Time These devices typically turn on and settle to within 0.1% of their final value in 200s to 2ms depending on the device. The turn-on time can increase up to 4ms with the device operating at the minimum dropout voltage and the maximum load. A noise reduction capacitor of 0.1F increases the turn-on time to 20ms. Output Force and Sense The MAX6126 provides independent connections for the power-circuit output (OUTF) supplying current into a load, and for the circuit input regulating the voltage applied to that load (OUTS). This configuration allows for the cancellation of the voltage drop on the lines connecting the MAX6126 and the load. When using the Kelvin connection made possible by the independent current and voltage connections, take the power connection to the load from OUTF, and bring a line from OUTS to join the line from OUTF, at the point where the voltage accu- Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference racy is needed. The MAX6126 has the same type of Kelvin connection to cancel drops in the ground return line. Connect the load to ground and bring a connection from GNDS to exactly the same point. IN ISOURCE Applications Information Precision Current Source Figure 2 shows a typical circuit providing a precision current source. The OUTF output provides the bias current for the bipolar transistor. OUTS and GNDS sense the voltage across the resistor and adjust the current sourced by OUTF accordingly. For even higher precision, use a MOSFET to eliminate base current errors. MAX6126 OUTF OUTS GND R GNDS High-Resolution DAC and Reference from a Single Supply VOUT(NOMINAL) / R = ISOURCE Figure 3 shows a typical circuit providing the reference for a high-resolution, 16-bit MAX541 D/A converter. Temperature Coefficient vs. Operating Temperature Range for a 1 LSB 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 4 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 (TMAX - TMIN) 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. Figure 2. Precision Current Source 3V SUPPLY VDD IN MAX6126 OUTF REF MAX541 DAC OUT ANALOG OUTPUT OUTS GND GNDS GND Figure 3. 14-Bit High-Resolution DAC and Positive Reference from a Single 3V Supply Maxim Integrated 15 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference 10,000 1000 100 8 BIT TEMPERATURE COEFFICIENT (ppm/C) 10 10 BIT 12 BIT 1 14 BIT 16 BIT 0.1 18 BIT 0.01 1 10 OPERATING TEMPERATURE RANGE (TMAX - TMIN) (C) 20 BIT 100 Figure 4. Temperature Coefficient vs. Operating Temperature Range for a 1 LSB Maximum Error Typical Operating Circuit Chip Information PROCESS: BiCMOS (VOUT + 200mV) TO 12.6V INPUT IN OUTF MAX6126 REFERENCE OUTPUT OUTS * NR LOAD * GND GNDS *OPTIONAL. 16 Maxim Integrated MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Ordering Information (continued) PART TEMP RANGE PINPACKAGE OUTPUT VOLTAGE (V) MAXIMUM INITIAL ACCURACY (%) MAXIMUM TEMPCO (-40C to +85C) (ppm/C) MAX6126B21+ -40C to +125C 8 MAX 2.048 0.1 7 MAX6126AASA25+ -40C to +125C 8 SO 2.500 0.02 3 MAX6126BASA25+ -40C to +125C 8 SO 2.500 0.06 5 MAX6126A25+ -40C to +125C 8 MAX 2.500 0.06 3 MAX6126B25+ -40C to +125C 8 MAX 2.500 0.1 7 MAX6126A28+ -40C to +125C 8 MAX 2.800 0.06 3 MAX6126B28+ -40C to +125C 8 MAX 2.800 0.1 7 MAX6126AASA30+ -40C to +125C 8 SO 3.000 0.02 3 MAX6126BASA30+ -40C to +125C 8 SO 3.000 0.06 5 MAX6126A30+ -40C to +125C 8 MAX 3.000 0.06 3 MAX6126B30+ -40C to +125C 8 MAX 3.000 0.1 7 MAX6126AASA41+ -40C to +125C 8 SO 4.096 0.02 3 MAX6126BASA41+ -40C to +125C 8 SO 4.096 0.06 5 MAX6126BASA41/V+ -40C to +125C 8 SO 4.096 0.06 5 MAX6126A41+ -40C to +125C 8 MAX 4.096 0.06 3 MAX6126B41+ -40C to +125C 8 MAX 4.096 0.1 7 MAX6126AASA50+ -40C to +125C 8 SO 5.000 0.02 3 MAX6126BASA50+ -40C to +125C 8 SO 5.000 0.06 5 MAX6126A50+ -40C to +125C 8 MAX 5.000 0.06 3 MAX6126B50+ -40C to +125C 8 MAX 5.000 0.1 7 +Denotes a lead(Pb)-free/RoHS-compliant package. /V denotes an automotive qualified part. Package Information (continued) For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 MAX U8+1 21-0036 90-0092 8 SO S8+4 21-0041 90-0096 Maxim Integrated 17 MAX6126 Ultra-High-Precision, Ultra-Low-Noise, Series Voltage Reference Revision History REVISION NUMBER REVISION DATE 0 10/02 Initial release 1 3/03 Remove "future product" and "contact factory" notes 1, 16 2 6/03 Add "A" grade devices 1, 16 3 12/03 Change MAX part number 1, 16 4 7/04 Add top mark to Ordering Information 1, 16 5 12/10 Add 2.8V option, add lead-free options, update Package Information 6 8/12 Added automotive package, MAX6126BASA41/V+ to data sheet DESCRIPTION PAGES CHANGED -- 1, 2, 4, 15, 16 17 Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. 18 ________________________________Maxim Integrated 160 Rio Robles, San Jose, CA 95134 USA 1-408-601-1000 (c) 2012 Maxim Integrated Products, Inc. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc.