FEATURES PIN CONFIGURATION Maximum temperature coefficient: 5 ppm/°C (B grade) Low long-term drift (LTD): 30 ppm (initial 1 khr typical) Initial output voltage error: ±0.1% (maximum) Operating temperature range: −40°C to +125°C Output current: +10 mA source/−3 mA sink Low quiescent current: 100 μA (maximum) Low dropout voltage: 250 mV at 2 mA Output voltage noise (0.1 Hz to 10 Hz): 29 μV p-p at 4.096 V (typical) Qualified for automotive applications ENABLE 1 GND SENSE 2 GND FORCE 3 ADR35xx TOP VIEW (Not to Scale) NC 4 8 VIN 7 VOUT SENSE 6 VOUT FORCE 5 NC NOTES 1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN. 09594-001 Data Sheet Micropower, High Accuracy Voltage References ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Figure 1. 8-Lead MSOP (RM-8 Suffix) APPLICATIONS Automotive battery monitors Portable instrumentation Process transmitters Remote sensors Medical instrumentation GENERAL DESCRIPTION The ADR3525W, ADR3530W, ADR3533W, ADR3540W, and ADR3550W are low cost, low power, high precision CMOS voltage references, featuring a maximum temperature coefficient (TC) of 5 ppm/°C (B grade), 8 ppm/°C (A grade), low operating current, and low output noise in an 8-lead MSOP package. For high accuracy, the output voltage and temperature coefficient are trimmed digitally during final assembly using the Analog Devices, Inc., patented DigiTrim® technology. Table 1. Selection Guide Model ADR3525W ADR3530W ADR3533W ADR3540W ADR3550W Output Voltage (V) 2.500 3.000 3.300 4.096 5.000 Input Voltage Range (V) 2.7 to 5.5 3.2 to 5.5 3.5 to 5.5 4.3 to 5.5 5.2 to 5.5 The low output voltage hysteresis and low long-term output voltage drift improve lifetime system accuracy. These CMOS references are available in five output voltages, all of which are specified over the automotive temperature range of −40°C to +125°C. Rev. 0 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. 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ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Terminology .................................................................................... 16 Applications ....................................................................................... 1 Theory of Operation ...................................................................... 17 Pin Configuration ............................................................................. 1 Long-Term Output Voltage Drift ............................................. 17 General Description ......................................................................... 1 Power Dissipation....................................................................... 17 Revision History ............................................................................... 2 Applications Information .............................................................. 18 Specifications..................................................................................... 3 Basic Voltage Reference Connection ....................................... 18 ADR3525 Electrical Characteristics .......................................... 3 Input and Output Capacitors .................................................... 18 ADR3530 Electrical Characteristics .......................................... 4 4-Wire Kelvin Connections ...................................................... 18 ADR3533 Electrical Characteristics .......................................... 5 VIN Slew Rate Considerations ................................................... 18 ADR3540 Electrical Characteristics .......................................... 6 Shutdown/Enable Feature ......................................................... 18 ADR3550 Electrical Characteristics .......................................... 7 Sample Applications ................................................................... 19 Absolute Maximum Ratings............................................................ 8 Outline Dimensions ....................................................................... 20 Thermal Resistance ...................................................................... 8 Ordering Guide .......................................................................... 20 ESD Caution .................................................................................. 8 Automotive Products ................................................................. 20 Pin Configuration and Function Descriptions ............................. 9 Typical Performance Characteristics ........................................... 10 REVISION HISTORY 9/11—Revision 0: Initial Version Rev. 0 | Page 2 of 20 Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 SPECIFICATIONS ADR3525 ELECTRICAL CHARACTERISTICS VIN = 2.7 V to 5.5 V, IL = 0 mA, TA = 25°C, unless otherwise noted. Table 2. Parameter OUTPUT VOLTAGE INITIAL OUTPUT VOLTAGE ERROR Symbol VOUT VOERR Conditions TEMPERATURE COEFFICIENT A Grade B Grade LINE REGULATION TCVOUT −40°C ≤ TA ≤ +125°C LOAD REGULATION Sourcing ΔVOUT/ΔVIN IL = 0 mA to 10 mA, VIN = 3.0 V, −40°C ≤ TA ≤ +125°C IL = 0 mA to −3 mA, VIN = 3.0 V, −40°C ≤ TA ≤ +125°C VIN = 3.0 V to 5.5 V VIN = 3.0 V to 5.5 V Unit V % mV 2.5 2.5 5 8 5 50 120 ppm/°C ppm/°C ppm/V ppm/V 10 30 ppm/mA 10 50 ppm/mA 10 −3 mA mA IQ VDO ENABLE PIN Shutdown Voltage ENABLE Voltage ENABLE Pin Leakage Current OUTPUT VOLTAGE NOISE VL VH IEN en p-p OUTPUT VOLTAGE NOISE DENSITY OUTPUT VOLTAGE HYSTERESIS 2 RIPPLE REJECTION RATIO LONG-TERM OUTPUT VOLTAGE DRIFT TURN-ON SETTLING TIME en ΔVOUT_HYS RRR ΔVOUT_LTD tR 2 Max 2.5025 ±0.1 ±2.5 IL Shutdown DROPOUT VOLTAGE 1 1 VIN = 2.7 V to 5.5 V VIN = 2.7 V to 5.5 V, −40°C ≤ TA ≤ +125°C Typ 2.500 ΔVOUT/ΔIL Sinking OUTPUT CURRENT CAPACITY Sourcing Sinking QUIESCENT CURRENT Normal Operation Min 2.4975 ENABLE ≥ VIN × 0.85 ENABLE = VIN, −40°C ≤ TA ≤ +125°C ENABLE ≤ 0.7 V IL = 0 mA, TA = −40°C ≤ TA ≤ +125°C IL = 2 mA, TA = −40°C ≤ TA ≤ +125°C 50 75 0 VIN × 0.85 ENABLE = VIN, TA = −40°C ≤ TA ≤ +125°C f = 0.1 Hz to 10 Hz f = 10 Hz to 10 kHz f = 1 kHz TA = +25°C to −40°C to +125°C to +25°C fIN = 60 Hz 1000 hours at 50°C CIN = 0.1 μF, CL = 0.1 μF, RL = 1 kΩ 1 18 42 1 70 −60 30 600 Refers to the minimum difference between VIN and VOUT such that VOUT maintains a minimum accuracy of 0.1%. See the Terminology section. See the Terminology section. The part is placed through the temperature cycle in the order of temperatures shown. Rev. 0 | Page 3 of 20 85 100 5 200 250 μA μA μA mV mV 0.7 VIN 3 V V μA μV p-p μV rms μV/√Hz ppm dB ppm μs ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet ADR3530 ELECTRICAL CHARACTERISTICS VIN = 3.2 V to 5.5 V, IL = 0 mA, TA = 25°C, unless otherwise noted. Table 3. Parameter OUTPUT VOLTAGE INITIAL OUTPUT VOLTAGE ERROR Symbol VOUT VOERR Conditions TEMPERATURE COEFFICIENT A Grade B Grade LINE REGULATION TCVOUT −40°C ≤ TA ≤ +125°C LOAD REGULATION Sourcing ΔVOUT/ΔVIN IL = 0 mA to 10 mA, VIN = 3.5 V, −40°C ≤ TA ≤ +125°C IL = 0 mA to −3 mA, VIN = 3.5 V, −40°C ≤ TA ≤ +125°C VIN = 3.5 V to 5.5 V VIN = 3.5 V to 5.5 V Unit V % mV 2.5 2.5 5 8 5 50 120 ppm/°C ppm/°C ppm/V ppm/V 9 30 ppm/mA 10 50 ppm/mA 10 −3 mA mA IQ VDO ENABLE PIN Shutdown Voltage ENABLE Voltage ENABLE Pin Leakage Current OUTPUT VOLTAGE NOISE VL VH IEN en p-p OUTPUT VOLTAGE NOISE DENSITY OUTPUT VOLTAGE HYSTERESIS 2 RIPPLE REJECTION RATIO LONG-TERM OUTPUT VOLTAGE DRIFT TURN-ON SETTLING TIME en ΔVOUT_HYS RRR ΔVOUT_LTD tR 2 Max 3.0030 ±0.1 ±3.0 IL Shutdown DROPOUT VOLTAGE 1 1 VIN = 3.2 V to 5.5 V VIN = 3.2 V to 5.5 V, −40°C ≤ TA ≤ +125°C Typ 3.0000 ΔVOUT/ΔIL Sinking OUTPUT CURRENT CAPACITY Sourcing Sinking QUIESCENT CURRENT Normal Operation Min 2.9970 ENABLE ≥ VIN × 0.85 ENABLE = VIN, −40°C ≤ TA ≤ +125°C ENABLE ≤ 0.7 V IL = 0 mA, TA = −40°C ≤ TA ≤ +125°C IL = 2 mA, TA = −40°C ≤ TA ≤ +125°C 50 75 0 VIN × 0.85 ENABLE = VIN, TA = −40°C ≤ TA ≤ +125°C f = 0.1 Hz to 10 Hz f = 10 Hz to 10 kHz f = 1 kHz TA = +25°C to −40°C to +125°C to +25°C fIN = 60 Hz 1000 hours at 50°C CIN = 0.1 μF, CL = 0.1 μF, RL = 1 kΩ 0.85 22 45 1.1 70 −60 30 700 Refers to the minimum difference between VIN and VOUT such that VOUT maintains a minimum accuracy of 0.1%. See the Terminology section. See the Terminology section. The part is placed through the temperature cycle in the order of temperatures shown. Rev. 0 | Page 4 of 20 85 100 5 200 250 μA μA μA mV mV 0.7 VIN 3 V V μA μV p-p μV rms μV/√Hz ppm dB ppm μs Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 ADR3533 ELECTRICAL CHARACTERISTICS VIN = 3.5 V to 5.5 V, IL = 0 mA, TA = 25°C, unless otherwise noted. Table 4. Parameter OUTPUT VOLTAGE INITIAL OUTPUT VOLTAGE ERROR Symbol VOUT VOERR Test Conditions/Comments TEMPERATURE COEFFICIENT A Grade B Grade LINE REGULATION TCVOUT −40°C ≤ TA ≤ +125°C LOAD REGULATION Sourcing ΔVOUT/ΔVIN IL = 0 mA to 10 mA, VIN = 3.8 V, −40°C ≤ TA ≤ +125°C IL = 0 mA to −3 mA, VIN = 3.8 V, −40°C ≤ TA ≤ +125°C VIN = 3.8 V to 5.5 V VIN = 3.8 V to 5.5 V Unit V % mV 2.5 2.5 5 8 5 50 120 ppm/°C ppm/°C ppm/V ppm/V 9 30 ppm/mA 10 50 ppm/mA 10 −3 mA mA IQ VDO ENABLE PIN Shutdown Voltage ENABLE Voltage ENABLE Pin Leakage Current OUTPUT VOLTAGE NOISE VL VH IEN en p-p OUTPUT VOLTAGE NOISE DENSITY OUTPUT VOLTAGE HYSTERESIS 2 RIPPLE REJECTION RATIO LONG-TERM OUTPUT VOLTAGE DRIFT TURN-ON SETTLING TIME en ΔVOUT_HYS RRR ΔVOUT_LTD tR 2 Max 3.3033 ±0.1 ±3.3 IL Shutdown DROPOUT VOLTAGE 1 1 VIN = 3.5 V to 5.5 V VIN = 3.5 V to 5.5 V, −40°C ≤ TA ≤ +125°C Typ 3.3000 ΔVOUT/ΔIL Sinking OUTPUT CURRENT CAPACITY Sourcing Sinking QUIESCENT CURRENT Normal Operation Min 3.2967 ENABLE ≥ VIN × 0.85 ENABLE = VIN, −40°C ≤ TA ≤ +125°C ENABLE ≤ 0.7 V IL = 0 mA, TA = −40°C ≤ TA ≤ +125°C IL = 2 mA, TA = −40°C ≤ TA ≤ +125°C 50 75 0 VIN × 0.85 ENABLE = VIN, TA = −40°C ≤ TA ≤ +125°C f = 0.1 Hz to 10 Hz f = 10 Hz to 10 kHz f = 1 kHz TA = +25°C to −40°C to +125°C to +25°C fIN = 60 Hz 1000 hours at 50°C CIN = 0.1 μF, CL = 0.1 μF, RL = 1 kΩ 0.85 25 46 1.2 70 −60 30 750 85 100 5 200 250 μA μA μA mV mV 0.7 VIN 3 V V μA μV p-p μV rms μV/√Hz ppm dB ppm μs Refers to the minimum difference between VIN and VOUT such that VOUT maintains a minimum accuracy of 0.1%. See the Terminology section. See the Terminology section. The part is placed through the temperature cycle in the order of temperatures shown. Rev. 0 | Page 5 of 20 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet ADR3540 ELECTRICAL CHARACTERISTICS VIN = 4.3 V to 5.5 V, IL = 0 mA, TA = 25°C, unless otherwise noted. Table 5. Parameter OUTPUT VOLTAGE INITIAL OUTPUT VOLTAGE ERROR Symbol VOUT VOERR Test Conditions/Comments TEMPERATURE COEFFICIENT A Grade B Grade LINE REGULATION TCVOUT −40°C ≤ TA ≤ +125°C LOAD REGULATION Sourcing ΔVOUT/ΔVIN IL = 0 mA to 10 mA, VIN = 4.6 V, −40°C ≤ TA ≤ +125°C IL = 0 mA to −3 mA, VIN = 4.6 V, −40°C ≤ TA ≤ +125°C VIN = 4.6 V to 5.5 V VIN = 4.6 V to 5.5 V Unit V % mV 2.5 2.5 3 8 5 50 120 ppm/°C ppm/°C ppm/V ppm/V 6 30 ppm/mA 15 50 ppm/mA 10 −3 mA mA IQ VDO ENABLE PIN Shutdown Voltage ENABLE Voltage ENABLE Pin Leakage Current OUTPUT VOLTAGE NOISE VL VH IEN en p-p OUTPUT VOLTAGE NOISE DENSITY OUTPUT VOLTAGE HYSTERESIS 2 RIPPLE REJECTION RATIO LONG-TERM OUTPUT VOLTAGE DRIFT TURN-ON SETTLING TIME en ΔVOUT_HYS RRR ΔVOUT_LTD tR 2 Max 4.1000 ±0.1 ±4.096 IL Shutdown DROPOUT VOLTAGE 1 1 VIN = 4.3 V to 5.5 V VIN = 4.3 V to 5.5 V, −40°C ≤ TA ≤ +125°C Typ 4.0960 ΔVOUT/ΔIL Sinking OUTPUT CURRENT CAPACITY Sourcing Sinking QUIESCENT CURRENT Normal Operation Min 4.0919 ENABLE ≥ VIN × 0.85 ENABLE = VIN, −40°C ≤ TA ≤ +125°C ENABLE ≤ 0.7 V IL = 0 mA, TA = −40°C ≤ TA ≤ +125°C IL = 2 mA, TA = −40°C ≤ TA ≤ +125°C 50 75 0 VIN × 0.85 ENABLE = VIN, TA = −40°C ≤ TA ≤ +125°C f = 0.1 Hz to 10 Hz f = 10 Hz to 10 kHz f = 1 kHz TA = +25°C to −40°C to +125°C to +25°C fIN = 60 Hz 1000 hours at 50°C CIN = 0.1 μF, CL = 0.1 μF, RL = 1 kΩ 0.85 29 53 1.4 70 −60 30 800 Refers to the minimum difference between VIN and VOUT such that VOUT maintains a minimum accuracy of 0.1%. See the Terminology section. See the Terminology section. The part is placed through the temperature cycle in the order of temperatures shown. Rev. 0 | Page 6 of 20 85 100 5 200 250 μA μA μA mV mV 0.7 VIN 3 V V μA μV p-p μV rms μV/√Hz ppm dB ppm μs Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 ADR3550 ELECTRICAL CHARACTERISTICS VIN = 5.2 V to 5.5 V, TA = 25°C, ILOAD = 0 mA, unless otherwise noted. Table 6. Parameter OUTPUT VOLTAGE INITIAL OUTPUT VOLTAGE ERROR Symbol VOUT VOERR Test Conditions/Comments TEMPERATURE COEFFICIENT A Grade B Grade LINE REGULATION TCVOUT −40°C ≤ TA ≤ +125°C LOAD REGULATION Sourcing ΔVOUT/ΔIL ΔVOUT/ΔVIN VIN = 5.5 V VIN = 5.5 V Max 5.005 ±0.1 ±5.0 Unit V % mV 2.5 2.5 3 8 5 50 120 ppm/°C ppm/°C ppm/V ppm/V 3 30 ppm/mA 19 50 ppm/mA 10 −3 mA mA IQ VDO ENABLE PIN Shutdown Voltage ENABLE Voltage ENABLE Pin Leakage Current OUTPUT VOLTAGE NOISE VL VH IEN en p-p OUTPUT VOLTAGE NOISE DENSITY OUTPUT VOLTAGE HYSTERESIS 2 RIPPLE REJECTION RATIO LONG-TERM OUTPUT VOLTAGE DRIFT TURN-ON SETTLING TIME en ΔVOUT_HYS RRR ΔVOUT_LTD tR 2 Typ 5.000 IL Shutdown DROPOUT VOLTAGE 1 1 VIN = 5.2 V to 5.5 V VIN = 5.2 V to 5.5 V, −40°C ≤ TA ≤ +125°C IL = 0 mA to 10 mA, VIN = 5.5 V, −40°C ≤ TA ≤ +125°C IL = 0 mA to −3 mA, VIN = 5.5 V, −40°C ≤ TA ≤ +125°C Sinking OUTPUT CURRENT CAPACITY Sourcing Sinking QUIESCENT CURRENT Normal Operation Min 4.995 ENABLE > VIN × 0.85 ENABLE = VIN, −40°C ≤ TA ≤ +125°C ENABLE < 0.7 V IL = 0 mA, −40°C ≤ TA ≤ +125°C IL = 2 mA, −40°C ≤ TA ≤ +125°C 50 75 0 VIN × 0.85 ENABLE = VIN, −40°C ≤ TA ≤ +125°C f = 0.1 Hz to 10 Hz f = 10 Hz to 10 kHz f = 1 kHz TA = +25°C to −40°C to +125°C to +25°C fIN = 60 Hz 1000 hours at 50°C CIN = 0.1 μF, CL = 0.1 μF, RL = 1 kΩ 0.85 35 60 1.5 70 −58 30 900 Refers to the minimum difference between VIN and VOUT such that VOUT maintains a minimum accuracy of 0.1%. See the Terminology section. See the Terminology section. The part is placed through the temperature cycle in the order of temperatures shown. Rev. 0 | Page 7 of 20 85 100 5 200 250 μA μA μA mV mV 0.7 VIN 3 V V μA μV p-p μV rms μV/√Hz ppm dB ppm μs ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet ABSOLUTE MAXIMUM RATINGS TA = 25°C, unless otherwise noted. THERMAL RESISTANCE Table 7. θJA is specified for the worst-case conditions, that is, a device soldered in a circuit board for surface-mount packages. Parameter Supply Voltage ENABLE to GND SENSE Voltage Operating Temperature Range Storage Temperature Range Junction Temperature Range Rating 6V VIN −40°C to +125°C −65°C to +150°C −65°C to +150°C Table 8. Thermal Resistance Package Type 8-Lead MSOP (RM-8 Suffix) 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. ESD CAUTION Rev. 0 | Page 8 of 20 θJA 132.5 θJC 43.9 Unit °C/W Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 ENABLE 1 GND SENSE 2 GND FORCE 3 ADR35xx TOP VIEW (Not to Scale) NC 4 8 VIN 7 VOUT SENSE 6 VOUT FORCE 5 NC NOTES 1. NC = NO CONNECT. DO NOT CONNECT TO THIS PIN. 09594-002 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Figure 2. Pin Configuration Table 9. Pin Function Descriptions Pin No. 1 2 3 4 5 6 7 8 Mnemonic ENABLE GND SENSE GND FORCE NC NC VOUT FORCE VOUT SENSE VIN Description Enable Connection. Enables or disables the device. Ground Voltage Sense Connection. Connect directly to the point of lowest potential in the application. Ground Force Connection. No Connect. Do not connect to this pin. No Connect. Do not connect to this pin. Reference Voltage Output. Reference Voltage Output Sensing Connection. Connect directly to the voltage input of the load devices. Input Voltage Connection. Rev. 0 | Page 9 of 20 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, unless otherwise noted. 2.5008 5.0010 OUTPUT VOLTAGE (V) 5.0015 2.5004 2.5002 2.5000 2.4998 2.4996 5.0005 5.0000 4.9995 4.9990 4.9985 2.4992 4.9980 2.4990 –40 –25 –10 5 20 35 50 65 80 95 110 125 TEMPERATURE (ºC) 09594-003 2.4994 4.9975 –40 –25 –10 5 20 35 50 65 80 95 110 125 TEMPERATURE (ºC) Figure 3. ADR3525 Output Voltage vs. Temperature Figure 6. ADR3550 Output Voltage vs. Temperature 45 40 40 35 35 25 20 15 30 25 20 15 10 10 5 5 0 1 2 3 4 5 6 7 8 9 TEMPERATURE COEFFICIENT (ppm/°C) 10 11 0 09594-004 0 0 1 2 3 4 5 6 7 8 9 10 11 TEMPERATURE COEFFICIENT (ppm/°C) Figure 4. ADR3525 Temperature Coefficient Distribution 09594-007 NUMBER OF DEVICES 30 Figure 7. ADR3550 Temperature Coefficient Distribution 24 35 ADR3525 ADR3530 ADR3533 ADR3540 ADR3550 20 18 ADR3525 ADR3530 ADR3533 ADR3540 ADR3550 IL = 0mA TO 10mA SOURCING 30 LOAD REGULATION (ppm/V) 22 16 14 12 10 8 6 4 IL = 0mA TO –3mA SINKING 25 20 15 10 2 –25 –10 5 20 35 50 65 TEMPERATURE (°C) 80 95 110 125 5 –40 09594-005 0 –40 Figure 5. Load Regulation vs. Temperature (Sourcing) –25 –10 5 20 35 50 65 TEMPERATURE (°C) 80 95 110 Figure 8. Load Regulation vs. Temperature (Sinking) Rev. 0 | Page 10 of 20 125 09594-008 NUMBER OF DEVICES VIN = 5.5V 5.0020 2.5006 LOAD REGULATION (ppm/V) OUTPUT VOLTAGE (V) 5.0025 VIN = 5.5V 09594-006 2.5010 Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 400 –40°C +25°C +125°C 300 250 1 200 150 10µV/DIV 100 50 TIME = 1s/DIV –2 –1 0 1 2 3 4 5 6 7 8 9 10 LOAD CURRENT (mA) CH1 pk-pk = 18µV 09594-009 0 –3 Figure 9. ADR3525 Dropout Voltage vs. Load Current CH1 RMS = 3.14µV 09594-012 DIFFERENTIAL VOLTAGE (mV) 350 Figure 12. ADR3525 Output Voltage Noise (0.1 Hz to 10 Hz) 350 –40°C +25°C +125°C DIFFERENTIAL VOLTAGE (mV) 300 250 200 1 150 100 100µV/DIV –2 –1 0 1 2 3 4 5 6 7 8 9 10 LOAD CURRENT (mA) 09594-010 TIME = 1s/DIV CH1 pk-pk = 300µV Figure 10. ADR3550 Dropout Voltage vs. Load Current Figure 13. ADR3525 Output Voltage Noise (10 Hz to 10 kHz) 12 140 10 NOISE DENSITY (µV p-p/ Hz) 100 ADR3525 ADR3530 ADR3533 ADR3540 ADR3550 80 60 40 8 6 4 2 20 0 –40 –25 –10 5 20 35 50 65 80 95 TEMPERATURE (°C) 110 125 0 0.1 09594-011 LINE REGULATION (ppm/V) 120 CH1 RMS = 42.0µV 1 10 100 1k FREQUENCY (Hz) Figure 14. ADR3525 Output Noise Spectral Density Figure 11. Line Regulation vs. Temperature Rev. 0 | Page 11 of 20 10k 09594-014 0 –3 09594-013 50 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet CL = 1.1µF CIN = 0.1µF –10 –20 –30 –40 1 –50 –60 10µV/DIV –70 10 100 1k 10k 100k FREQUENCY (Hz) CH1 pk-pk = 33.4µV Figure 15. ADR3525 Ripple Rejection Ratio vs. Frequency CH1 RMS = 5.68µV 09594-018 –90 09594-015 –80 Figure 18. ADR3550 Output Voltage Noise (0.1 Hz to 10 Hz) CIN = CL = 0.1µF RL = ∞ 1 VIN = 2V/DIV 1 09594-016 VOUT = 1V/DIV CH1 pk-pk = 446µV Figure 16. ADR3525 Start-Up Response CH1 RMS = 60.3µV 09594-019 100µV/DIV TIME = 200µs/DIV 2 Figure 19. ADR3550 Output Voltage Noise (10 Hz to 10 kHz) 12 10 VENABLE = 1V/DIV VIN = 3.0V CIN = CL = 0.1µF RL = ∞ NOISE DENSITY (µV p-p/ Hz) 1 VOUT = 1V/DIV TIME = 200µs/DIV 2 8 6 4 2 0 0.1 1 10 100 1k FREQUENCY (Hz) Figure 17. ADR3525 Restart Response from Shutdown Figure 20. ADR3550 Output Noise Spectral Density Rev. 0 | Page 12 of 20 10k 09594-020 ENABLE 09594-017 RIPPLE REJECTION RATIO (dB VOUT/VIN) 0 Data Sheet CL = 1.1µF CIN = 0.1µF –10 ENABLE 1V/DIV –20 CIN = CL = 0.1µF VIN = 3V RL = 1kΩ –30 –40 1 –50 –60 2 –90 10 100 1k 10k 100k FREQUENCY (Hz) VOUT = 1V/DIV TIME = 200µs/DIV 09594-021 –80 09594-024 –70 Figure 24. ADR3525 Shutdown Response Figure 21. ADR3550 Ripple Rejection Ratio vs. Frequency 3.2V CIN = 0µF CL = 0.1µF RL = ∞ VIN 2V/DIV 2.7V 500mV/DIV CIN = CL = 0.1µF 1 2 VOUT = 10mV/DIV VOUT 2V/DIV 09594-022 09594-025 TIME = 200µs/DIV 2 TIME = 1ms/DIV 1 Figure 22. ADR3550 Start-Up Response Figure 25. ADR3525 Line Transient Response SOURCING IL ENABLE 1 +10mA SINKING SINKING VENABLE = 2V/DIV VIN = 5.5V CIN = CL = 0.1µF RL = ∞ –3mA CIN = 0.1µF CL = 0.1µF RL = 250Ω VOUT = 2V/DIV 2.5V 2 TIME = 1ms/DIV Figure 26. ADR3525 Load Transient Response Figure 23. ADR3550 Restart Response from Shutdown Rev. 0 | Page 13 of 20 09594-026 VOUT = 20mV/DIV TIME = 200µs/DIV 09594-023 RIPPLE REJECTION RATIO (dB VOUT/VIN) 0 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet 100 VIN = 5.5 V 90 SUPPLY CURRENT (µA) 80 ENABLE 2V/DIV CIN = CL = 0.1µF VIN = 5V RL = 1kΩ 1 70 60 50 40 30 20 TIME = 200µs/DIV 0 –40 –25 –10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) Figure 27. ADR3550 Shutdown Response 09594-030 VOUT = 2V/DIV 09594-027 10 2 Figure 30. Supply Current vs. Temperature 2.0 –40°C +25°C +125°C 1.8 VIN = 100mV/DIV 1.6 SUPPLY CURRENT (mA) 5.5V CIN = CL = 0.1µF 1 5.2V 1.4 1.2 1.0 0.8 0.6 0.4 VOUT = 5mV/DIV 0 09594-028 TIME = 1ms/DIV 0 OUTPUT IMPEDANCE (Ω) +10mA SINKING SINKING 30 40 50 60 70 80 90 100 Figure 31. Supply Current vs. ENABLE Pin Voltage 10 SOURCING 20 ENABLE VOLTAGE (% of V IN) Figure 28. ADR3550 Line Transient Response IL 10 09594-031 0.2 2 –3mA CIN = 0.1µF CL = 0.1µF RL = 500Ω CL = 0.1µF CL = 1.1µF 1 0.1 VOUT = 20mV/DIV 0.01 0.01 09594-029 TIME = 1ms/DIV 0.1 1 10 100 1k FREQUENCY (Hz) Figure 32. ADR3550 Output Impedance vs. Frequency Figure 29. ADR3550 Load Transient Response Rev. 0 | Page 14 of 20 10k 09594-032 5.0V Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 80 8 NUMBER OF DEVICES 7 6 5 4 3 2 0.020 Figure 33. Output Voltage Drift Distribution After Reflow (SHR Drift) TA = +25°C → –40°C → +125°C → +25°C 7 6 5 4 3 2 1 40 09594-034 OUTPUT VOLTAGE HYSTERESIS (ppm) 20 30 10 –10 0 –20 –40 –30 –50 –70 –60 –80 –100 –90 –110 –130 –120 0 –140 0 –20 –40 –60 0 200 400 600 800 1000 Figure 35. ADR3550 Typical Long-Term Output Voltage Drift (Four Devices, 1000 Hours) 8 –150 20 ELAPSED TIME (Hours) 09594-033 0.018 0.016 0.014 0.012 0.010 0.008 0.006 0.004 0 RELATIVE SHIFT IN VOUT (%) NUMBER OF DEVICES 40 –80 0.002 –0.002 –0.004 –0.006 –0.008 0 –0.010 1 60 Figure 34. ADR3550 Thermally Induced Output Voltage Hysteresis Distribution Rev. 0 | Page 15 of 20 09594-035 LONG-TERM OUTPUT VOLTAGE DRIFT (ppm) 9 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet TERMINOLOGY Dropout Voltage (VDO) Dropout voltage, sometimes referred to as supply voltage headroom or supply-output voltage differential, is defined as the minimum voltage differential between the input and output such that the output voltage is maintained to within 0.1% accuracy. Long-Term Output Voltage Drift (ΔVOUT_LTD) Long-term output voltage drift refers to the shift in output voltage after 1000 hours of operation in a constant 50°C environment. This is expressed as either a shift in voltage or a difference in ppm from the nominal output. ΔVOUT _ LTD = VOUT (t 1 ) − VOUT (t 0 ) [V] VDO = (VIN − VOUT)min | IL = constant Because the dropout voltage depends upon the current passing through the device, it is always specified for a given load current. In series-mode devices, dropout voltage typically increases proportionally to load current (see Figure 9 and Figure 10). Temperature Coefficient (TCVOUT) The temperature coefficient relates the change in output voltage to the change in ambient temperature of the device, as normalized by the output voltage at 25°C. This parameter is expressed in ppm/°C and can be determined by the following equations: TCVOUT 1 = max{VOUT (T1 , T2 )} − min{VOUT (T1 , T2 )} VOUT (T2 ) × (T2 − T1 ) × max{VOUT (T2 ,T3 )} − min{VOUT (T2 ,T3 )} VOUT (T2 ) × (T3 − T2 ) × 106 [ ppm / °C ] TCVOUT = max{TCVOUT1 ,TCVOUT 2 } (1) where: VOUT(T) is the output voltage at Temperature T. T1 = −40°C. T2 = +25°C. T3 = +125°C. Solder Heat Resistance (SHR) Drift SHR drift refers to the permanent shift in output voltage induced by exposure to reflow soldering, expressed in units of ppm. This is caused by changes in the stress exhibited upon the die by the package materials when exposed to high temperatures. This effect is more pronounced in lead-free soldering processes due to higher reflow temperatures. ΔVOUT _ HYS = VOUT (25°C ) − VOUT _ TC [V] VOUT (25°C ) × 106 [ppm] Line Regulation Line regulation refers to the change in output voltage in response to a given change in input voltage and is expressed in percent per volt, ppm per volt, or microvolts per volt change in input voltage. This parameter accounts for the effects of self-heating. Thermally Induced Output Voltage Hysteresis (ΔVOUT_HYS) Thermally induced output voltage hysteresis represents the change in output voltage after the device is exposed to a specified temperature cycle. This is expressed as either a shift in voltage or a difference in ppm from the nominal output. VOUT (25°C ) − VOUT _ TC VOUT (t 0 ) where: VOUT(t0) is the VOUT at 50°C at Time 0. VOUT(t1) is the VOUT at 50°C after 1000 hours of operation at 50°C. This three-point method ensures that TCVOUT accurately portrays the maximum difference between any of the three temperatures at which the output voltage of the part is measured. ΔVOUT _ HYS = VOUT (t 1 ) −VOUT (t 0 ) Load Regulation Load regulation refers to the change in output voltage in response to a given change in load current and is expressed in microvolts per mA, ppm per mA, or ohms of dc output resistance. This parameter accounts for the effects of selfheating. 106 [ ppm / °C ] TCVOUT 2 = ΔVOUT _ LTD = × 10 6 [ppm] where: VOUT(25°C) is the output voltage at 25°C. VOUT_TC is the output voltage after temperature cycling. Rev. 0 | Page 16 of 20 Data Sheet ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 THEORY OF OPERATION VIN ENABLE BAND GAP VOLTAGE REFERENCE LONG-TERM OUTPUT VOLTAGE DRIFT VBG VOUT FORCE VOUT SENSE RFB1 GND FORCE 09594-036 RFB2 GND SENSE Figure 36. Block Diagram The ADR3525W/ADR3530W/ADR3533W/ADR3540W/ ADR3550W use a patented voltage reference architecture to achieve high accuracy, low temperature coefficient (TC), and low noise in a CMOS process. Like all band gap references, the references combine two voltages of opposite TCs to create an output voltage that is nearly independent of ambient temperature. However, unlike traditional band gap voltage references, the temperature-independent voltage of the references is arranged to be the base-emitter voltage, VBE, of a bipolar transistor at room temperature rather than the VBE extrapolated to 0 K (the VBE of bipolar transistor at 0 K is approximately VG0, the band gap voltage of silicon). A corresponding positive TC voltage is then added to the VBE voltage to compensate for its negative TC. The key benefit of this technique is that the trimming of the initial accuracy and TC can be performed without interfering with one another, thereby increasing overall accuracy across temperature. Curvature correction techniques further reduce the temperature variation. The band gap voltage (VBG) is then buffered and amplified to produce stable output voltages of 2.5 V and 5.0 V. The output buffer can source up to 10 mA and sink up to −3 mA of load current. The ADR35xx references leverage Analog Devices patented DigiTrim technology to achieve high initial accuracy and low TC, and precision layout techniques lead to very low long-term drift and thermal hysteresis. One of the key parameters of the ADR35xx references is longterm output voltage drift. Independent of the output voltage model and in a 50°C environment, these devices exhibit a typical drift of approximately 30 ppm after 1000 hours of continuous, unloaded operation. It is important to understand that long-term output voltage drift is not tested or guaranteed by design and that the output from the device may shift beyond the typical 30 ppm specification. Because most of the drift occurs in the first 200 hours of device operation, burning in the system board with the reference mounted can reduce subsequent output voltage drift over time. See the AN-713 Application Note, The Effect of Long-Term Drift on Voltage References, at www.analog.com for more information regarding the effects of long-term drift and how it can be minimized. POWER DISSIPATION The ADR35xx voltage references are capable of sourcing up to 10 mA of load current at room temperature across the rated input voltage range. However, when used in applications subject to high ambient temperatures, the input voltage and load current should be carefully monitored to ensure that the device does not exceed its maximum power dissipation rating. The maximum power dissipation of the device can be calculated via the following equation: PD TJ TA JA [W ] where: PD is the device power dissipation. TJ is the device junction temperature. TA is the ambient temperature. θJA is the package (junction-to-air) thermal resistance. Because of this relationship, the acceptable load current in high temperature conditions may be less than the maximum currentsourcing capability of the device. In no case should the part be operated outside of its maximum power rating because doing so can result in premature failure or permanent damage to the device. Rev. 0 | Page 17 of 20 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet APPLICATIONS INFORMATION BASIC VOLTAGE REFERENCE CONNECTION 1µF 0.1µF 8 VIN VOUT FORCE 6 1 ENABLE VOUT SENSE 7 AD3525/ADR3530/ ARD3533/ADR3540/ ADR3550 VOUT 2.5V 0.1µF 09594-037 GND SENSE 2 GND FORCE 3 voltages can be sensed accurately. These voltages are fed back into the internal amplifier and used to automatically correct for the voltage drop across the current-carrying output and ground lines, resulting in a highly accurate output voltage across the load. To achieve the best performance, the sense connections should be connected directly to the point in the load where the output voltage should be the most accurate. See Figure 38 for an example application. OUTPUT CAPACITOR(S) SHOULD BE MOUNTED AS CLOSE TO VOUT FORCE PIN AS POSSIBLE. Figure 37. Basic Reference Connection The circuit shown in Figure 37 illustrates the basic configuration for the ADR35xx references. Bypass capacitors should be connected according to the following guidelines. 0.1µF VIN INPUT AND OUTPUT CAPACITORS A 1 μF to 10 μF electrolytic or ceramic capacitor can be connected to the input to improve transient response in applications where the supply voltage may fluctuate. An additional 0.1 μF ceramic capacitor should be connected in parallel to reduce high frequency supply noise. 1µF 0.1µF 8 V IN VOUT FORCE 6 1 ENABLE VOUT SENSE 7 AD3525/ADR3530/ ARD3533/ADR3540/ ADR3550 LOAD SENSE CONNECTIONS SHOULD CONNECT AS CLOSE TO LOAD DEVICE AS POSSIBLE. GND SENSE 2 GND FORCE 3 09594-038 VIN 2.7V TO 5.5V Figure 38. Application Showing Kelvin Connection A ceramic capacitor of at least a 0.1 μF must be connected to the output to improve stability and help filter out high frequency noise. An additional 1 μF to 10 μF electrolytic or ceramic capacitor can be added in parallel to improve transient performance in response to sudden changes in load current; however, the designer should keep in mind that doing so increases the turn-on time of the device. Best performance and stability is attained with low ESR (for example, less than 1 Ω), low inductance ceramic chip-type output capacitors (X5R, X7R, or similar). If using an electrolytic capacitor on the output, a 0.1 μF ceramic capacitor should be placed in parallel to reduce overall ESR on the output. 4-WIRE KELVIN CONNECTIONS Current flowing through a PCB trace produces an IR voltage drop, and with longer traces, this drop can reach several millivolts or more, introducing a considerable error into the output voltage of the reference. A 1 inch long, 5 millimeter wide trace of 1 ounce copper has a resistance of approximately 100 mΩ at room temperature; at a load current of 10 mA, this can introduce a full millivolt of error. In an ideal board layout, the reference should be mounted as close to the load as possible to minimize the length of the output traces, and, therefore, the error introduced by voltage drop. However, in applications where this is not possible or convenient, force and sense connections (sometimes referred to as Kelvin sensing connections) are provided as a means of minimizing the IR drop and improving accuracy. Kelvin connections work by providing a set of high impedance voltage-sensing lines to the output and ground nodes. Because very little current flows through these connections, the IR drop across their traces is negligible, and the output and ground It is always advantageous to use Kelvin connections whenever possible. However, in applications where the IR drop is negligible or an extra set of traces cannot be routed to the load, the force and sense pins for both VOUT and GND can simply be tied together, and the device can be used in the same way as a normal 3-terminal reference (as shown in Figure 37). VIN SLEW RATE CONSIDERATIONS In applications with slow rising input voltage signals, the reference exhibits overshoot or other transient anomalies that appear on the output. These phenomena also appear during shutdown as the internal circuitry loses power. To avoid such conditions, ensure that the input voltage waveform has both a rising and falling slew rate of at least 0.1 V/ms. SHUTDOWN/ENABLE FEATURE The ADR35xx references can be switched to a low power shutdown mode when a voltage of 0.7 V or lower is input to the ENABLE pin. Likewise, the reference becomes operational for ENABLE voltages of 0.85 × VIN or higher. During shutdown, the supply current drops to less than 5 μA, useful in applications that are sensitive to power consumption. If using the shutdown feature, ensure that the ENABLE pin voltage does not fall between 0.7 V and 0.85 × VIN because this causes a large increase in the supply current of the device and may keep the reference from starting up correctly (see Figure 31). If not using the shutdown feature, however, the ENABLE pin can simply be tied to the VIN pin, and the reference remains operational continuously. Rev. 0 | Page 18 of 20 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 SAMPLE APPLICATIONS VIN 8 V IN Negative Reference +5V VOUT FORCE 6 R1 10kΩ 1 ENABLE V 7 OUT SENSE Figure 39 shows how to connect the ADR3550 and a standard CMOS op amp, such as the AD8663, to provide a negative reference voltage. This configuration provides two main advantages: first, it requires only two devices and, therefore, does not require excessive board space; second, and more importantly, it does not require any external resistors, meaning that the performance of this circuit does not rely on choosing expensive parts with low temperature coefficients to ensure accuracy. 1µF 0.1µF ADR3550 0.1µF R2 10kΩ GND SENSE 2 GND FORCE 3 +15V –5V ADA4000-1 R3 5kΩ 09594-040 Data Sheet –15V +VDD Figure 40. ADR3550 Bipolar Output Reference 8 VIN 1 ENABLE VOUT SENSE 7 AD8663 VOUT FORCE 6 ADR3550 GND SENSE 2 Boosted Output Current Reference –5V 0.1µF –VDD GND FORCE 3 0.1µF Figure 39. ADR3550 Negative Reference In this configuration, the VOUT FORCE and VOUT SENSE pins of the reference sit at virtual ground, and the negative reference voltage and load current are taken directly from the output of the operational amplifier. Note that in applications where the negative supply voltage is close to the reference output voltage, a dual-supply, low offset, rail-to-rail output amplifier must be used to ensure an accurate output voltage. The operational amplifier must also be able to source or sink an appropriate amount of current for the application. Figure 41 shows a configuration for obtaining higher current drive capability from the ADR35xx references without sacrificing accuracy. The op amp regulates the current flow through the MOSFET until VOUT equals the output voltage of the reference; current is then drawn directly from VIN instead of from the reference itself, allowing increased current drive capability. VIN +16V U6 8 1 1µF 0.1µF Bipolar Output Reference VIN VOUT FORCE 6 ENABLE VOUT SENSE 7 AD3525/ADR3530/ ARD3533/ADR3540/ ADR3550 R1 100Ω 2N7002 AD8663 VOUT 0.1µF RL 200Ω CL 0.1µF GND SENSE 2 Figure 40 shows a bipolar reference configuration. By connecting the output of the ADR3550 to the inverting terminal of an operational amplifier, it is possible to obtain both positive and negative reference voltages. R1 and R2 must be matched as closely as possible to ensure minimal difference between the negative and positive outputs. Resistors with low temperature coefficients must also be used if the circuit is used in environments with large temperature swings; otherwise, a voltage difference develops between the two outputs as the ambient temperature changes. GND FORCE 3 09594-041 0.1µF 09594-039 1µF Figure 41. Boosted Output Current Reference Because the current-sourcing capability of this circuit depends only on the ID rating of the MOSFET, the output drive capability can be adjusted to the application simply by choosing an appropriate MOSFET. In all cases, the VOUT SENSE pin should be tied directly to the load device to maintain maximum output voltage accuracy. Rev. 0 | Page 19 of 20 ADR3525/ADR3530/ADR3533/ADR3540/ADR3550 Data Sheet OUTLINE DIMENSIONS 3.20 3.00 2.80 3.20 3.00 2.80 8 1 5.15 4.90 4.65 5 4 PIN 1 IDENTIFIER 0.65 BSC 0.95 0.85 0.75 15° MAX 1.10 MAX 0.40 0.25 6° 0° 0.23 0.09 0.80 0.55 0.40 COMPLIANT TO JEDEC STANDARDS MO-187-AA 10-07-2009-B 0.15 0.05 COPLANARITY 0.10 Figure 42. 8-Lead Mini Small Outline Package [MSOP] (RM-8) Dimensions show in millimeters ORDERING GUIDE Model 1, 2 ADR3525WARMZ-R7 ADR3525WBRMZ-R7 ADR3530WARMZ-R7 ADR3530WBRMZ-R7 ADR3533WARMZ-R7 ADR3533WBRMZ-R7 ADR3540WARMZ-R7 ADR3540WBRMZ-R7 ADR3550WARMZ-R7 ADR3550WBRMZ-R7 1 2 Output Voltage (V) 2.500 2.500 3.000 3.000 3.300 3.300 4.096 4.096 5.000 5.000 Temperature Range −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C −40°C to +125°C Package Description 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP 8-Lead MSOP Package Option RM-8 RM-8 RM-8 RM-8 RM-8 RM-8 RM-8 RM-8 RM-8 RM-8 Ordering Quantity 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 Branding R3C R2T R3D R37 R3E R38 R3F R39 R3G R3B Z = RoHS Compliant Part. W = Qualified for Automotive Applications. AUTOMOTIVE PRODUCTS The ADR3525W/ADR3530W/ADR3533W/ADR3540W/ADR3550W models are available with controlled manufacturing to support the quality and reliability requirements of automotive applications. Note that these automotive models may have specifications that differ from the commercial models; therefore, designers should review the Specifications section of this data sheet carefully. Only the automotive grade products shown are available for use in automotive applications. Contact your local Analog Devices account representative for specific product ordering information and to obtain the specific Automotive Reliability reports for these models. ©2011 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D09594-0-9/11(0) Rev. 0 | Page 20 of 20