Micropower, Low Noise Precision Voltage References with Shutdown ADR390 PIN CONFIGURATION APPLICATIONS VIN 2 ADR390/ ADR391/ ADR392/ ADR395 5 GND V VOUT (SENSE) 3 (Not to Scale) 4 OUT (FORCE) Figure 1. 5-Lead TSOT (UJ Suffix) TE Table 1. B SO Battery-powered instrumentation Portable medical instrumentation Data acquisition systems Industrial process controls Automotive SHDN 1 Model ADR390B ADR390A ADR391B ADR391A ADR392B ADR392A ADR395B ADR395A Output Voltage (VO) 2.048 2.048 2.5 2.5 4.096 4.096 5.0 5.0 LE Compact 5-lead TSOT packages Low temperature coefficient B grade: 9 ppm/°C A grade: 25 ppm/°C Initial accuracy B grade: ±4 mV maximum (ADR390) A grade: ±6 mV maximum Ultralow output noise: 5 μV p-p (0.1 Hz to 10 Hz) Low dropout: 300 mV Low supply current 3 μA maximum in shutdown 120 μA maximum in operation No external capacitor required Output current: 5 mA Wide temperature range: −40°C to +125°C 00419-001 FEATURES Temperature Coefficient (ppm/°C) 9 25 9 25 9 25 9 25 Accuracy (mV) ±4 ±6 ±4 ±6 ±5 ±6 ±5 ±6 GENERAL DESCRIPTION The ADR39x family of micropower, low dropout voltage references provides a stable output voltage from a minimum supply of 300 mV above the output. Their advanced design eliminates the need for external capacitors, which further reduces board space and system cost. The combination of low power operation, small size, and ease of use makes the ADR39x precision voltage references ideally suited for batteryoperated applications. O The ADR390/ADR391/ADR392/ADR395 are precision 2.048 V, 2.5 V, 4.096 V, and 5 V band gap voltage references, respectively, featuring low power and high precision in a tiny footprint. Using patented temperature drift curvature correction techniques from Analog Devices, Inc., the ADR39x references achieve a low 9 ppm/°C of temperature drift in the TSOT package. Rev. H 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. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.461.3113 ©2002–2008 Analog Devices, Inc. All rights reserved. ADR390 TABLE OF CONTENTS ESD Caution...................................................................................7 Applications ....................................................................................... 1 Terminology .......................................................................................8 Pin Configuration ............................................................................. 1 Typical Performance Characteristics ..............................................9 General Description ......................................................................... 1 Theory of Operation ...................................................................... 16 Specifications..................................................................................... 3 Device Power Dissipation Considerations .............................. 16 ADR390 Electrical Characteristics............................................. 3 Shutdown Mode Operation ...................................................... 16 ADR391 Electrical Characteristics............................................. 4 Applications Information .............................................................. 17 ADR392 Electrical Characteristics............................................. 5 Basic Voltage Reference Connection ....................................... 17 ADR395 Electrical Characteristics............................................. 6 Capacitors .................................................................................... 18 Absolute Maximum Ratings............................................................ 7 Outline Dimensions ....................................................................... 19 Thermal Resistance ...................................................................... 7 Ordering Guide .......................................................................... 19 TE Features .............................................................................................. 1 REVISION HISTORY Changes to Thermal Resistance..................................................... 7 Moved ESD Caution........................................................................ 7 Changes to Figure 3, Figure 4, Figure 7, and Figure 8 ................ 9 Changes to Figure 11, Figure 12, Figure 13, and Figure 14...... 10 Changes to Figure 15, Figure 16, Figure 19, and Figure 20...... 11 Changes to Figure 23 and Figure 24............................................ 12 Changes to Figure 27..................................................................... 13 Changes to Ordering Guide ......................................................... 19 Updated Outline Dimensions ...................................................... 19 LE 2/08—Rev. F to Rev. G Changes to Ripple Rejection Ration Parameter (Table 2) ........... 3 Changes to Ripple Rejection Ration Parameter (Table 3) ........... 4 Changes to Ripple Rejection Ration Parameter (Table 4) ........... 5 Changes to Ripple Rejection Ration Parameter (Table 5) ........... 6 Changes to Figure 7 .......................................................................... 9 Changes to Outline Dimensions................................................... 19 Changes to Ordering Guide .......................................................... 19 B SO 5/05—Rev. E to Rev. F Changes to Table 5 ........................................................................... 7 Changes to Figure 2 ......................................................................... 9 4/04—Rev. D to Rev. E Changes to ADR390—Specifications ............................................ 3 Changes to ADR391—Specifications ............................................ 4 Changes to ADR392—Specifications ............................................ 5 Changes to ADR395—Specifications ............................................ 6 O 4/04—Rev. C to Rev. D Updated Format ................................................................ Universal Changes to Title ............................................................................... 1 Changes to Features......................................................................... 1 Changes to Applications ................................................................. 1 Changes to General Description ................................................... 1 Changes to Table 1 ........................................................................... 1 Changes to ADR390—Specifications ............................................ 3 Changes to ADR391—Specifications ............................................ 4 Changes to ADR392—Specifications ............................................ 5 Changes to ADR395—Specifications ............................................ 6 Changes to Absolute Maximum Ratings ...................................... 7 10/02—Rev. B to Rev. C Add parts ADR392 and ADR395 ....................................Universal Changes to Features ........................................................................ 1 Changes to General Description ................................................... 1 Additions to Table I ......................................................................... 1 Changes to Specifications ............................................................... 2 Changes to Ordering Guide ........................................................... 4 Changes to Absolute Maximum Ratings ...................................... 4 New TPCs 3, 4, 7, 8, 11, 12, 15, 16, 19, and 20 ............................ 6 New Figures 4 and 5 ...................................................................... 13 Deleted A Negative Precision Reference without Precision Resistors Section ............................................ 13 Edits to General-Purpose Current Source Section ................... 13 Updated Outline Dimensions ...................................................... 15 5/02—Rev. A to Rev. B Edits to Layout ...................................................................Universal Changes to Figure 6 ....................................................................... 13 Rev. H | Page 2 of 20 ADR390 SPECIFICATIONS ADR390 ELECTRICAL CHARACTERISTICS VIN = 2.5 V to 15 V, TA = 25°C, unless otherwise noted. Table 2. SUPPLY VOLTAGE HEADROOM LINE REGULATION LOAD REGULATION VIN − VO ∆VO/∆VIN ∆VO/∆ILOAD QUIESCENT CURRENT IIN VOLTAGE NOISE TURN-ON SETTLING TIME LONG-TERM STABILITY 1 OUTPUT VOLTAGE HYSTERESIS RIPPLE REJECTION RATIO SHORT CIRCUIT TO GND enp-p tR ∆VO ∆VO_HYS RRR ISC SHUTDOWN PIN Shutdown Supply Current Shutdown Logic Input Current Shutdown Logic Low Shutdown Logic High ISHDN ILOGIC VINL VINH Typ 2.048 2.048 Max 2.054 2.052 6 0.29 4 0.19 25 9 300 10 25 60 140 120 140 5 20 50 100 −80 25 30 1000 hours fIN = 60 Hz VIN = 5 V VIN = 15 V 3 500 0.8 2.4 The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period. O 1 Min 2.042 2.044 VIN = 2.5 V to 15 V, −40°C < TA < +125°C ILOAD = 0 mA to 5 mA, −40°C < TA < +85°C, VIN = 3 V ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 3 V No load −40°C < TA < +125°C 0.1 Hz to 10 Hz B SO INITIAL ACCURACY Conditions A grade B grade A grade A grade B grade B grade A grade: −40°C < TA < +125°C B grade: −40°C < TA < +125°C TE TEMPERATURE COEFFICIENT Symbol VO VO VOERR VOERR VOERR VOERR TCVO LE Parameter OUTPUT VOLTAGE Rev. H | Page 3 of 20 Unit V V mV % mV % ppm/°C ppm/°C mV ppm/V ppm/mA ppm/mA μA μA μV p-p μs ppm ppm dB mA mA μA nA V V ADR390 ADR391 ELECTRICAL CHARACTERISTICS VIN = 2.8 V to 15 V, TA = 25°C, unless otherwise noted. Table 3. INITIAL ACCURACY TEMPERATURE COEFFICIENT Symbol VO VO VOERR VOERR VOERR VOERR TCVO Conditions A grade B grade A grade A grade B grade B grade A grade, −40°C < TA < +125°C Min 2.494 2.496 Typ 2.5 2.5 B grade, −40°C < TA < +125°C QUIESCENT CURRENT IIN VOLTAGE NOISE TURN-ON SETTLING TIME LONG-TERM STABILITY 1 OUTPUT VOLTAGE HYSTERESIS RIPPLE REJECTION RATIO SHORT CIRCUIT TO GND enp-p tR ∆VO ∆VO_HYS RRR ISC SHUTDOWN PIN Shutdown Supply Current Shutdown Logic Input Current Shutdown Logic Low Shutdown Logic High ISHDN ILOGIC VINL VINH 300 VIN = 2.8 V to 15 V, −40°C < TA < +125°C ILOAD = 0 mA to 5 mA, −40°C < TA < +85°C, VIN = 3 V ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 3 V No load −40°C < TA < +125°C 0.1 Hz to 10 Hz 10 25 60 140 120 140 5 20 50 100 −80 25 30 1000 hours fIN = 60 Hz VIN = 5 V VIN = 15 V 3 500 0.8 2.4 The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period. O 1 9 LE VIN − VO ∆VO/∆VIN ∆VO/∆ILOAD B SO SUPPLY VOLTAGE HEADROOM LINE REGULATION LOAD REGULATION Max 2.506 2.504 6 0.24 4 0.16 25 TE Parameter OUTPUT VOLTAGE Rev. H | Page 4 of 20 Unit V V mV % mV % ppm/°C ppm/°C mV ppm/V ppm/mA ppm/mA μA μA μV p-p μs ppm ppm dB mA mA μA nA V V ADR390 ADR392 ELECTRICAL CHARACTERISTICS VIN = 4.3 V to 15 V, TA = 25°C, unless otherwise noted. Table 4. SUPPLY VOLTAGE HEADROOM LINE REGULATION LOAD REGULATION QUIESCENT CURRENT VIN − VO ∆VO/∆VIN ∆VO/∆ILOAD IIN VOLTAGE NOISE TURN-ON SETTLING TIME LONG-TERM STABILITY 1 OUTPUT VOLTAGE HYSTERESIS RIPPLE REJECTION RATIO SHORT CIRCUIT TO GND enp-p tR ∆VO ∆VO_HYS RRR ISC SHUTDOWN PIN Shutdown Supply Current Shutdown Logic Input Current Shutdown Logic Low Shutdown Logic High ISHDN ILOGIC VINL VINH Typ 4.096 4.096 Max 4.102 4.101 6 0.15 5 0.12 25 9 300 10 25 140 120 140 7 20 50 100 −80 25 30 1000 hours fIN = 60 Hz VIN = 5 V VIN = 15 V 3 500 0.8 2.4 The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period. O 1 Min 4.090 4.091 VIN = 4.3 V to 15 V, −40°C < TA < +125°C ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 5 V No load −40°C < TA < +125°C 0.1 Hz to 10 Hz B SO INITIAL ACCURACY Conditions A grade B grade A grade A grade B grade B grade A grade, −40°C < TA < +125°C B grade, −40°C < TA < +125°C TE TEMPERATURE COEFFICIENT Symbol VO VO VOERR VOERR VOERR VOERR TCVO LE Parameter OUTPUT VOLTAGE Rev. H | Page 5 of 20 Unit V V mV % mV % ppm/°C ppm/°C mV ppm/V ppm/mA μA μA μV p-p μs ppm ppm dB mA mA μA nA V V ADR390 ADR395 ELECTRICAL CHARACTERISTICS VIN = 5.3 V to 15 V, TA = 25°C, unless otherwise noted. Table 5. SUPPLY VOLTAGE HEADROOM LINE REGULATION LOAD REGULATION QUIESCENT CURRENT VIN − VO ∆VO/∆VIN ∆VO/∆ILOAD IIN VOLTAGE NOISE TURN-ON SETTLING TIME LONG-TERM STABILITY 1 OUTPUT VOLTAGE HYSTERESIS RIPPLE REJECTION RATIO SHORT CIRCUIT TO GND enp-p tR ∆VO ∆VO_HYS RRR ISC SHUTDOWN PIN Shutdown Supply Current Shutdown Logic Input Current Shutdown Logic Low Shutdown Logic High ISHDN ILOGIC VINL VINH Typ 5.000 5.000 Max 5.006 5.005 6 0.12 5 0.10 25 9 300 10 25 140 120 140 8 20 50 100 −80 25 30 1000 hours fIN = 60 Hz VIN = 5 V VIN = 15 V 3 500 0.8 2.4 The long-term stability specification is noncumulative. The drift of subsequent 1000 hour periods is significantly lower than in the first 1000 hour period. O 1 Min 4.994 4.995 VIN = 4.3 V to 15 V, −40°C < TA < +125°C ILOAD = 0 mA to 5 mA, −40°C < TA < +125°C, VIN = 6 V No load −40°C < TA < +125°C 0.1 Hz to 10 Hz B SO INITIAL ACCURACY Conditions A grade B grade A grade A grade B grade B grade A grade, −40°C < TA < +125°C B grade, −40°C < TA < +125°C TE TEMPERATURE COEFFICIENT Symbol VO VO VOERR VOERR VOERR VOERR TCVO LE Parameter OUTPUT VOLTAGE Rev. H | Page 6 of 20 Unit V V mV % mV % ppm/°C ppm/°C mV ppm/V ppm/mA μA μA μV p-p μs ppm ppm dB mA mA μA nA V V ADR390 ABSOLUTE MAXIMUM RATINGS At 25°C, unless otherwise noted. THERMAL RESISTANCE Table 6. θJA is specified for the worst-case conditions, that is, for a device soldered in a circuit board for surface-mount packages. Storage Temperature Range Operating Temperature Range Junction Temperature Range Lead Temperature (Soldering, 60 sec) Rating 18 V See derating curves −65°C to +125°C −40°C to +125°C −65°C to +125°C 300°C θJA 230 θJC 146 ESD CAUTION O B SO LE 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. Table 7. Package Type TSOT (UJ-5) TE Parameter Supply Voltage Output Short-Circuit Duration to GND Rev. H | Page 7 of 20 Unit °C/W ADR390 TERMINOLOGY Temperature Coefficient The change of output voltage with respect to operating temperature changes normalized by the output voltage at 25°C. This parameter is expressed in ppm/°C and can be determined by the following equation: VO (T2 ) – VO (T1 ) × 10 6 VO (25°C ) × (T2 – T1 ) ∆VO = VO(t0) − VO(t1) ⎞ ⎛ V (t 0 ) − VO (t 1 ) ΔVO [ppm] = ⎜⎜ O × 10 6 ⎟⎟ VO (t 0 ) ⎠ ⎝ (1) (2) where: VO (t0) is VO at 25°C at Time 0. VO (t1) is VO at 25°C after 1000 hours operation at 25°C. where: VO (25°C) is VO at 25°C. VO (T1) is VO at Temperature 1. VO (T2) is VO at Temperature 2. VO_HYS = VO(25°C) − VO_TC VO _ HYS [ppm] = VO (25 C ) − VO _ TC o LE Line Regulation The change in output voltage due to a specified change in input voltage. This parameter accounts for the effects of self-heating. Line regulation is expressed in either percent per volt, partsper-million per volt, or microvolts per volt change in input voltage. Thermal Hysteresis The change of output voltage after the device is cycled through temperatures from +25°C to –40°C to +125°C and back to +25°C. This is a typical value from a sample of parts put through such a cycle. TE TCVO [ppm/°C] = Long-Term Stability Typical shift of output voltage at 25°C on a sample of parts subjected to a test of 1000 hours at 25°C. VO (25 o C ) × 10 6 where: VO (25°C) is VO at 25°C VO_TC is VO at 25°C after a temperature cycle from +25°C to −40°C to +125°C and back to +25°C O B SO Load Regulation The change in output voltage due to a specified change in load current. This parameter accounts for the effects of self-heating. Load regulation is expressed in either microvolts per milliampere, parts-per-million per milliampere, or ohms of dc output resistance. Rev. H | Page 8 of 20 (3) (4) ADR390 TYPICAL PERFORMANCE CHARACTERISTICS 2.060 5.006 5.004 2.056 SAMPLE 3 5.002 VOUT (V) 2.052 SAMPLE 3 2.048 SAMPLE 1 4.998 SAMPLE 1 2.044 100 125 4.994 –40 30 65 TEMPERATURE (°C) 100 125 Figure 5. ADR395 Output Voltage vs. Temperature Figure 2. ADR390 Output Voltage vs. Temperature 140 SAMPLE 2 2.504 LE 2.506 +125°C 120 SAMPLE 3 2.496 2.494 –40 –5 30 65 TEMPERATURE (°C) 100 125 40 2.5 O SAMPLE 3 4.096 SAMPLE 2 4.094 SAMPLE 1 4.092 5.0 7.5 10.0 INPUT VOLTAGE (V) 12.5 15.0 Figure 6. ADR390 Supply Current vs. Input Voltage 140 120 SUPPLY CURRENT (µA) 4.098 –40°C 80 Figure 3. ADR391 Output Voltage vs. Temperature 4.100 +25°C 100 60 00419-004 2.498 B SO 2.500 +85°C 00419-007 SAMPLE 1 2.502 +125°C 100 +85°C +25°C 80 –40°C 4.088 –40 0 40 TEMPERATURE (°C) 80 125 40 2.5 00419-008 60 4.090 00419-005 VOUT (V) –5 5.0 7.5 10.0 INPUT VOLTAGE (V) 12.5 Figure 7. ADR391 Supply Current vs. Input Voltage Figure 4. ADR392 Output Voltage vs. Temperature Rev. H | Page 9 of 20 15.0 00419-006 30 65 TEMPERATURE (°C) TE –5 00419-003 4.996 2.040 –40 VOUT (V) SAMPLE 2 5.000 SUPPLY CURRENT (µA) VOUT (V) SAMPLE 2 ADR390 180 140 IL = 0mA TO 5mA 100 +25°C –40°C 80 00419-009 60 40 7 13 9 11 INPUT VOLTAGE (V) VIN = 5V VIN = 3V 140 120 100 80 –40 15 –10 20 50 TEMPERATURE (°C) 80 110 125 TE 5 160 Figure 8. ADR392 Supply Current vs. Input Voltage 00419-012 SUPPLY CURRENT (µA) 120 LOAD REGULATION (ppm/mA) +125°C Figure 11. ADR391 Load Regulation vs. Temperature 140 90 7.0 8.5 13.0 11.5 10.0 INPUT VOLTAGE (V) 60 Figure 9. ADR395 Supply Current vs. Input Voltage 120 60 VIN = 3V VIN = 5V 40 0 –40 –10 20 50 TEMPERATURE (°C) 80 110 125 IL = 0mA TO 5mA 00419-0 11 20 100 30 65 TEMPERATURE (°C) 80 LOAD REGULATION (ppm/mA) O LOAD REGULATION (ppm/mA) 80 –5 Figure 12. ADR392 Load Regulation vs. Temperature IL = 0mA TO 5mA 100 VIN = 5V 50 40 –40 14.5 VIN = 7.5V 00419-013 00419-010 40 5.5 70 70 VIN = 7.5V 60 50 40 30 –40 125 Figure 10. ADR390 Load Regulation vs. Temperature VIN = 5V –5 30 65 TEMPERATURE (°C) 100 Figure 13. ADR395 Load Regulation vs. Temperature Rev. H | Page 10 of 20 125 00419-014 –40°C 80 60 80 LE +25°C 100 B SO SUPPLY CURRENT (µA) 120 LOAD REGULATION (ppm/mA) IL = 0mA TO 5mA +125°C ADR390 14 25 12 LINE REGULATION (ppm/V) LINE REGULATION (ppm/V) 20 15 10 10 VIN = 5.3V TO 15V 8 6 4 5 20 50 TEMPERATURE (°C) 80 110 0 –40 125 20 LE VIN MIN (V) 0 –40 –10 20 50 TEMPERATURE (°C) 80 110 +25°C +85°C 0 1 2 3 LOAD CURRENT (mA) 3.6 +125°C 3.4 +85°C 3.2 +25°C 3.0 –40°C 4 30 65 TEMPERATURE (°C) 100 125 00419-017 –5 Figure 16. ADR392 Line Regulation vs. Temperature 2.6 0 1 2 3 LOAD CURRENT (mA) 4 5 Figure 19. ADR391 Minimum Input Voltage vs. Load Current Rev. H | Page 11 of 20 00419-020 2.8 2 0 –40 5 4 Figure 18. ADR390 Minimum Input Voltage vs. Load Current VIN MIN (V) O VIN = 4.4V TO 15V –40°C 2.4 2.0 125 Figure 15. ADR391 Line Regulation vs. Temperature 6 2.6 2.2 00419-016 5 LINE REGULATION (ppm/V) +125°C 00419-019 10 8 125 2.8 15 10 100 3.0 B SO LINE REGULATION (ppm/V) 25 12 30 65 TEMPERATURE (°C) Figure 17. ADR395 Line Regulation vs. Temperature Figure 14. ADR390 Line Regulation vs. Temperature 14 –5 00419-018 –10 TE 0 –40 00419-015 2 ADR390 70 4.8 –40°C +125°C +25°C 60 +125°C 4.6 TEMPERATURE: +25°C 50 VIN MIN (V) FREQUENCY +25°C 4.4 –40°C 4.2 40 30 20 4.0 4 5 Figure 20. ADR392 Minimum Input Voltage vs. Load Current +125 °C +25°C –40 °C 0 B SO 5.0 4.6 1 4 2 3 LOAD CURRENT (mA) 1k 900 800 700 TEMPERATURE: +25°C 50 5 +125°C +25°C VIN = 5V 400 ADR391 300 200 100 10 ADR390 100 1k FREQUENCY (Hz) 10k Figure 24. Voltage Noise Density vs. Frequency 0 0 VOLTAGE (2µV/DIV) 0 0 30 0 0 20 0 10 0.18 0.24 0 0.30 TIME (1s/DIV) Figure 25. ADR391 Typical Voltage Noise 0.1 Hz to 10 Hz Figure 22. ADR390 VOUT Hysteresis Distribution Rev. H | Page 12 of 20 00419-026 0 –0.24 –0.18 –0.12 –0.06 0 0.06 0.12 VOUT DEVIATION (mV) 0 00419-023 FREQUENCY O 40 –40°C 0.34 600 Figure 21. ADR395 Minimum Input Voltage vs. Load Current 60 0.19 500 00419-022 VIN MIN (V) 5.6 4.8 –0.26 –0.11 0.04 VOUT DEVIATION (mV) LE 5.8 5.2 –0.41 Figure 23. ADR391 VOUT Hysteresis Distribution 6.0 5.4 0 –0.56 00419-025 2 3 LOAD CURRENT (mA) TE 1 VOLTAGE NOISE DENSITY (nV/√Hz) 0 00419-021 3.8 00419-024 10 ADR390 CL = 0nF VLOAD ON LOAD OFF 00419-027 00419-030 VOLTAGE (1V/DIV) VOLTAGE (100µV/DIV) VOUT TIME (10µs/DIV) TE TIME (200µs/DIV) Figure 26. ADR391 Voltage Noise 10 Hz to 10 kHz Figure 29. ADR391 Load Transient Response CBYPASS = 0µF CL = 1nF VOUT VOUT VOLTAGE (1V/DIV) VOLTAGE LE 0.5V/DIV B SO 00419-028 1V/DIV LOAD OFF VLOAD ON 00419-031 LINE INTERRUPTION TIME (200µs/DIV) TIME (10µs/DIV) Figure 30. ADR391 Load Transient Response Figure 27. ADR391 Line Transient Response CL = 100nF CBYPASS = 0.1µF O 1V/DIV LOAD OFF VLOAD ON 00419-032 00419-029 VOUT VOLTAGE (1V/DIV) 0.5V/DIV LINE INTERRUPTION VOLTAGE VOUT TIME (200µs/DIV) TIME (10µs/DIV) Figure 31. ADR391 Load Transient Response Figure 28. ADR391 Line Transient Response Rev. H | Page 13 of 20 ADR390 VIN = 15V CBYPASS = 0.1µF 5V/DIV 2V/DIV VOLTAGE VOLTAGE VOUT VIN 2V/DIV VOUT 5V/DIV 00419-035 00419-033 VIN TIME (200µs/DIV) TE TIME (20µs/DIV) Figure 32. ADR391 Turn-On Response Time at 15 V Figure 34. ADR391 Turn-On/Turn-Off Response at 5 V with Capacitance VIN = 15V VIN RL = 500Ω 5V/DIV 2V/DIV VOLTAGE 2V/DIV 5V/DIV B SO 00419-034 VIN 00419-036 VOUT LE VOLTAGE VOUT TIME (40µs/DIV) TIME (200µs/DIV) Figure 35. ADR391 Turn-On/Turn-Off Response at 5 V with Resistor Load O Figure 33. ADR391 Turn-Off Response at 15 V Rev. H | Page 14 of 20 ADR390 100 RL = 500Ω CL = 100nF 90 80 5V/DIV VIN 70 60 CL = 0µF 50 40 30 00419-037 20 0 10 80 60 LE RIPPLE REJECTION (dB) 40 20 0 –20 –40 –60 00419-038 B SO –80 100 1k 10k FREQUENCY (Hz) 100k 1k 10k FREQUENCY (Hz) CL = 0.1µF 100k Figure 38. Output Impedance vs. Frequency Figure 36. ADR391 Turn-On/Turn-Off Response at 5 V –120 10 100 TE TIME (200µs/DIV) –100 CL = 1µF 10 1M O Figure 37. Ripple Rejection vs. Frequency Rev. H | Page 15 of 20 1M 00419-039 VOLTAGE VOUT OUTPUT IMPEDANCE (Ω) 2V/DIV ADR390 THEORY OF OPERATION Band gap references are the high performance solution for low supply voltage and low power voltage reference applications, and the ADR390/ADR391/ADR392/ADR395 are no exception. The uniqueness of these devices lies in the architecture. As shown in Figure 39, the ideal zero TC band gap voltage is referenced to the output, not to ground. Therefore, if noise exists on the ground line, it is greatly attenuated on VOUT. The band gap cell consists of the PNP pair, Q51 and Q52, running at unequal current densities. The difference in VBE results in a voltage with a positive TC, which is amplified by a ratio of The ADR390/ADR391/ADR392/ADR395 are capable of delivering load currents to 5 mA, with an input voltage that ranges from 2.8 V (ADR391 only) to 15 V. When these devices are used in applications with large input voltages, care should be taken to avoid exceeding the specified maximum power dissipation or junction temperature because it could result in premature device failure. The following formula should be used to calculate the maximum junction temperature or dissipation of the device: R58 R54 PD = This PTAT voltage, combined with VBEs of Q51 and Q52, produces a stable band gap voltage. VIN Q1 VOUT (FORCE) VOUT (SENSE) R59 R44 SHUTDOWN MODE OPERATION The ADR390/ADR391/ADR392/ADR395 include a shutdown feature that is TTL/CMOS level compatible. A logic low or a zero volt condition on the SHDN pin is required to turn the devices off. During shutdown, the output of the reference becomes a high impedance state, where its potential would then be determined by external circuitry. If the shutdown feature is not used, the SHDN pin should be connected to VIN (Pin 2). R49 R54 Q51 R53 Q52 R48 R60 R61 GND 00419-040 SHDN (5) where: TJ and TA are, respectively, the junction and ambient temperatures. PD is the device power dissipation. θJA is the device package thermal resistance. B SO R58 θ JA LE Reduction in the band gap curvature is performed by the ratio of Resistors R44 and R59, one of which is linearly temperature dependent. Precision laser trimming and other patented circuit techniques are used to further enhance the drift performance. TJ – T A TE 2× DEVICE POWER DISSIPATION CONSIDERATIONS O Figure 39. Simplified Schematic Rev. H | Page 16 of 20 ADR390 APPLICATIONS INFORMATION BASIC VOLTAGE REFERENCE CONNECTION The circuit shown in Figure 40 illustrates the basic configuration for the ADR39x family. Decoupling capacitors are not required for circuit stability. The ADR39x family is capable of driving capacitive loads from 0 μF to 10 μF. However, a 0.1 μF ceramic output capacitor is recommended to absorb and deliver the charge, as required by a dynamic load. GND SHDN ADR39x * VIN VOUT (FORCE) VOUT (SENSE) 0.1µF CB *NOT REQUIRED * TE CB OUTPUT 00419-041 INPUT 0.1µF A Negative Precision Reference without Precision Resistors Some applications may require two reference voltage sources, which are a combined sum of standard outputs. Figure 41 shows how this stacked output reference can be implemented. OUTPUT TABLE U1/U2 VIN 2.048 2.5 4.096 5 4.096 5.0 8.192 10 B SO ADR390/ADR390 ADR391/ADR391 ADR392/ADR392 ADR395/ADR395 VOUT1 (V) VOUT2 (V) A negative reference can be easily generated by adding an A1 op amp and is configured as shown in Figure 42. VOUT (FORCE) and VOUT (SENSE) are at virtual ground and, therefore, the negative reference can be taken directly from the output of the op amp. The op amp must be dual-supply, low offset, and rail-to-rail if the negative supply voltage is close to the reference output. LE Figure 40. Basic Configuration for the ADR39x Family Stacking Reference ICs for Arbitrary Outputs While this concept is simple, a precaution is required. Because the lower reference circuit must sink a small bias current from U2 plus the base current from the series PNP output transistor in U2, either the external load of U1 or an external resistor must provide a path for this current. If the U1 minimum load is not well defined, the external resistor should be used and set to a value that conservatively passes 600 μA of current with the applicable VOUT1 across it. Note that the two U1 and U2 reference circuits are treated locally as macrocells; each has its own bypasses at input and output for best stability. Both U1 and U2 in this circuit can source dc currents up to their full rating. The minimum input voltage, VIN, is determined by the sum of the outputs, VOUT2, plus the dropout voltage of U2. VIN VOUT (FORCE) SHDN VOUT (SENSE) U2 C2 0.1µF VIN SHDN VOUT (FORCE) +VDD GND VOUT2 –VREF A1 VOUT (SENSE) O GND U1 SHDN VOUT (FORCE) Figure 42. Negative Reference General-Purpose Current Source VIN C2 0.1µF –VDD 00419-043 SHUTDOWN Table in Figure 41). For example, if both U1 and U2 are ADR391s, VOUT1 is 2.5 V and VOUT2 is 5.0 V. VOUT1 VOUT (SENSE) 00419-042 GND Figure 41. Stacking Voltage References with the ADR390/ADR391/ADR392/ADR395 Two reference ICs are used, fed from an unregulated input, VIN. The outputs of the individual ICs are connected in series, which provide two output voltages, VOUT1 and VOUT2. VOUT1 is the terminal voltage of U1, while VOUT2 is the sum of this voltage and the terminal voltage of U2. U1 and U2 are chosen for the two voltages that supply the required outputs (see the Output Many times in low power applications, the need arises for a precision current source that can operate on low supply voltages. The ADR390/ADR391/ADR392/ADR395 can be configured as a precision current source. As shown in Figure 43, the circuit configuration is a floating current source with a grounded load. The reference output voltage is bootstrapped across RSET, which sets the output current into the load. With this configuration, circuit precision is maintained for load currents in the range from the reference supply current, typically 90 μA to approximately 5 mA. Rev. H | Page 17 of 20 ADR390 VIN R1 4.7kΩ VIN U1 SHDN SHDN GND VIN ADR39x Q1 Q2N2222 VOUT (FORCE) VIN VOUT (SENSE) ISET VOUT (FORCE) 0.1µF GND R1 RL RSET ISY ADJUST ISY (ISET) ADR39x R1 Q2 Q2N4921 RS 00419-D-046 VOUT (SENSE) P1 Figure 45. ADR39x for High Output Current with Darlington Drive Configuration IOUT = ISET + ISY (ISET ) TE CAPACITORS 00419-044 RL Input Capacitor Figure 43. A General-Purpose Current Source High Power Performance with Current Limit Output Capacitor LE In some cases, the user may want higher output current delivered to a load and still achieve better than 0.5% accuracy out of the ADR39x. The accuracy for a reference is normally specified on the data sheet with no load. However, the output voltage changes with load current. Input capacitors are not required on the ADR39x. There is no limit for the value of the capacitor used on the input, but a 1 μF to 10 μF capacitor on the input improves transient response in applications where the supply suddenly changes. An additional 0.1 μF in parallel also helps reduce noise from the supply. B SO The circuit shown in Figure 44 provides high current without compromising the accuracy of the ADR39x. The series pass transistor, Q1, provides up to 1 A load current. The ADR39x delivers only the base drive to Q1 through the force pin. The sense pin of the ADR39x is a regulated output and is connected to the load. The Transistor Q2 protects Q1 during short-circuit limit faults by robbing its base drive. The maximum current is ILMAX ≈ 0.6 V/RS (6) U1 SHDN GND VIN Q1 Q2N4921 O VOUT (FORCE) ADR39x 50 Q2 Q2N2222 RL 0 –50 –100 RS IL –150 00419-045 VOUT (SENSE) 100 Figure 44. ADR39x for High Power Performance with Current Limit 00419-002 R1 4.7kΩ 150 DRIFT (ppm) VIN The ADR39x does not require output capacitors for stability under any load condition. An output capacitor, typically 0.1 μF, filters out any low level noise voltage and does not affect the operation of the part. On the other hand, the load transient response can improve with the addition of a 1 μF to 10 μF output capacitor in parallel. A capacitor here acts as a source of stored energy for a sudden increase in load current. The only parameter that degrades by adding an output capacitor is the turn-on time, and it depends on the size of the capacitor chosen. 0 100 200 300 400 500 600 TIME (Hours) 700 800 900 1000 Figure 46. ADR391 Typical Long-Term Drift over 1000 Hours A similar circuit function can also be achieved with the Darlington transistor configuration, as shown in Figure 45. Rev. H | Page 18 of 20 ADR390 OUTLINE DIMENSIONS 2.90 BSC 5 4 2.80 BSC 1.60 BSC 1 2 3 PIN 1 0.95 BSC 1.90 BSC *0.90 0.87 0.84 0.10 MAX 0.50 0.30 0.20 0.08 8° 4° 0° TE *1.00 MAX SEATING PLANE 0.60 0.45 0.30 *COMPLIANT TO JEDEC STANDARDS MO-193-AB WITH THE EXCEPTION OF PACKAGE HEIGHT AND THICKNESS. ORDERING GUIDE Initial Accuracy (mV) (%) ±6 0.29 ±6 0.29 ±4 0.19 ±4 0.19 ±6 0.24 ±6 0.24 ±4 0.16 ±4 0.16 ±6 0.15 ±6 0.15 ±5 0.12 ±5 0.12 ±6 0.12 ±6 0.12 ±5 0.10 ±5 0.10 Temperature Coefficient (ppm/°C) 25 25 9 9 25 25 9 9 25 25 9 9 25 25 9 9 Package Description 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT 5-Lead TSOT O B SO Models ADR390AUJZ-REEL7 1 ADR390AUJZ-R21 ADR390BUJZ-REEL71 ADR390BUJZ-R21 ADR391AUJZ-REEL71 ADR391AUJZ-R21 ADR391BUJZ-REEL71 ADR391BUJZ-R21 ADR392AUJZ-REEL71 ADR392AUJZ-R21 ADR392BUJZ-REEL71 ADR392BUJZ-R21 ADR395AUJZ-REEL71 ADR395AUJZ-R21 ADR395BUJZ-REEL71 ADR395BUJZ-R21 Output Voltage (VO) 2.048 2.048 2.048 2.048 2.5 2.5 2.5 2.5 4.096 4.096 4.096 4.096 5.0 5.0 5.0 5.0 LE Figure 47. 5-Lead Thin Small Outline Transistor Package [TSOT] (UJ-5) Dimensions shown in millimeters 1 Z = RoHS Compliant Part. Rev. H | Page 19 of 20 Package Option UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 UJ-5 Branding R0A R0A R0B R0B R1A R1A R1B R1B RCA RCA RCB RCB RDA RDA RDB RDB Number of Parts per Reel 3,000 250 3,000 250 3,000 250 3,000 250 3,000 250 3,000 250 3,000 250 3,000 250 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 −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 ADR390 O B SO LE TE NOTES ©2002–2008 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. D00419-0-2/08(G) Rev. H | Page 20 of 20