LT1460 Micropower Precision Series Reference Family Features n n n n n n n n n n Description Trimmed to High Accuracy: 0.075% Max Low Drift: 10ppm/°C Max Industrial Temperature Range Temperature Coefficient Guaranteed to 125°C Low Supply Current: 130µA Max (LT1460-2.5) Minimum Output Current: 20mA No Output Capacitor Required Reverse Battery Protection Minimum Input/Output Differential: 0.9V Available in S0-8, MSOP-8, PDIP-8, TO-92 and SOT- 23 Package Applications n n n n n Handheld Instruments Precision Regulators A/D and D/A Converters Power Supplies Hard Disk Drives The LT®1460 is a micropower bandgap reference that combines very high accuracy and low drift with low power dissipation and small package size. This series reference uses curvature compensation to obtain low temperature coefficient and trimmed precision thin-film resistors to achieve high output accuracy. The reference will supply up to 20mA with excellent line regulation characteristics, making it ideal for precision regulator applications. This series reference provides supply current and power dissipation advantages over shunt references that must idle the entire load current to operate. Additionally, the LT1460 does not require an output compensation capacitor, yet is stable with capacitive loads. This feature is important where PC board space is a premium or fast settling is demanded. In the event of a reverse battery connection, these references will not conduct current, and are therefore protected from damage. The LT1460 is available in the 8-lead MSOP, SO, PDIP and the 3-lead TO-92 and SOT23 packages. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application Typical Distribution of Output Voltage S8 Package Basic Connection 20 LT1460-2.5 IN C1 0.1µF OUT 18 2.5V 16 GND 1400 PARTS FROM 2 RUNS 14 1460 TA01 UNITS (%) 3.4V TO 20V 12 10 8 6 4 2 0 –0.10 –0.06 0.06 –0.02 0 0.02 OUTPUT VOLTAGE ERROR (%) 0.10 1460 TA02 1460fc LT1460 Absolute Maximum Ratings (Note 1) Input Voltage..............................................................30V Reverse Voltage....................................................... –15V Output Short-Circuit Duration, TA = 25°C VIN > 10V.............................................................5 sec VIN ≤ 10V...................................................... Indefinite Specified Temperature Range (Note 10) Commercial (C)......................................... 0°C to 70°C Industrial (I)..........................................–40°C to 85°C High (H).............................................. –40°C to 125°C Storage Temperature Range (Note 2)...... –65°C to 150°C Lead Temperature (Soldering, 10 sec)................... 300°C Pin Configuration TOP VIEW IN 1 3 GND OUT 2 S3 PACKAGE 3-LEAD PLASTIC SOT-23 TJMAX = 125°C, θJA = 228°C/W TOP VIEW TOP VIEW DNC* 1 8 DNC* DNC* 1 8 DNC* VIN 2 7 DNC* VIN 2 7 DNC* DNC* 3 6 VOUT DNC* 3 6 VOUT GND 4 5 DNC* GND 4 5 DNC* N8 PACKAGE 8-LEAD PLASTIC DIP S8 PACKAGE 8-LEAD PLASTIC SO *CONNECTED INTERNALLY. DO NOT CONNECT EXTERNAL CIRCUITRY TO THESE PINS TJMAX = 150°C, θJA = 130°C/W *CONNECTED INTERNALLY. DO NOT CONNECT EXTERNAL CIRCUITRY TO THESE PINS TJMAX = 150°C, θJA = 190°C/W TOP VIEW DNC* VIN DNC* GND 1 2 3 4 BOTTOM VIEW 8 7 6 5 DNC* DNC* VOUT DNC* 1 2 3 VIN VOUT GND MS8 PACKAGE 8-LEAD PLASTIC MSOP *CONNECTED INTERNALLY. DO NOT CONNECT EXTERNAL CIRCUITRY TO THESE PINS TJMAX = 150°C, θJA = 250°C/W Z PACKAGE 3-LEAD TO-92 PLASTIC TJMAX = 150°C, θJA = 160°C/W 1460fc LT1460 Order Information Lead Free Finish TAPE AND REEL (MINI) TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LT1460HCS3-2.5#TRMPBF LT1460HCS3-2.5#TRMPBF LTAC or LTH8† 3-Lead Plastic SOT-23 0°C to 70°C LT1460JCS3-2.5#TRMPBF LT1460JCS3-2.5#TRPBF LTAD or LTH8† 3-Lead Plastic SOT-23 0°C to 70°C LT1460KCS3-2.5#TRMPBF LT1460KCS3-2.5#TRPBF LTAE or LTH8† 3-Lead Plastic SOT-23 0°C to 70°C LT1460HCS3-3#TRMPBF LT1460HCS3-3#TRPBF LTAN or LTH9† 3-Lead Plastic SOT-23 0°C to 70°C LT1460JCS3-3#TRMPBF LT1460JCS3-3#TRPBF LTAP or LTH9† 3-Lead Plastic SOT-23 0°C to 70°C LT1460KCS3-3#TRMPBF LT1460KCS3-3#TRPBF LTAQ or LTH9† 3-Lead Plastic SOT-23 0°C to 70°C LT1460HCS3-3.3#TRMPBF LT1460HCS3-3.3#TRPBF LTAR or LTJ1† 3-Lead Plastic SOT-23 0°C to 70°C LT1460JCS3-3.3#TRMPBF LT1460JCS3-3.3#TRPBF LTAS or LTJ1† 3-Lead Plastic SOT-23 0°C to 70°C LT1460KCS3-3.3#TRMPBF LT1460KCS3-3.3#TRPBF LTAT or LTJ1† 3-Lead Plastic SOT-23 0°C to 70°C LT1460HCS3-5#TRMPBF LT1460HCS3-5#TRPBF LTAK or LTJ2† 3-Lead Plastic SOT-23 0°C to 70°C LT1460JCS3-5#TRMPBF LT1460JCS3-5#TRPBF LTAL or LTJ2† 3-Lead Plastic SOT-23 0°C to 70°C LT1460KCS3-5#TRMPBF LT1460KCS3-5#TRPBF LTAM or LTJ2† 3-Lead Plastic SOT-23 0°C to 70°C LT1460HCS3-10#TRMPBF LT1460HCS3-10#TRPBF LTAU or LTJ3† 3-Lead Plastic SOT-23 0°C to 70°C LT1460JCS3-10#TRMPBF LT1460JCS3-10#TRPBF LTAV or LTJ3† 3-Lead Plastic SOT-23 0°C to 70°C LTAW or LTJ3† 3-Lead Plastic SOT-23 LT1460KCS3-10#TRMPBF LT1460KCS3-10#TRPBF TRM = 500 pieces. *Temperature grades and parametric grades are identified by a label on the shipping container. †Product grades are identified with either part marking. Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ 0°C to 70°C LEAD FREE FINISH TAPE AND REEL PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LT1460ACN8-2.5#PBF LT1460ACN8-2.5#TRPBF 8-Lead Plastic DIP 0°C to 70°C LT1460BIN8-2.5#PBF LT1460BIN8-2.5#TRPBF 8-Lead Plastic DIP –40°C to 85°C LT1460DCN8-2.5#PBF LT1460DCN8-2.5#TRPBF 8-Lead Plastic DIP 0°C to 70°C LT1460EIN8-2.5#PBF LT1460EIN8-2.5#TRPBF 8-Lead Plastic DIP –40°C to 85°C LT1460ACN8-5#PBF LT1460ACN8-5#TRPBF 8-Lead Plastic DIP 0°C to 70°C LT1460BIN8-5#PBF LT1460BIN8-5#TRPBF 8-Lead Plastic DIP –40°C to 85°C LT1460DCN8-5#PBF LT1460DCN8-5#TRPBF 8-Lead Plastic DIP 0°C to 70°C LT1460EIN8-5#PBF LT1460EIN8-5#TRPBF 8-Lead Plastic DIP –40°C to 85°C LT1460ACN8-10#PBF LT1460ACN8-10#TRPBF 8-Lead Plastic DIP 0°C to 70°C LT1460BIN8-10#PBF LT1460BIN8-10#TRPBF 8-Lead Plastic DIP –40°C to 85°C LT1460DCN8-10#PBF LT1460DCN8-10#TRPBF 8-Lead Plastic DIP 0°C to 70°C LT1460EIN8-10#PBF LT1460EIN8-10#TRPBF 8-Lead Plastic DIP –40°C to 85°C LT1460ACS8-2.5#PBF LT1460ACS8-2.5#TRPBF 1460A2 8-Lead Plastic SO 0°C to 70°C LT1460BIS8-2.5#PBF LT1460BIS8-2.5#TRPBF 460BI2 8-Lead Plastic SO –40°C to 85°C LT1460DCS8-2.5#PBF LT1460DCS8-2.5#TRPBF 1460D2 8-Lead Plastic SO 0°C to 70°C LT1460EIS8-2.5#PBF LT1460EIS8-2.5#TRPBF 460EI2 8-Lead Plastic SO –40°C to 85°C LT1460LHS8-2.5#PBF LT1460LHS8-2.5#TRPBF 60LH25 8-Lead Plastic SO 0°C to 70°C LT1460MHS8-2.5#PBF LT1460MHS8-2.5#TRPBF 60MH25 8-Lead Plastic SO –40°C to 85°C LT1460ACS8-5#PBF LT1460ACS8-5#TRPBF 1460A5 8-Lead Plastic SO 0°C to 70°C LT1460BIS8-5#PBF LT1460BIS8-5#TRPBF 460BI5 8-Lead Plastic SO –40°C to 85°C PART MARKING 1460fc LT1460 order information LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION SPECIFIED TEMPERATURE RANGE LT1460DCS8-5#PBF LT1460DCS8-5#TRPBF 1460D5 8-Lead Plastic SO 0°C to 70°C LT1460EIS8-5#PBF LT1460EIS8-5#TRPBF 460EI5 8-Lead Plastic SO –40°C to 85°C LT1460LHS8-5#PBF LT1460LHS8-5#TRPBF 460LH5 8-Lead Plastic SO 0°C to 70°C LT1460MHS8-5#PBF LT1460MHS8-5#TRPBF 460MH5 8-Lead Plastic SO –40°C to 85°C LT1460ACS8-10#PBF LT1460ACS8-10#TRPBF 1460A1 8-Lead Plastic SO 0°C to 70°C LT1460BIS8-10#PBF LT1460BIS8-10#TRPBF 460BI1 8-Lead Plastic SO –40°C to 85°C LT1460DCS8-10#PBF LT1460DCS8-10#TRPBF 1460D1 8-Lead Plastic SO 0°C to 70°C LT1460EIS8-10#PBF LT1460EIS8-10#TRPBF 460EI1 8-Lead Plastic SO –40°C to 85°C LT1460CCMS8-2.5#PBF LT1460CCMS8-2.5#TRPBF LTAA 8-Lead Plastic MSOP 0°C to 70°C LT1460FCMS8-2.5#PBF LT1460FCMS8-2.5#TRPBF LTAB 8-Lead Plastic MSOP 0°C to 70°C LT1460CCMS8-5#PBF LT1460CCMS8-5#TRPBF LTAF 8-Lead Plastic MSOP 0°C to 70°C LT1460FCMS8-5#PBF LT1460FCMS8-5#TRPBF LTAG 8-Lead Plastic MSOP 0°C to 70°C LT1460CCMS8-10#PBF LT1460CCMS8-10#TRPBF LTAH 8-Lead Plastic MSOP 0°C to 70°C LT1460FCMS8-10#PBF LT1460FCMS8-10#TRPBF LTAJ 8-Lead Plastic MSOP 0°C to 70°C LT1460GCZ-2.5#PBF LT1460GCZ-2.5#TRPBF 3-Lead Plastic TO-92 0°C to 70°C LT1460GIZ-2.5#PBF LT1460GIZ-2.5#TRPBF 3-Lead Plastic TO-92 –40°C to 85°C LT1460GCZ-5#PBF LT1460GCZ-5#TRPBF 3-Lead Plastic TO-92 0°C to 70°C LT1460GIZ-5#PBF LT1460GIZ-5#TRPBF 3-Lead Plastic TO-92 –40°C to 85°C LT1460GCZ-10#PBF LT1460GCZ-10#TRPBF 3-Lead Plastic TO-92 0°C to 70°C LT1460GIZ-10#PBF LT1460GIZ-10#TRPBF 3-Lead Plastic TO-92 –40°C to 85°C Consult LTC Marketing for parts specified with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ Available Options ACCURACY (%) TEMPERATURE COEFFICIENT (ppm/°C) N8 S8 0°C to 70°C 0.075 10 LT1460ACN8 LT1460ACS8 –40°C to 85°C 0.10 10 LT1460BIN8 LT1460BIS8 0°C to 70°C 0.10 15 0°C to 70°C 0.10 20 LT1460DCN8 LT1460DCS8 –40°C to 85°C 0.125 20 LT1460EIN8 LT1460EIS8 0°C to 70°C 0.15 25 0°C to 70°C 0.25 25 LT1460GCZ –40°C to 85°C 0.25 25 LT1460GIZ –40°C to 85°C/125°C 0.20 20/50 LT1460LHS8 –40°C to 125°C 0.20 50 LT1460MHS8 0°C to 70°C 0.20 20 0°C to 70°C 0.40 20 LT1460JCS3 0°C to 70°C 0.50 50 LT1460KCS3 TEMPERATURE PACKAGE TYPE MS8 Z S3 LT1460CCMS8 LT1460FCMS8 LT1460HCS3 1460fc LT1460 Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = VOUT + 2.5V, IOUT = 0 unless otherwise specified. PARAMETER CONDITIONS Output Voltage LT1460ACN8-2.5, ACS8-2.5 2.49813 –0.075 MIN 2.50188 0.075 V % LT1460BIN8-2.5, BIS8-2.5, CCMS8-2.5, DCN8-2.5, DCS8-2.5 2.4975 –0.10 2.5025 0.10 V % LT1460EIN8-2.5, EIS8-2.5 2.49688 –0.125 2.50313 0.125 V % LT1460FCMS8-2.5 2.49625 –0.15 2.50375 0.15 V % LT1460GCZ-2.5, GIZ-2.5 2.49375 –0.25 2.50625 0.25 V % 2.495 –0.20 2.505 0.20 V % 4.99625 –0.075 5.00375 0.075 V % 4.995 –0.10 5.005 0.10 V % LT1460EIN8-5, EIS8-5 4.99375 –0.125 5.00625 0.125 V % LT1460FCMS8-5 4.9925 –0.15 5.0075 0.15 V % LT1460GCZ-5, GIZ-5 4.9875 –0.25 5.0125 0.25 V % LT1460LHS8-5, MHS8-5 4.990 –0.20 5.010 0.20 V % LT1460ACN8-10, ACS8-10 9.9925 –0.075 10.0075 0.075 V % LT1460BIN8-10, BIS8-10, CCMS8-10, DCN8-10, DCS8-10 9.990 –0.10 10.010 0.10 V % LT1460EIN8-10, EIS8-10 9.9875 –0.125 10.0125 0.125 V % LT1460FCMS8-10 9.985 –0.15 10.0015 0.15 V % LT1460GCZ-10, GIZ-10 9.975 –0.25 10.025 0.25 V % LT1460HC LT1460JC LT1460KC –0.2 –0.4 –0.5 0.2 0.4 0.5 % % % LT1460LHS8-2.5, MHS8-2.5 LT1460ACN8-5, ACS8-5 LT1460BIN8-5, BIS8-5, CCMS8-5, DCN8-5, DCS8-5 Output Voltage Temperature Coefficient (Note 3) TYP MAX UNITS TMIN ≤ TJ ≤ TMAX LT1460ACN8, ACS8, BIN8, BIS8 LT1460CCMS8 LT1460DCN8, DCS8, EIN8, EIS8 LT1460FCMS8, GCZ, GIZ LT1460LHS8 –40°C to 85°C –40°C to 125°C LT1460MHS8 –40°C to 125°C l l l l l l l 5 7 10 12 10 25 25 10 15 20 25 20 50 50 ppm/°C ppm/°C ppm/°C ppm/°C ppm/°C ppm/°C ppm/°C LT1460HC LT1460JC LT1460KC l l l 10 10 25 20 20 50 ppm/°C ppm/°C ppm/°C 1460fc LT1460 Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = VOUT + 2.5V, IOUT = 0 unless otherwise specified. PARAMETER CONDITIONS Line Regulation LT1460A, LT1460B, LT1460C, LT1460D, LT1460E, LT1460F, LT1460G, LT1460H, LT1460L, LT1460M VOUT + 0.9V ≤ VIN ≤ VOUT + 2.5V MIN TYP MAX UNITS 30 60 80 ppm/V ppm/V 10 25 35 ppm/V ppm/V 150 800 1000 ppm/V ppm/V 50 100 130 ppm/V ppm/V 1500 2800 3500 ppm/mA ppm/mA 80 135 180 ppm/mA ppm/mA 70 100 140 ppm/mA ppm/mA 1000 3000 4000 ppm/mA ppm/mA 50 200 300 ppm/mA ppm/mA 20 70 100 ppm/mA ppm/mA ΔP = 200mW 0.5 2.5 ppm/mW ΔP = 200mW 2.5 10 ppm/mW l 0.9 V l 1.3 1.4 V V l VOUT + 2.5V ≤ VIN ≤ 20V l LT1460HC, LT1460JC, LT1460KC VOUT + 0.9V ≤ VIN ≤ VOUT + 2.5V l VOUT + 2.5V ≤ VIN ≤ 20V l Load Regulation Sourcing (Note 4) LT1460A, LT1460B, LT1460C, LT1460D, LT1460E, LT1460F, LT1460G, LT1460H, LT1460L, LT1460M IOUT = 100µA l IOUT = 10mA l IOUT = 20mA 0°C to 70°C LT1460HC, LT1460JC, LT1460KC l IOUT = 100µA l IOUT = 10mA l IOUT = 20mA l Thermal Regulation (Note 5) LT1460A, LT1460B, LT1460C, LT1460D, LT1460E, LT1460F, LT1460G, LT1460H, LT1460L, LT1460M LT1460HC, LT1460JC, LT1460KC Dropout Voltage (Note 6) VIN – VOUT, IOUT = 0 VIN – VOUT, IOUT = 10mA Output Current Short VOUT to GND Reverse Leakage VIN = –15V Supply Current LT1460-2.5 40 l 10 µA 100 130 165 µA µA 125 175 225 µA µA 190 270 360 µA µA 115 145 175 µA µA 145 180 220 µA µA 145 180 220 µA µA 160 200 240 µA µA 215 270 350 µA µA l LT1460-5 l LT1460-10 l LT1460S3-2.5 l LT1460S3-3 l LT1460S3-3.3 l LT1460S3-5 l LT1460S3-10 l mA 0.5 1460fc LT1460 Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = VOUT + 2.5V, IOUT = 0 unless otherwise specified. PARAMETER CONDITIONS Output Voltage Noise (Note 7) LT1460A, LT1460B, LT1460C, LT1460D, LT1460E, LT1460F, LT1460G, LT1460H, LT1460L, LT1460M LT1460-2.5 0.1Hz ≤ f ≤ 10Hz 10Hz ≤ f ≤ 1kHz 10 10 µVP-P µVRMS LT1460-5 0.1Hz ≤ f ≤ 10Hz 10Hz ≤ f ≤ 1kHz 20 20 µVP-P µVRMS LT1460-10 0.1Hz ≤ f ≤ 10Hz 10Hz ≤ f ≤ 1kHz 40 35 µVP-P µVRMS 4 4 ppm (P-P) ppm (RMS) 40 ppm/√kHr 100 ppm/√kHr 25 160 ppm ppm 50 250 ppm ppm LT1460HC, LT1460JC, LT1460KC MIN 0.1Hz ≤ f ≤ 10Hz 10Hz ≤ f ≤ 1kHz Long-Term Stability of Output Voltage (Note 8) S8 Pkg LT1460HC, LT1460JC, LT1460KC Hysteresis (Note 9) LT1460A, LT1460B, LT1460C, LT1460D, LT1460E, LT1460F, LT1460G, LT1460H, LT1460L, LT1460M LT1460HC, LT1460JC, LT1460KC ΔT = 0°C to 70°C ΔT = –40°C to 85°C ΔT = 0°C to 70°C ΔT = –40°C to 85°C Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: If the part is stored outside of the specified temperature range, the output may shift due to hysteresis. Note 3: Temperature coefficient is measured by dividing the change in output voltage by the specified temperature range. Incremental slope is also measured at 25°C. Note 4: Load regulation is measured on a pulse basis from no load to the specified load current. Output changes due to die temperature change must be taken into account separately. Note 5: Thermal regulation is caused by die temperature gradients created by load current or input voltage changes. This effect must be added to normal line or load regulation. This parameter is not 100% tested. Note 6: Excludes load regulation errors. For LT1460S3, ΔVOUT ≤ 0.2%. For all other packages, ΔVOUT ≤ 0.1%. Note 7: Peak-to-peak noise is measured with a single highpass filter at 0.1Hz and 2-pole lowpass filter at 10Hz. The unit is enclosed in a still-air environment to eliminate thermocouple effects on the leads. The test time is 10 sec. RMS noise is measured with a single highpass filter at 10Hz and a 2-pole lowpass filter at 1kHz. The resulting output is full wave rectified l l TYP MAX UNITS and then integrated for a fixed period, making the final reading an average as opposed to RMS. A correction factor of 1.1 is used to convert from average to RMS and a second correction of 0.88 is used to correct for the nonideal pass band of the filters. Note 8: Long-term stability typically has a logarithmic characteristic and therefore, changes after 1000 hours tend to be much smaller than before that time. Total drift in the second thousand hours is normally less than one third that of the first thousand hours with a continuing trend toward reduced drift with time. Significant improvement in long-term drift can be realized by preconditioning the IC with a 100 hour to 200 hour, 125°C burn-in. Long-term stability will also be affected by differential stresses between the IC and the board material created during board assembly. See PC Board Layout in the Applications Information section. Note 9: Hysteresis in output voltage is created by package stress that differs depending on whether the IC was previously at a higher or lower temperature. Output voltage is always measured at 25°C, but the IC is cycled to 85°C or –40°C before successive measurements. Hysteresis is roughly proportional to the square of the temperature change. For instruments that are stored at reasonably well-controlled temperatures (within 20 or 30 degrees of operating temperature) hysteresis is generally not a problem. Note 10: The LT1460S3 is guaranteed functional over the operating temperature range of –40° to 85°C. 1460fc LT1460 Typical Performance Characteristics LT1460-2.5 (N8, S8, MS8, Z Packages) 2.5V Minimum Input-Output Voltage Differential 2.5V Load Regulation, Sourcing –55°C 25°C 125°C 0.5 1.0 1.5 2.0 INPUT-OUTPUT VOLTAGE (V) 0 5 4 3 25°C 2 –55°C 1 0 2.5 125°C 0.1 1 10 OUTPUT CURRENT (mA) 2.5V Output Voltage Temperature Drift 2.503 125°C 75 125 25°C 100 –55°C 75 50 1.0 0.5 OUTPUT CURRENT (mA) 0 0 100 0 5 10 20 15 INPUT VOLTAGE (V) 2.5V Power Supply Rejection Ratio vs Frequency 125°C 2.5006 25°C 2.5002 2.4998 –55°C 2.4990 0 2 4 1460 G05 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) 1460 G06 2.5V Output Impedance vs Frequency 90 1.5 2.4994 1460 G04 POWER SUPPLY REJECTION RATIO (dB) –55°C 10 2.5010 25 2.5V Transient Responses 1k CL= 0.1µF 80 OUTPUT IMPEDANCE (Ω) 70 60 50 40 30 20 10 CL = 0 100 10 10k 100k FREQUENCY (Hz) 1M 1460 G07 1 1 0.1 IOUT = 10mA CL= 1µF 1k 10 0 0 –10 100 20 2.5V Line Regulation OUTPUT VOLTAGE (V) SUPPLY CURRENT (µA) OUTPUT VOLTAGE (V) 2.499 0 25 50 TEMPERATURE (°C) 30 2.5014 150 2.502 2.500 25°C 40 1460 G03 175 3 TYPICAL PARTS –25 50 2.5V Supply Current vs Input Voltage 2.501 125°C 60 1460 G02 1460 G01 2.498 –50 70 0 100 LOAD CAPACITANCE (µF) 1 80 OUTPUT VOLTAGE CHANGE (mV) 10 0.1 2.5V Load Regulation, Sinking 6 OUTPUT VOLTAGE CHANGE (mV) OUTPUT CURRENT (mA) 100 10 100 1k 10k FREQUENCY (Hz) 100k 1460 G09 1M 1460 G08 1460fc LT1460 Typical Performance Characteristics 2.5V Output Voltage Noise Spectrum 2.5V Long-Term Drift Three Typical Parts (S8 Package) 2.5V Output Noise 0.1Hz to 10Hz 1000 2.5000 OUTPUT VOLTAGE (V) NOISE VOLTAGE (nV/√Hz) OUTPUT NOISE (10µV/DIV) 2.4998 100 0 100k 1k 10k FREQUENCY (Hz) 2.4994 2.4992 100 10 2.4996 1 2 3 4 5 6 TIME (SEC) 7 8 9 2.4990 10 200 0 600 400 TIME (HOURS) 800 1460 G11 1460 G10 1000 1460 G12 LT1460-5 (N8, S8, MS8, Z Packages) 5V Minimum Input-Output Voltage Differential 5V Load Regulation, Sourcing 25°C –55°C 1 0.5 1.0 1.5 2.0 INPUT-OUTPUT VOLTAGE (V) 0 90 5 4 125°C 3 25°C 2 –55°C 1 0 2.5 100 80 70 60 40 30 0.1 1 10 OUTPUT CURRENT (mA) 0 100 5.004 1 3 4 2 OUTPUT CURRENT (mA) 3 TYPICAL PARTS 5.002 125°C 180 25°C 160 5.000 25°C 140 120 OUTPUT VOLTAGE (V) SUPPLY CURRENT (µA) 5.002 5 5V Line Regulation 200 –55°C 100 80 60 40 4.996 0 1460 G15 5V Supply Current vs Input Voltage 4.998 125°C 20 1460 G14 5V Output Voltage Temperature Drift 5.000 25°C –55°C 50 10 1460 G13 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE CHANGE (mV) OUTPUT VOLTAGE CHANGE (mV) OUTPUT CURRENT (mA) 125°C 10 0.1 5V Load Regulation, Sinking 6 100 125°C 4.998 4.996 –55°C 4.994 20 4.994 –50 –25 0 25 50 TEMPERATURE (°C) 75 100 1460 G16 0 0 2 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) 1460 G17 4.992 0 2 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) 1460 G18 1460fc LT1460 Typical Performance Characteristics LT1460-5 (N8, S8, MS8, Z Packages) 5V Power Supply Rejection Ratio vs Frequency 5V Output Impedance vs Frequency 5V Transient Responses 1k 80 CL = 0 CL= 0.1µF OUTPUT IMPEDANCE (Ω) 70 60 50 40 30 20 LOAD CAPACITANCE (µF) POWER SUPPLY REJECTION RATIO (dB) 90 100 10 1 10 1 0.1 0 CL= 1µF 10 0 100 1k 10k 100k FREQUENCY (Hz) 0.1 1M 10 100 1460 G19 1k 10k FREQUENCY (Hz) 100k 1460 G21 0.2ms/DIV IOUT = 10mA 1M 1460 G20 5V Output Voltage Noise Spectrum 5V Output Noise 0.1Hz to 10Hz 3000 NOISE VOLTAGE (nV/√Hz) OUTPUT NOISE (10µV/DIV) 2000 1000 100 10 100 1k 10k FREQUENCY (Hz) 0 100k 1 2 3 1460 G22 4 5 6 TIME (SEC) 7 8 9 10 1460 G23 LT1460-10 (N8, S8, MS8, Z Packages) 10V Minimum Input/Output Voltage Differential 10V Load Regulation, Sourcing 10 125°C 1 –55°C 25°C 100 9 90 8 7 6 5 0 0.5 1.0 1.5 2.0 INPUT/OUTPUT VOLTAGE (V) 2.5 1460 G24 125°C 25°C 4 3 2 1 0.1 10V Load Regulation, Sinking 10 OUTPUT VOLTAGE CHANGE (mV) OUTPUT VOLTAGE CHANGE (mV) OUTPUT CURRENT (mA) 100 0 0.1 –55°C 1 10 OUTPUT CURRENT (mA) 80 70 25°C 60 –55°C 50 125°C 40 30 20 10 100 1460 G25 0 0 1 3 4 2 OUTPUT CURRENT (mA) 5 1460 G26 1460fc 10 LT1460 Typical Performance Characteristics 10V Output Voltage Temperature Drift 3 TYPICAL PARTS 360 10.000 320 SUPPLY CURRENT (µA) OUTPUT VOLTAGE (V) 10.002 9.998 9.994 9.990 10V Line Regulation 10.004 400 –55°C 280 240 OUTPUT VOLTAGE (V) 10.006 10V Supply Current vs Input Voltage 25°C 200 125°C 160 120 80 9.986 25°C 9.996 –55°C 9.992 125°C 9.988 9.984 40 –25 0 25 50 TEMPERATURE (°C) 75 0 100 0 2 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) 10V Power Supply Rejection Ratio vs Frequency 14 16 10 12 INPUT VOLTAGE (V) 8 18 20 1460 G29 10V Output Impedance vs Frequency 100 10V Transient Responses 1000 90 CL = 0µF OUTPUT IMPEDANCE (Ω) 80 70 60 50 40 30 20 100 CL = 0.1µF 10 CL = 1µF 1 10 10 1 0.1 0 200µs/DIV IOUT = 10mA 10 100 1 INPUT FREQUENCY (kHz) 1000 0.1 0.01 0.1 1460 G30 1 10 FREQUENCY (kHz) 100 1460 G32 1000 1460 G31 10V Output Voltage Noise Spectrum 10V Output Noise 0.1Hz to 10Hz OUTPUT NOISE (50µV/DIV) 10 NOISE VOLTAGE (µV/√Hz) POWER SUPPLY REJECTION RATIO (dB) 6 1460 G28 1460 G27 0 0.1 9.980 LOAD CAPACITANCE (µF) 9.982 –50 1 0.1 0.01 0.1 1 10 FREQUENCY (kHz) 100 1460 G33 0 2 4 6 8 10 TIME (SEC) 12 14 1460 G34 1460fc 11 LT1460 Typical Performance Characteristics Characteristic curves are similar for all voltage options of the LT1460S3. Curves from the LT1460S3-2.5 and the LT1460S3-10 represent the extremes of the voltage options. Characteristic curves for other output voltages fall between these curves, and can be estimated based on their voltage output. LT1460S3-2.5V Minimum InputOutput Voltage Differential LT1460S3-2.5V Load Regulation, Sourcing 0 125°C 25°C –55°C 1 0.5 1.0 1.5 2.0 INPUT-OUTPUT VOLTAGE (V) 0 –0.5 –1.0 –55°C –1.5 –2.0 25°C –2.5 125°C –3.0 –3.5 –4.0 0.1 2.5 1 10 OUTPUT CURRENT (mA) SUPPLY CURRENT (µA) OUTPUT VOLTAGE (V) 2.500 2.499 50 25 75 0 TEMPERATURE (°C) 100 –55°C 100 0 125 0 1 5 2 3 4 OUTPUT CURRENT (mA) 25°C 2.500 –55°C 2.499 2.498 125°C 2.497 2.496 2.495 5 0 10 15 INPUT VOLTAGE (V) 1460 G38 20 2.494 0 2 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) 1460 G40 1460 G39 LT1460S3-2.5V Output Impedance vs Frequency 80 LT1460S3-2.5V Transient Response 1000 CL = 0µF 70 60 OUTPUT IMPEDANCE (Ω) POWER SUPPLY REJECTION RATIO (dB) 125°C 150 LT1460S3-2.5V Power Supply Rejection Ratio vs Frequency 50 40 30 20 20 CL = 0.1µF 100 10 CL = 1µF 10 1 0.1 1 10 0 0.1 20 2.501 50 2.498 –55°C LT1460S3-2.5V Line Regulation 25°C 200 2.501 125°C 2.502 250 2.502 25°C 40 LT1460S3-2.5V Supply Current vs Input Voltage THREE TYPICAL PARTS 2.497 –50 –25 60 1460 G37 LOAD CURRENT (mA) 2.503 80 1460 G36 1460 G35 LT1460S3-2.5V Output Voltage Temperature Drift 100 0 100 OUTPUT VOLTAGE (V) 10 120 OUTPUT VOLTAGE CHANGE (mV) OUTPUT VOLTAGE CHANGE (mV) OUTPUT CURRENT (mA) 100 0.1 LT1460S3-2.5V Load Regulation, Sinking CLOAD = 0µF 1 10 100 FREQUENCY (kHz) 1000 1460 G41 0.1 0.01 0.1 1 10 FREQUENCY (kHz) 100 200µs/DIV 1460 G43 1000 1460 G42 1460fc 12 LT1460 Typical Performance Characteristics Characteristic curves are similar for all voltage options of the LT1460S3. Curves from the LT1460S3-2.5 and the LT1460S3-10 represent the extremes of the voltage options. Characteristic curves for other output voltages fall between these curves, and can be estimated based on their voltage output. LT1460S3-2.5V Output Voltage Noise Spectrum 1000 LT1460S3-2.5V Output Noise 0.1Hz to 10Hz LT1460S3-10V Minimum InputOutput Voltage Differential OUTPUT CURRENT (mA) NOISE VOLTAGE (nV/√Hz) OUTPUT NOISE (20µV/DIV) 100 100 10 100 25°C –55°C 1 0.1 TIME (2 SEC/DIV) 100k 1k 10k FREQUENCY (Hz) 125°C 10 0.5 1.0 1.5 2.0 INPUT-OUTPUT VOLTAGE (V) 0 1460 G45 1460 G46 1460 G44 LT1460S3-10V Load Regulation, Sourcing LT1460S3-10V Load Regulation, Sinking 15 10 5 –55°C 0 –5 125°C 150 25°C 100 –55°C 50 9.998 9.996 9.994 9.992 9.990 9.988 9.986 9.984 100 0 0 1 3 4 2 OUTPUT CURRENT (mA) 5 9.982 –50 –25 50 0 75 25 TEMPERATURE (°C) LT1460S3-10V Supply Current vs Input Voltage 100 125 1460 G49 1460 G48 1460 G47 LT1460S3-10V Line Regulation 10.010 350 300 250 125°C 200 –55°C 150 100 OUTPUT VOLTAGE (V) 10.005 25°C 25°C 10.000 –55°C 9.995 125°C 9.990 9.985 50 0 10.000 125°C 25°C 1 10 OUTPUT CURRENT (mA) THREE TYPICAL PARTS 10.002 200 OUTPUT VOLTAGE (V) OUTPUT VOLTAGE CHANGE (mV) 20 SUPPLY CURRENT (µA) OUTPUT VOLTAGE CHANGE (mV) 10.006 10.004 25 –10 0.1 LT1460S3-10V Output Voltage Temperature Drift 250 35 30 2.5 0 2 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) 1460 G50 9.980 6 8 14 12 16 10 INPUT VOLTAGE (V) 18 20 1460 G51 1460fc 13 LT1460 Typical Performance Characteristics Characteristic curves are similar for all voltage options of the LT1460S3. Curves from the LT1460S3-2.5 and the LT1460S3-10 represent the extremes of the voltage options. Characteristic curves for other output voltages fall between these curves, and can be estimated based on their voltage output. LT1460S3-10V Output Impedance vs Frequency LT1460S3-10V Transient Response 1000 90 20 70 60 50 40 30 20 100 LOAD CURRENT (mA) CL = 0µF 80 OUTPUT IMPEDANCE (Ω) POWER SUPPLY REJECTION RATIO (dB) 100 LT1460S3-10V Power Supply Rejection Ratio vs Frequency CL = 0.1µF 10 CL = 1µF 1 1 0.1 10 0 0.1 10 CLOAD = 0µF 1 10 100 FREQUENCY (kHz) 1000 0.1 0.01 0.1 1460 G52 1 10 FREQUENCY (kHz) 100 200µs/DIV 1460 G54 1000 1460 G53 LT1460S3-10V Output Voltage Noise Spectrum LT1460S3-10V Output Noise 0.1Hz to 10Hz OUTPUT NOISE (20µV/DIV) NOISE VOLTAGE (µV/√Hz) 10 1 0.1 0.01 0.1 1 10 FREQUENCY (kHz) 100 TIME (2 SEC/DIV) 1460 G56 1460 G55 1460fc 14 LT1460 Applications Information Longer Battery Life Series references have a large advantage over older shunt style references. Shunt references require a resistor from the power supply to operate. This resistor must be chosen to supply the maximum current that can ever be demanded by the circuit being regulated. When the circuit being controlled is not operating at this maximum current, the shunt reference must always sink this current, resulting in high dissipation and short battery life. the ringing can be reduced with a small resistor in series with the reference output as shown in Figure 4. Figure 5 shows the response of the LT1460-2.5 with a RS = 2Ω and 1.5V The LT1460 series reference does not require a current setting resistor and can operate with any supply voltage from VOUT + 0.9V to 20V. When the circuitry being regulated does not demand current, the LT1460 reduces its dissipation and battery life is extended. If the reference is not delivering load current it dissipates only a few mW, yet the same configuration can deliver 20mA of load current when demanded. RL = 10k VOUT RL = 1k 1460 F02 Figure 2. CL = 0 2.5V VGEN 1.5V The LT1460 is designed to be stable with capacitive loads. With no capacitive load, the reference is ideal for fast settling, applications where PC board space is a premium, or where available capacitance is limited. The test circuit for the LT1460-2.5 shown in Figure 1 is used to measure the response time for various load currents and load capacitors. The 1V step from 2.5V to 1.5V produces a current step of 1mA or 100µA for RL = 1k or RL = 10k. Figure 2 shows the response of the reference with no load capacitance. The reference settles to 2.5mV (0.1%) in less than 1µs for a 100µA pulse and to 0.1% in 1.5µs with a 1mA step. When load capacitance is greater than 0.01µF, the reference begins to ring due to the pole formed with the output impedance. Figure 3 shows the response of the reference to a 1mA and 100µA load current step with a 0.01µF load capacitor. The ringing can be greatly reduced with a DC load as small as 200µA. With large output capacitors, ≥1µF, CIN 0.1µF VOUT 1µs/DIV Capacitive Loads VIN = 5V 2.5V VGEN LT1460-2.5 RL VOUT VGEN CL RL = 10k VOUT RL = 1k 1460 F03 20µs/DIV Figure 3. CL = 0.01µF VIN = 5V LT1460-2.5 RS VOUT RL VGEN CIN 0.1µF 2.5V 1.5V CL 1460 F04 Figure 4. Isolation Resistor Test Circuit VGEN 2.5V 1.5V VOUT RL = 1k RS = 0 VOUT RL = 1k RS = 2Ω 2.5V 1.5V 1460 F01 Figure 1. Response Time Test Circuit VOUT 0.1ms/DIV 1460 F05 Figure 5. Effect of RS for CL = 1µF 1460fc 15 LT1460 Applications Information CL = 1µF. RS should not be made arbitrarily large because it will limit the load regulation. Figure 6 to Figure 8 illustrate response in the LT1460-5. The 1V step from 5V to 4V produces a current step of 1mA or 100µA for RL = 1k or RL = 10k. Figure 7 shows the response of the reference with no load capacitance. The reference settles to 5mV (0.1%) in less than 2µs for a 100µA pulse and to 0.1% in 3µs with a 1mA step. When load capacitance is greater than 0.01µF, the reference begins to ring due to the pole formed with the output impedance. Figure 8 shows the response of the reference to a 1mA VIN = 5V LT1460-5 RL VOUT CIN 0.1µF and 100µA load current step with a 0.01µF load capacitor. Figure 9 to Figure 11 illustrate response of the LT1460-10. The 1V step from 10V to 9V produces a current step of 1mA or 100µA for RL = 1k or RL = 10k. Figure 10 shows the response of the reference with no load capacitance. The reference settles to 10mV (0.1%) in 0.4µs for a 100µA pulse and to 0.1% in 0.8µs with a 1mA step. When load capacitance is greater than 0.01µF, the reference begins to ring due to the pole formed with the output impedance. Figure 11 shows the response of the reference to a 1mA and 100µA load current step with a 0.01µF load capacitor. VIN = 12.5V VGEN 5V 4V CL LT1460-10 RL VOUT CIN 0.1µF VGEN 1460 F09 1460 F06 Figure 9. Response Time Test Circuit Figure 6. Response Time Test Circuit 5V VGEN 10V VGEN 4V VOUT RL = 10k VOUT RL = 1k 2µs/DIV 9V VOUT RL = 10k VOUT 1460 F07 RL = 1k 2µs/DIV Figure 7. CL = 0 1460 F10 Figure 10. CL = 0 VGEN 10V 5V 4V VOUT RL = 10k VOUT RL = 1k 10µs/DIV Figure 8. CL = 0.01µF 10V 9V CL 1460 F08 VGEN 9V VOUT RL = 10k RL = 1k VOUT 10µs/DIV 1460 F11 Figure 11. CL = 0.01µF 1460fc 16 LT1460 Applications Information The LT1460S3 family of references are designed to be stable with a large range of capacitive loads. With no capacitive load, these references are ideal for fast settling or applications where PC board space is a premium. The test circuit shown in Figure 12 is used to measure the response time and stability of various load currents and load capacitors. This circuit is set for the 2.5V option. For other voltage options, the input voltage must be scaled up and the output voltage generator offset voltage must be adjusted. The 1V step from 2.5V to 1.5V produces a current step of 10mA or 1mA for RL = 100Ω or RL = 1k. Figure 13 shows the response of the reference to these VIN = 2.5V LT1460S3-2.5 RL VOUT CIN 0.1µF VGEN CL 1mA and 10mA load steps with no load capacitance, and Figure 14 shows a 1mA and 10mA load step with a 0.1µF output capacitor. Figure 15 shows the response to a 1mA load step with CL = 1µF and 4.7µF. The frequency compensation of the LT1460S3 version is slightly different than that of the other packages. Additional care must be taken when choosing load capacitance in an application circuit. Table 1 gives the maximum output capacitance for various load currents and output voltages of the LT1460S3 to avoid instability. Load capacitors with low ESR (effective series resistance) cause more ringing than capacitors with higher ESR such as polarized aluminum or tantalum capacitors. 2.5V 1.5V 1460 F12 VGEN Figure 12. Response Time Test Circuit VGEN 2.5V 1.5V 2.5V 1.5V VOUT 1mA VOUT 10mA VOUT 1mA VOUT 10mA 100µs/DIV 1µs/DIV Figure 13. CL = 0µF 1460 F14 Figure 14. CL = 0.1µF 1460 F13 VGEN 2.5V 1.5V VOUT 1µA VOUT 4.7µA 100µs/DIV 1460 F15 Figure 15. IOUT = 1mA 1460fc 17 LT1460 Applications Information Hysteresis VOLTAGE OPTION IOUT = 100µA IOUT = 1mA 2.5V >10µF >10µF 2µF 0.68µF 3V >10µF >10µF 2µF 0.68µF 3.3V >10µF >10µF 1µF 0.68µF 5V >10µF >10µF 1µF 0.68µF 10V >10µF 1µF 0.15µF 0.1µF IOUT = 10mA IOUT = 20mA Long-Term Drift Long-term drift cannot be extrapolated from accelerated high temperature testing. This erroneous technique gives drift numbers that are wildly optimistic. The only way long-term drift can be determined is to measure it over the time interval of interest. The LT1460S3 long-term drift data was taken on over 100 parts that were soldered into PC boards similar to a “real world” application. The boards were then placed into a constant temperature oven with TA = 30°C, their outputs were scanned regularly and measured with an 8.5 digit DVM. Figure 16 shows typical long-term drift of the LT1460S3s. Hysteresis data shown in Figure 17 and Figure 18 represents the worst-case data taken on parts from 0°C to 70°C and from –40°C to 85°C. The device is capable of dissipating relatively high power, i.e., for the LT1460S3-2.5, PD = 17.5V • 20mA = 350mW. The thermal resistance of the SOT-23 package is 325°C/W and this dissipation causes a 114°C internal rise producing a junction temperature of TJ = 25°C + 114°C = 139°C. This elevated temperature will cause the output to shift due to thermal hysteresis. For highest performance in precision applications, do not let the LT1460S3’s junction temperature exceed 85°C. 18 16 WORST-CASE HYSTERESIS ON 40 UNITS 14 NUMBER OF UNITS Table 1. Maximum Output Capacitance for LT1460S3 12 10 8 70°C TO 25°C 0°C TO 25°C 6 4 2 150 0 100 ppm 80 120 160 200 240 1460 F17 Figure 17. 0°C to 70°C Hysteresis 50 0 9 8 –50 0 100 200 300 400 500 600 700 800 900 1000 HOURS 1460 F16 Figure 16. Typical Long-Term Drift NUMBER OF UNITS 7 –100 –150 40 –240 –200 –160 –120 –80 –40 0 HYSTERESIS (ppm) 6 WORST-CASE HYSTERESIS ON 34 UNITS 85°C TO 25°C –40°C TO 25°C 5 4 3 2 1 0 –600 –500 –400 –300 –200 –100 0 100 200 300 400 500 600 HYSTERESIS (ppm) 1460 F18 Figure 18. –40°C to 85°C Hysteresis 1460fc 18 LT1460 Applications Information Input Capacitance Total worst-case output error is: It is recommended that a 0.1µF or larger capacitor be added to the input pin of the LT1460. This can help with stability when large load currents are demanded. 0.075% + 0.035% + 0.070% = 0.180%. Output Accuracy Like all references, either series or shunt, the error budget of the LT1460-2.5 is made up of primarily three components: initial accuracy, temperature coefficient and load regulation. Line regulation is neglected because it typically contributes only 30ppm/V, or 75µV for a 1V input change. The LT1460-2.5 typically shifts less than 0.01% when soldered into a PCB, so this is also neglected (see PC Board Layout section). The output errors are calculated as follows for a 100µA load and 0°C to 70°C temperature range: LT1460AC Initial accuracy = 0.075% For IO = 100µA, and using the LT1460-2.5 for calculation, 3500ppm ΔVOUT = 0.1mA 2.5V = 875µV mA ( )( ) which is 0.035%. For temperature 0°C to 70°C the maximum ΔT = 70°C, 10ppm ΔVOUT = 70°C 2.5V = 1.75mV °C ( )( ) Table 1 gives worst-case accuracy for the LT1460AC, CC, DC, FC, GC from 0°C to 70°C and the LT1460BI, EI, GI from –40°C to 85°C. Note that the LT1460-5 and LT1460-10 give identical accuracy as a fraction of their respective output voltages. PC Board Layout In 13- to 16-bit systems where initial accuracy and temperature coefficient calibrations have been done, the mechanical and thermal stress on a PC board (in a cardcage for instance) can shift the output voltage and mask the true temperature coefficient of a reference. In addition, the mechanical stress of being soldered into a PC board can cause the output voltage to shift from its ideal value. Surface mount voltage references (MS8 and S8) are the most susceptible to PC board stress because of the small amount of plastic used to hold the lead frame. A simple way to improve the stress-related shifts is to mount the reference near the short edge of the PC board, or in a corner. The board edge acts as a stress boundary, or a region where the flexure of the board is minimum. The package should always be mounted so that the leads absorb the stress and not the package. The package is generally aligned with the leads parallel to the long side of the PC board as shown in Figure 20a. A qualitative technique to evaluate the effect of stress on voltage references is to solder the part into a PC board and which is 0.07%. Table 2. Worst-Case Output Accuracy Over Temperature IOUT LT1460AC LT1460BI LT1460CC LT1460DC LT1460EI LT1460FC LT1460GC LT1460GI LT1460HC LT1460JC LT1460KC 0 0.145% 0.225% 0.205% 0.240% 0.375% 0.325% 0.425% 0.562% 0.340% 0.540% 0.850% 100µA 0.180% 0.260% 0.240% 0.275% 0.410% 0.360% 0.460% 0.597% 0.380% 0.580% 0.890% 10mA 0.325% 0.405% 0.385% 0.420% 0.555% 0.505% 0.605% 0.742% 0.640% 0.840% 1.15% 20mA 0.425% N/A 0.485% 0.520% N/A 0.605% 0.705% N/A 0.540% 0.740% 1.05% 1460fc 19 LT1460 Applications Information deform the board a fixed amount as shown in Figure 19. The flexure #1 represents no displacement, flexure #2 is concave movement, flexure #3 is relaxation to no displacement and finally, flexure #4 is a convex movement. This motion is repeated for a number of cycles and the relative output deviation is noted. The result shown in Figure 20a is for two LT1460S8-2.5s mounted vertically and Figure 20b is for two LT1460S8-2.5s mounted horizontally. The parts oriented in Figure 20a impart less stress into the package because stress is absorbed in the leads. Figures 20a and 20b show the deviation to be between 125µV and 1 2 The most effective technique to improve PC board stress is to cut slots in the board around the reference to serve as a strain relief. These slots can be cut on three sides of the reference and the leads can exit on the fourth side. This “tongue” of PC board material can be oriented in the long direction of the board to further reduce stress transferred to the reference. The results of slotting the PC boards of Figures 20a and 20b are shown in Figures 21a and 21b. In this example the slots can improve the output shift from about 100ppm to nearly zero. 3 4 250µV and implies a 50ppm and 100ppm change respectively. This corresponds to a 13- to 14-bit system and is not a problem for most 10- to 12-bit systems unless the system has a calibration. In this case, as with temperature hysteresis, this low level can be important and even more careful techniques are required. 1460 F19 Figure 19. Flexure Numbers 2 OUTPUT DEVIATION (mV) OUTPUT DEVIATION (mV) 2 1 LONG DIMENSION 0 –1 0 10 20 30 FLEXURE NUMBER 1 –1 40 LONG DIMENSION 0 0 1460 F20a 30 40 1460 F20b Figure 20b. Two Typical LT1460S8-2.5s, Horizontal Orientation Without Slots 2 OUTPUT DEVIATION (mV) 2 OUTPUT DEVIATION (mV) 20 FLEXURE NUMBER Figure 20a. Two Typical LT1460S8-2.5s, Vertical Orientation Without Slots 1 0 SLOT –1 10 0 10 20 30 FLEXURE NUMBER Figure 21a. Same Two LT1460S8-2.5s in Figure 16a, but with Slots 20 40 1460 F21a 1 0 SLOT –1 0 10 20 30 FLEXURE NUMBER Figure 21b. Same Two LT1460S8-2.5s in Figure 16b, but with Slots 40 1460 F21b 1460fc LT1460 Simplified Schematic VCC VOUT GND 1460 SS Package Description S3 Package 3-Lead Plastic SOT-23 (Reference LTC DWG # 05-08-1631) 0.764 2.80 – 3.04 (.110 – .120) 0.8 ±0.127 2.10 – 2.64 (.083 – .104) 2.74 1.20 – 1.40 (.047 – .060) 0.96 BSC 1.92 0.45 – 0.60 (.017 – .024) 0.89 – 1.03 (.035 – .041) RECOMMENDED SOLDER PAD LAYOUT 0.37 – 0.51 (.015 – .020) 0.89 – 1.12 (.035 – .044) 0.55 (.022) REF NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) 0.09 – 0.18 (.004 – .007) 0.01 – 0.10 (.0004 – .004) 1.78 – 2.05 (.070 – .081) S3 SOT-23 0502 3. DRAWING NOT TO SCALE 4. DIMENSIONS ARE INCLUSIVE OF PLATING 5. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 6. MOLD FLASH SHALL NOT EXCEED .254mm 7. PACKAGE JEDEC REFERENCE IS TO-236 VARIATION AB 1460fc 21 LT1460 Package Description N8 Package 8-Lead PDIP (Narrow .300 Inch) (Reference LTC DWG # 05-08-1510) .400* (10.160) MAX 8 7 6 5 1 2 3 4 .255 ± .015* (6.477 ± 0.381) .300 – .325 (7.620 – 8.255) .065 (1.651) TYP .008 – .015 (0.203 – 0.381) ( +.035 .325 –.015 8.255 +0.889 –0.381 .130 ± .005 (3.302 ± 0.127) .045 – .065 (1.143 – 1.651) ) .120 (3.048) .020 MIN (0.508) MIN .018 ± .003 .100 (2.54) BSC (0.457 ± 0.076) N8 1002 NOTE: 1. DIMENSIONS ARE INCHES MILLIMETERS *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .010 INCH (0.254mm) S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610) .050 BSC .189 – .197 (4.801 – 5.004) NOTE 3 .045 ±.005 8 .245 MIN .160 ±.005 .010 – .020 × 45° (0.254 – 0.508) NOTE: 1. DIMENSIONS IN 5 .150 – .157 (3.810 – 3.988) NOTE 3 1 RECOMMENDED SOLDER PAD LAYOUT .053 – .069 (1.346 – 1.752) 0°– 8° TYP .016 – .050 (0.406 – 1.270) 6 .228 – .244 (5.791 – 6.197) .030 ±.005 TYP .008 – .010 (0.203 – 0.254) 7 .014 – .019 (0.355 – 0.483) TYP INCHES (MILLIMETERS) 2. DRAWING NOT TO SCALE 3. THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 2 3 4 .004 – .010 (0.101 – 0.254) .050 (1.270) BSC SO8 0303 1460fc 22 LT1460 Package Description MS8 Package 8-Lead Plastic MSOP (Reference LTC DWG # 05-08-1660 Rev F) 0.889 ± 0.127 (.035 ± .005) 5.23 (.206) MIN 3.20 – 3.45 (.126 – .136) 3.00 ± 0.102 (.118 ± .004) (NOTE 3) 0.65 (.0256) BSC 0.42 ± 0.038 (.0165 ± .0015) TYP 8 7 6 5 0.52 (.0205) REF RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) 3.00 ± 0.102 (.118 ± .004) (NOTE 4) 4.90 ± 0.152 (.193 ± .006) DETAIL “A” 0° – 6° TYP GAUGE PLANE 0.53 ± 0.152 (.021 ± .006) DETAIL “A” 1 2 3 4 1.10 (.043) MAX 0.86 (.034) REF 0.18 (.007) SEATING PLANE 0.22 – 0.38 (.009 – .015) TYP 0.65 (.0256) BSC 0.1016 ± 0.0508 (.004 ± .002) MSOP (MS8) 0307 REV F NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 5. LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 1460fc 23 LT1460 Package Description Z Package 3-Lead Plastic TO-92 (Similar to TO-226) (Reference LTC DWG # 05-08-1410 Rev C) .060 p .005 (1.524p 0.127) DIA .180 p .005 (4.572 p 0.127) .90 (2.286) NOM .180 p .005 (4.572 p 0.127) .500 (12.70) MIN .050 (1.27) BSC .050 UNCONTROLLED (1.270) LEAD DIMENSION MAX .016 p .003 (0.406 p 0.076) BULK PACK .060 p .010 (1.524 p 0.254) 3 2 1 5o NOM .015 p .002 (0.381 p 0.051) Z3 (TO-92) 1008 REV C .098 +.016/–.04 (2.5 +0.4/–0.1) 2 PLCS TO-92 TAPE AND REEL REFER TO TAPE AND REEL SECTION OF LTC DATA BOOK FOR ADDITIONAL INFORMATION .140 p .010 (3.556 p 0.127) 10o NOM 1460fc 24 LT1460 Revision History (Revision history begins at Rev C) REV DATE DESCRIPTION PAGE NUMBER C 3/10 Change θJA on S3 Package from 325°C/W to 228°C/W 2 1460fc Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 25 LT1460 Typical Applications Handling Higher Load Currents V+ + 47µF 40mA IN R1* LT1460 10mA VOUT OUT GND RL TYPICAL LOAD CURRENT = 50mA *SELECT R1 TO DELIVER 80% OF TYPICAL LOAD CURRENT. LT1460 WILL THEN SOURCE AS NECESSARY TO MAINTAIN PROPER OUTPUT. DO NOT REMOVE LOAD AS OUTPUT WILL BE DRIVEN UNREGULATED HIGH. LINE REGULATION IS DEGRADED IN THIS APPLICATION Boosted Output Current with No Current Limit V+ ≥ (VOUT + 1.8V) V+ – VOUT 40mA 1460 TA03 Boosted Output Current with Current Limit V+ ≥ VOUT + 2.8V + R1 220Ω R1 = D1* LED 47µF + R1 220Ω 8.2Ω 2N2905 47µF 2N2905 IN IN LT1460 OUT GND + 2µF SOLID TANT LT1460 VOUT 100mA OUT GND 1460 TA04 + 2µF SOLID TANT VOUT 100mA * GLOWS IN CURRENT LIMIT, DO NOT OMIT 1460 TA05 Related Parts PART NUMBER DESCRIPTION COMMENTS LT1019 Precision Bandgap Reference 0.05% Max, 5ppm/°C Max LT1027 Precision 5V Reference 0.02%, 2ppm/°C Max LT1236 Precision Low Noise Reference 0.05% Max, 5ppm/°C Max, SO Package LT1461 Micropower Precision Low Dropout 0.04% Max, 3ppm/°C Max, 50mA Output Current LT1634 Micropower Precision Shunt Reference 1.25V, 2.5V Output 0.05%, 25ppm/°C Max LT1790 Micropower Precision Series References 0.05% Max, 10ppm/°C Max, 60µA Supply, SOT23 Package LTC®1798 Micropower Low Dropout Reference, Fixed or Adjustable 0.15% Max, 40ppm/°C, 6.5µA Max Supply Current LTC6652 Low Drift Low Noise Buffered Reference 0.05% Accuracy, 5ppm/°C Drift, 2.1ppm (0.1Hz to 10Hz) Noise LT6660 Tiny Micropower Precision Series References 0.075% Max, 10ppm/°C Max, 20mA Output, 2mm × 2mm DFN Package 1460fc 26 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LT 0310 REV C • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2006