LT1019

LT1019 Precision Reference FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Tight Initial Output Voltage: < 0.05% Ultralow Drift: 3ppm/°C Typical Series or Shunt Operation Curvature Corrected Ultrahigh Line Rejection: ≈ 0.5ppm/V Low Output Impedance: ≈ 0.02Ω Plug-In Replacement for Present References Available at 2.5V, 4.5V, 5V, and 10V 100% Noise Tested Temperature Output Industrial Temperature Range in SO-8 Available in 8-Lead N8 and S8 Packages The LT ®1019 is a third generation bandgap voltage reference utilizing thin film technology and a greatly improved curvature correction technique. Wafer level trimming of both reference and output voltage combines to produce very low TC and tight initial output voltage tolerance. The LT1019 can both sink and source up to 10mA and can be used in either the series or shunt mode, allowing the reference to operate with positive or negative output voltages without external components. Minimum input/ output voltage is less than 1V in the series mode, providing improved tolerance of low line conditions and excellent line regulation. The LT1019 is available in four voltages: 2.5V, 4.5V, 5V and 10V. It is a direct replacement for most bandgap references presently available including AD580, AD581, REF-01, REF-02, MC1400, MC1404 and LM168. , LTC and LT are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. APPLICATIO S ■ ■ ■ ■ ■ ■ Negative Shunt References A/D and D/A Converters Precision Regulators Constant Current Sources V/F Converters Bridge Excitation TYPICAL APPLICATION Ultralinear Strain Gauge 15V 357Ω* 0.5W IN OUT 350Ω BRIDGE GND R2 20k R4 20k ACTIVE ELEMENT 5V R3 2M OUTPUT VOLTAGE (NORMALIZED) (V) LT1019-5 + A1† LT1637 A2 LT1001 GAIN = 100 – R5 2M R6** 2M LT1019 • TA01 –5V 357Ω* 0.5W –15V *REDUCES REFERENCE AND AMPLIFIER LOADING TO ≈ 0. **IF R6 = R3, BRIDGE IS NOT LOADED BY R2 AND R4. † A1 VOS AND DRIFT ARE NOT CRITICAL BECAUSE A2 ACTS AS A DIFFERENTIAL AMPLIFIER. U Output Voltage Drift 1.003 1.002 1.001 1.000 0.999 0.998 0.997 –50 –25 LT1019 CURVE 10ppm/°C FULL TEMP RANGE “BOX” 5ppm/°C 0°C TO 70°C “BOX” UNCOMPENSATED “STANDARD” BANDGAP DRIFT CURVE 50 25 75 0 TEMPERATURE (˚C) 100 125 1019 TA02 + – U U 1019fd 1 LT1019 ABSOLUTE AXI U RATI GS Input Voltage .......................................................... 40V Output Voltage (Note 2) LT1019-5, LT1019-10 ........................................ 16V LT1019-2.5, LT1019-4.5 ...................................... 7V Output Short-Circuit Duration (Note 2) VIN < 20V .................................................... Indefinite 20V ≤ VIN ≤ 35V ............................................. 10 sec PACKAGE/ORDER I FOR ATIO TOP VIEW DNC* 8 DNC* 1 INPUT 2 TEMP 3 4 GND (CASE) H PACKAGE 8-LEAD TO-5 METAL CAN *INTERNALLY CONNECTED. DO NOT CONNECT EXTERNALLY 5 7 DNC* 6 OUTPUT TRIM DNC* 1 INPUT 2 TEMP 3 GND 4 N8 PACKAGE 8-LEAD PDIP *INTERNALLY CONNECTED. DO NOT CONNECT EXTERNALLY. TJMAX = 100°C, θJA = 130°C/ W TJMAX = 150°C, θJA = 150°C/ W, θJC = 45°C/W ORDER PART NUMBER LT1019ACH-2.5 LT1019ACH-4.5 LT1019ACH-5 LT1019ACH-10 LT1019AMH-2.5 LT1019AMH-4.5 LT1019AMH-5 LT1019AMH-10 LT1019CH-2.5 LT1019CH-4.5 LT1019CH-5 LT1019CH-10 LT1019MH-2.5 LT1019MH-4.5 LT1019MH-5 LT1019MH-10 LT1019ACN8-2.5 LT1019ACN8-4.5 LT1019ACN8-5 LT1019ACN8-10 LT1019CN8-2.5 LT1019CN8-4.5 OBSOLETE CONSIDER THE N8 OR S8 FOR ALTERNATE SOURCES. 2 U U W WW U W (Note 1) Specified Temperature Range Commercial ............................................. 0°C to 70°C Industrial ............................................ – 40°C to 85°C Military ............................................. – 55°C to 125°C Trim Pin Voltage ................................................... ± 30V Temp Pin Voltage ..................................................... 5V Storage Temperature Range (Note 11) – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C TOP VIEW 8 7 6 5 DNC* DNC* OUTPUT TRIM DNC* 1 INPUT 2 TEMP 3 GND 4 TOP VIEW 8 7 6 5 DNC* DNC* OUTPUT TRIM S8 PACKAGE 8-LEAD PLASTIC SO *INTERNALLY CONNECTED. DO NOT CONNECT EXTERNALLY. TJMAX = 100°C, θJA = 130°C/ W ORDER PART NUMBER LT1019CN8-5 LT1019CN8-10 LT1019IN8-2.5 LT1019IN8-4.5 LT1019IN8-5 LT1019IN8-10 ORDER PART NUMBER LT1019ACS8-2.5 LT1019ACS8-5 LT1019AIS8-2.5 LT1019AIS8-5 LT1019CS8-2.5 LT1019CS8-4.5 LT1019CS8-5 LT1019CS8-10 LT1019IS8-2.5 LT1019IS8-5 S8 PART MARKING 019A25 1019A5 19AI25 019AI5 1925 1945 1905 1910 19I25 19I05 1019fd LT1019 AVAILABLE OPTIO S OUTPUT VOLTAGE (V) 2.5 TEMPERATURE (°C) 0 to 70 – 40 to 85 – 55 to 125 4.5 0 to 70 – 40 to 85 – 55 to 125 5 0 to 70 – 40 to 85 – 55 to 125 10 0 to 70 – 40 to 85 – 55 to 125 ACCURACY (%) 0.05 0.2 0.05 0.2 0.05 0.2 0.05 0.2 0.2 0.05 0.2 0.05 0.2 0.05 0.2 0.05 0.2 0.05 0.2 0.2 0.05 0.2 TEMPERATURE COEFFICIENT (ppm/°C) 5 20 10 20 10 25 5 20 20 10 25 5 20 10 20 10 25 5 20 20 10 25 LT1019AMH-10 LT1019MH-10 LT1019AMH-5 LT1019MH-5 LT1019ACH-10 LT1019CH-10 LT1019CS8-10 LT1019ACN8-10 LT1019CN8-10 LT1019IN8-10 LT1019AMH-4.5 LT1019MH-4.5 LT1019ACH-5 LT1019CH-5 LT1019ACS8-5 LT1019CS8-5 LT1019AIS8-5 LT1019IS8-5 LT1019ACN8-5 LT1019CN8-5 LT1019IN8-5 LT1019AMH-2.5 LT1019MH-2.5 LT1019ACH-4.5 LT1019CH-4.5 LT1019CS8-4.5 LT1019ACN8-4.5 LT1019CN8-4.5 LT1019IN8-4.5 TO-5 H8 LT1019ACH-2.5 LT1019CH-2.5 PACKAGE TYPE SO-8 S8 LT1019ACS8-2.5 LT1019CS8-2.5 LT1019AIS8-2.5 LT1019IS8-2.5 PDIP-8 N8 LT1019ACN8-2.5 LT1019CN8-2.5 LT1019IN8-2.5 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. VIN = 15V, IOUT = 0 unless otherwise noted. SYMBOL TC PARAMETER Output Voltage Tolerance Output Voltage Temperature Coefficient (Note 3) Line Regulation (Note 4) Ripple Rejection LT1019C (0°C to 70°C) LT1019I (– 40°C to 85°C) LT1019M (– 55°C to 125°C) (VOUT + 1.5V) ≤ VIN ≤ 40V ● ● ● ● ∆VOUT ∆VIN RR U CONDITIONS MIN LT1019A TYP MAX 0.02 3 3 5 0.5 1.0 0.05 5 10 10 3 5 MIN LT1019 TYP 0.02 5 5 8 0.5 1.0 MAX 0.2 20 20 25 3 5 UNITS % ppm/°C ppm/°C ppm/°C ppm/V ppm/V dB dB 50Hz ≤ f ≤ 400Hz ● 90 84 110 90 84 110 1019fd 3 LT1019 ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are TA = 25°C. VIN = 15V, IOUT = 0 unless otherwise noted. SYMBOL ∆VOUT ∆IOUT PARAMETER Load Regulation Series Mode (Notes 4, 5) Load Regulation, Shunt Mode Thermal Regulation (Note 7) IQ Quiescent Current Series Mode Minimum Shunt Current Minimum Input/Output Voltage Differential Trim Range (Note 8) IOUT ≤ 1mA IOUT = 10mA LT1019-2.5 LT1019-5 LT1019-10 2V ≤ VIN ≤ 35V ● CONDITIONS 0 ≤ IOUT ≤ 10mA (Note 5) ● MIN LTC1019A TYP MAX 0.02 0.05 0.08 0.4 0.8 0.5 1.0 1.3 0.8 1.1 1.3 MIN LTC1019 TYP MAX 0.02 0.05 0.08 0.4 0.8 0.5 1.2 1.5 0.8 1.1 1.3 UNITS mV/mA (Ω) mV/mA (Ω) mV/mA (Ω) mV/mA (Ω) ppm/mW mA mA mA V V % % % 1mA ≤ ISHUNT ≤ 10mA (Notes 5, 6) 2.5V, 4.5V, 5V 10V ∆P = 200mW, t = 50ms ● ● 0.1 0.1 0.65 0.1 0.1 0.65 0.5 0.9 ± 3.5 ± 3.5 ± 3.5 ±6 5, – 13 5, – 27 25 2.5 2.5 ● ● ● ● 0.5 0.9 ± 3.5 ±6 ± 3.5 5, – 13 ± 3.5 5, – 27 15 10 25 2.5 2.5 ISC en Short-Circuit Current Output Connected to GND Output Voltage Noise (Note 10) 50 4 15 10 50 4 mA mA ppm (RMS) ppm (P-P) 10Hz ≤ f ≤ 1kHz 0.1Hz ≤ f ≤ 10Hz Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: These are high power conditions and are therefore guaranteed only at temperatures equal to or below 70°C. Input is either floating, tied to output or held higher than output. Note 3: Output voltage drift is measured using the box method. Output voltage is recorded at TMIN, 25°C and TMAX. The lowest of these three readings is subtracted from the highest and the resultant difference is divided by (TMAX – TMIN). Note 4: Line regulation and load regulation are measured on a pulse basis with low duty cycle. Effects due to die heating must be taken into account separately. See thermal regulation and application section. Note 5: Load regulation is measured at a point 1/8" below the base of the package with Kelvin contacts. Note 6: Shunt regulation is measured with the input floating. This parameter is also guaranteed with the input connected (VIN – VOUT) > 1V, 0mA ≤ ISINK ≤ 10mA. Shunt and sink current flow into the output. Note 7: 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. Note 8: Minimum shunt current is measured with shunt voltage held 20mV below the value measured at 1mA shunt current. Note 9: Minimum input/output voltage is measured by holding input voltage 0.5V above the nominal output voltage, while measuring VIN – VOUT. Note 10: RMS noise is measured with a single pole highpass filter at 10Hz and a 2-pole lowpass filter at 1kHz. The resulting output is full-wave rectified 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 the nonideal bandpass of the filters. Note 11: If the part is stored outside of the specified temperature range, the output may shift due to hysteresis. 1019fd 4 LT1019 TYPICAL PERFOR A CE CHARACTERISTICS Quiescent Current (LT1019-2.5) 1.6 1.4 1.2 1.6 1.4 1.2 CURRENT (mA) CURRENT (mA) 1.0 0.8 0.6 0.4 0.2 0 0 5 10 125°C 25°C –55°C 1.0 0.8 0.6 0.4 0.2 0 125°C 25°C –55°C CURRENT (mA) 25 30 35 INPUT VOLTAGE (V) 15 20 Minimum Input/Output Voltage Differential 10 INPUT VOLTAGE/OUTPUT VOLTAGE (dB) OUTPUT CURRENT (mA) OUTPUT CHANGE (mV) 7.5 5.0 TJ = 125°C 2.5 TJ = – 55°C TJ = 25°C 0 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 INPUT/OUTPUT VOLTAGE (V) LT1019 • TPC04 Shunt Mode Characteristics (LT1019-2.5) 1.0 0.9 0.8 0.7 INPUT OPEN CURRENT (mA) CURRENT (mA) 0.6 0.5 0.4 0.3 0.2 0.1 0 0 TJ = 125°C TJ = 25°C TJ = – 55°C 0.5 1.0 1.5 2.0 2.5 3.0 3.5 OUTPUT-TO-GROUND VOLTAGE (V) 4.0 0.6 0.5 0.4 0.3 0.2 0.1 0 0 7 6 4 1 3 2 5 OUTPUT-TO-GROUND VOLTAGE (V) 8 TJ = 125°C TJ = 25°C TJ = – 55°C CURRENT (mA) UW 40 LT1019 • TPC01 LT1019 • TPC07 Quiescent Current (LT1019-4.5/LT1019-5) 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0 5 10 25 30 35 INPUT VOLTAGE (V) 15 20 40 45 0 Quiescent Current (LT1019-10) 125°C 25°C –55°C 45 0 5 10 15 20 25 30 35 INPUT VOLTAGE (V) 40 45 LT1019 • TPC02 LT1019 • TPC03 Load Regulation 2.0 TJ = 25°C 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –2.0 –10 –8 –6 –4 –2 0 2 4 6 8 SINKING SOURCING OUTPUT CURENT (mA) 10 LT1019-2.5 LT1019-10 LT1019-4.5/LT1019-5 Ripple Rejection 120 TJ = 25°C 110 100 90 80 70 60 50 40 10 100 1k 10k FREQUENCY (Hz) 100k 1M LT1019-2.5 LT1019-10 LT1019-4.5 LT1019-5 LT1019 • TPC05 LT1019 • TPC06 Shunt Mode Characteristics (LT1019-5) 1.0 0.9 0.8 0.7 INPUT OPEN 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 Shunt Mode Characteristics (LT1019-10) INPUT OPEN TJ = 125°C TJ = 25°C TJ = – 55°C 0 8 2 6 4 10 12 14 OUTPUT-TO-GROUND VOLTAGE (V) 16 LT1019 • TPC08 LT1019 • TPC09 1019fd 5 LT1019 TYPICAL PERFOR A CE CHARACTERISTICS Temp Pin Voltage 0.90 0.85 OUTPUT VOLTAGE CHANGE (µV) 140 120 100 80 60 40 20 0 –10 –20 –30 LT1019-2.5 LT1019-5 LT1019-10 OUTPUT CAPACITOR (µF) IOUT TJ = 25°C 0.80 0.75 VOLTAGE (V) 0.70 0.65 0.60 0.55 0.50 0.45 0.40 50 25 0 75 100 –50 –25 JUNCTION TEMPERATURE (°C) 125 BLOCK DIAGRA TRIM R2 LT1019-4.5, LT1019-5, LT1019-10 = 5k LT1019-2.5 = 10k 1.188V APPLICATIO S I FOR ATIO Line and Load Regulation Line regulation on the LT1019 is nearly perfect. A 10V change in input voltage causes a typical output shift of less than 5ppm. Load regulation (sourcing current) is nearly as good. A 5mA change in load current shifts output voltage by only 100µV. These are electrical effects, measured with low duty cycle pulses to eliminate heating effects. In real world applications, the thermal effects of load and line changes must be considered. Two separate thermal effects are evident in monolithic circuits. One is a gradient effect, where power dissipation on the die creates temperature gradients. These gradients can cause output voltage shifts even if the overall temperature coefficient of the reference is zero. The LT1019, unlike previous references, specifies thermal regulation caused by die temperature gradients.The specification is 0.5ppm/mW. To calculate the effect on output voltage, simply multiply the change in device power dissipation by 1019fd 6 + – U W UW LT1019 • TPC10 Line Regulation 10 LT1019-2.5* Stability with Output Capacitance 1 REGION OF POSSIBLE INSTABILITY 0.1 0.01 0.001 0 5 10 15 20 25 30 INPUT VOLTAGE (V) 35 40 0.0001 20 LT1019 • TPC11 0 10 15 20 15 10 5 5 SINK CURRENT SOURCE CURRENT OUTPUT CURRENT (mA) 1019 G12 *LT1019-4.5/LT1019-5/LT1019-10 ARE STABLE WITH ALL LOAD CAPACITANCE. W R1 LT1019-2.5 = 11k LT1019-4.5 = 13.9k LT1019-5 = 16k LT1019-10 = 37.1k R3 80k VIN VOUT GND LT1019 • BD U U LT1019 APPLICATIO S I FOR ATIO the thermal regulation specification. Example: a 10V device with a nominal input voltage of 15V and load current of 5mA. Find the effect of an input voltage change of 1V and a load current change of 2mA. ∆P (line change) = (∆VIN)(ILOAD) = (1V)(5mA) = 5mW ∆VOUT = (0.5ppm/mW)(5mW) = 2.5ppm ∆P (load change) = (∆ILOAD)(VIN – VOUT) = (2mA)(5V) = 10mW ∆VOUT = (0.5ppm/mW)(10mW) = 5ppm Even though these effects are small, they should be taken into account in critical applications, especially where input voltage or load current is high. The second thermal effect is overall die temperature change. The magnitude of this change is the product of change in power dissipation times the thermal resistance (θJA) of the IC package ≅ (100°C/W to 150°C/W). The effect on the reference output is calculated by multiplying die temperature change by the temperature drift specification of the reference. Example: same conditions as above with θJA = 150°C/W and an LT1019 with 20ppm/°C drift specification. ∆P (line change) = 5mW ∆VOUT = (5mW)(150°C/W)(20ppm/°C) = 15ppm ∆P (load change) = 10mW ∆VOUT = (10mW)(150°C/W)(20ppm/°C) = 30ppm These calculations show that thermally induced output voltage variations can easily exceed the electrical effects. In critical applications where shifts in power dissipation are expected, a small clip-on heat sink can significantly improve these effects by reducing overall die temperature change. Alternately, an LT1019A can be used with four times lower TC. If warm-up drift is of concern, these measures will also help. With warm-up drift, total device power dissipation must be considered. In the example given, warm-up drift (worst case) is equal to: U Warm-up drift = [(VIN)(IQ) + (VIN – VOUT)(ILOAD)] [(θJA)(TC)] with IQ (quiescent current) = 0.6mA, Warm-up drift = [(15V)(0.6mA) + (5V)(5mA)] [(150°C/W)(25ppm/°C)] = 127.5ppm Note that 74% of the warm-up drift is due to load current times input/output differential. This emphasizes the importance of keeping both these numbers low in critical applications. Note that line regulation is now affected by reference output impedance. R1 should have a wattage rating high enough to withstand full input voltage if output shorts must be tolerated. Even with load currents below 10mA, R1 can be used to reduce power dissipation in the LT1019 for lower warm-up drift, etc. Output Trimming Output voltage trimming on the LT1019 is nominally accomplished with a potentiometer connected from output to ground with the wiper tied to the trim pin. The LT1019 was made compatible with existing references, so the trim range is large: + 6%, – 6% for the LT1019-2.5, + 5%, – 13% for the LT1019-5, and + 5%, – 27% for the LT1019-10. This large trim range makes precision trimming rather difficult. One solution is to insert resistors in series with both ends of the potentiometer. This has the disadvantage of potentially poor tracking between the fixed resistors and the potentiometer. A second method of reducing trim range is to insert a resistor in series with the wiper of the potentiometer. This works well only for very small trim range because of the mismatch in TCs between the series resistor and the internal thin film resistors. These film resistors can have a TC as high as 500ppm/°C. That same TC is then transferred to the change in output voltage: a 1% shift in output voltage causes a (500ppm)(1%) = 5ppm/°C change in output voltage drift. 1019fd W UU 7 LT1019 APPLICATIO S I FOR ATIO The worst-case error in initial output voltage for the LT1019 is 0.2%, so a series resistor is satisfactory if the output is simply trimmed to nominal value. The maximum TC shift expected would be 1ppm/°C. Using the Temp Pin The LT1019 has a TEMP pin like several other bandgap references. The voltage on this pin is directly proportional to absolute temperature (PTAT) with a slope of approximately 2.1mV/°C. Room temperature voltage is therefore approximately (295°K)(2.1mV/°C) = 620mV. This voltage varies with process parameters and should not be used to measure absolute temperature, but rather relative temperature changes. Previous bandgap references have been very sensitive to any loading on the TEMP pin because it is an integral part of the reference “core” itself. The LT1019 “taps” the core at a special point which has much less effect on the reference. The relationship between TEMP pin loading and a change in reference output voltage is less than 0.05%/µA, about ten times improvement over previous references. Output Bypassing The LT1019 is designed to be stable with a wide range of load currents and output capacitors. The 4.5V, 5V, and 10V devices do not oscillate under any combination of TYPICAL APPLICATIO S Wide Range Trim ≥ ± 5% OUT VIN IN LT1019 TRIM GND R1 25k VOUT 1019 TA03 8 U capacitance and load. The 2.5V device can oscillate when sinking currents between 1mA and 6mA for load capacitance between 400pF and 2µF (see Figure 1). If output bypassing is desired to reduce high frequency output impedance, keep in mind that loop phase margin is significantly reduced for output capacitors between 500pF and 1µF if the capacitor has low ESR (Effective Series Resistance). This can make the output “ring” with tranVIN VIN 2Ω TO 5Ω LT1019 2Ω TO 5Ω LT1019 W U UU + + (a) 2µF TANTALUM (b) 2µF TO 10µF TANTALUM 1019 F01 Figure 1. Output Bypassing sient loads. The best transient load response is obtained by deliberately adding a resistor to increase ESR as shown in Figure 1. Use configuration (a) if DC voltage error cannot be compromised as load current changes. Use (b) if absolute minimum peak perturbation at the load is needed. For best transient response, the output can be loaded with ≥ 1mA DC current. Narrow Trim Range (± 0.2%) OUT VIN IN LT1019 TRIM GND R2* 1.5M VOUT R1 100k *INCREASE TO 4.7M FOR LT1019A (± 0.05%) 1019 TA05 1019fd LT1019 TYPICAL APPLICATIO S Trimming LT1019-5 Output to 5.120V VOUT OUT IN LT1019-5 TRIM GND 41.2k 1% 5k* ±1% TRIM 4.02k 1% VIN *LOW TC CERMET Precision 1µA Current Source 15V 11.5k 1% OUT IN 5k* 8.25k 1% LT1019-2.5 TRIM GND R2* –VIN 2.49M 1% LT1012 IOUT = 1µA ZOUT ≥ 1011Ω *LOW TC CERMET, TRIM RANGE = ± 1.5% V + ≥ (VOUT + 2.8V) LED GLOWS IN CURRENT LIMIT (DO NOT OMIT) R1 220Ω 8.2Ω 2N2905 IN LT1019 OUT GND U Trimming LT1019-10 Output to 10.240V VOUT OUT IN LT1019-10 TRIM GND 90.9k 1% 5k* ± 1% TRIM 4.02k 1% VIN *LOW TC CERMET 1019 TA04 1019 TA06 Negative Series Reference V+ R1* IN D1* LT1019 OUT GND VOUT ± 11V COMPLIANCE Q1 2N2905 –VREF AT 50mA + 1019 TA07 – + V – – VREF *R1 = V – 5V , R2 = , D1 = VREF + 5V 1mA 2mA 1019 TA10 Output Current Boost with Current Limit ILOAD ≤ 100mA 2µF SOLID TANTALUM 1019 TA08 1019fd 9 W W LT1019 SCHE ATIC DIAGRA VIN 10 R23 100Ω Q29 Q28 Q27 Q32 Q31 Q30 R24 850Ω Q25 R33 1k Q20 R20 750Ω Q33 R32 500Ω Q26 R21 20Ω VOUT R25 1k Q34 R15 3k Q4 Q5 Q6A Q6B Q18 Q19 Q21 C4 R35 27k Q16 R5 Q14 Q17 Q15 Q22 Q2 R16 Q35 3k Q23 Q24 R31 22k R19 15Ω R26 3k R28 9k R27 9k R34 4k R17 500Ω C3 R9 3k Q8 Q9 Q38 Q36 1k R39 R36 82k Q37 R42 4k R38 3.75k Q7 R11A 1.9k R12 7.2k Q10 R18 2k Q11 Q12 Q13 R37 2k R11B 1k R13 24.5k GND R1 Q3 SHORT FOR 2.5 R2 R14 72k R4 R29 TRIM 80k Q1 R6 780Ω R7 1.6k R8 2.5k R3 5k 1019fd LT1019 PACKAGE DESCRIPTIO U H Package 8-Lead TO-5 Metal Can (0.200 PCD) (LTC DWG # 05-08-1320) 0.335 – 0.370 (8.509 – 9.398) DIA 0.305 – 0.335 (7.747 – 8.509) 0.040 (1.016) MAX 0.050 (1.270) MAX GAUGE PLANE 0.010 – 0.045* (0.254 – 1.143) 0.016 – 0.021** (0.406 – 0.533) 0.165 – 0.185 (4.191 – 4.699) REFERENCE PLANE 0.500 – 0.750 (12.700 – 19.050) 0.110 – 0.160 (2.794 – 4.064) INSULATING STANDOFF *LEAD DIAMETER IS UNCONTROLLED BETWEEN THE REFERENCE PLANE AND 0.045" BELOW THE REFERENCE PLANE 0.016 – 0.024 **FOR SOLDER DIP LEAD FINISH, LEAD DIAMETER IS (0.406 – 0.610) 0.027 – 0.045 (0.686 – 1.143) 45°TYP 0.028 – 0.034 (0.711 – 0.864) PIN 1 0.200 (5.080) TYP SEATING PLANE OBSOLETE N8 Package 8-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.400* (10.160) MAX 8 7 6 5 H8(TO-5) 0.200 PCD 1197 0.300 – 0.325 (7.620 – 8.255) 0.045 – 0.065 (1.143 – 1.651) 0.130 ± 0.005 (3.302 ± 0.127) 0.009 – 0.015 (0.229 – 0.381) +0.035 0.325 –0.015 0.065 (1.651) TYP 0.125 (3.175) 0.020 MIN (0.508) MIN 0.018 ± 0.003 (0.457 ± 0.076) 0.255 ± 0.015* (6.477 ± 0.381) 1 2 3 4 ( +0.889 8.255 –0.381 ) 0.100 (2.54) BSC N8 1098 *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) S8 Package 8-Lead Plastic Small Outline (Narrow 0.150) (LTC DWG # 05-08-1610) .045 ±.005 .050 BSC .010 – .020 × 45° (0.254 – 0.508) .008 – .010 (0.203 – 0.254) .160 ±.005 .016 – .050 (0.406 – 1.270) NOTE: 1. DIMENSIONS IN .189 – .197 (4.801 – 5.004) NOTE 3 .053 – .069 (1.346 – 1.752) 0°– 8° TYP 8 .004 – .010 (0.101 – 0.254) .228 – .244 (5.791 – 6.197) .150 – .157 (3.810 – 3.988) NOTE 3 7 6 5 .245 MIN .030 ±.005 TYP RECOMMENDED SOLDER PAD LAYOUT 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) .014 – .019 (0.355 – 0.483) TYP .050 (1.270) BSC 1 SO8 0303 2 3 4 1019fd 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. 11 LT1019 TYPICAL APPLICATION Negative 10V Reference for CMOS DAC OUT LT1019-10 TRIM GND IOUT REF 1.2k –15V *LOW TC CERMET, TRIM RANGE = ±1.5% RELATED PARTS PART NUMBER LT1027 LT1236 LT1460 LT1634 LTC1798 LT1461 DESCRIPTION Precision 5V Reference Precision Reference Micropower Precision Series Reference Micropower Precision Shunt Reference Micropower Low Dropout Reference Micropower Low Dropout Reference COMMENTS Lowest TC, High Accuracy, Low Noise, Zener Based 5V and 10V Zener Based, 5ppm/°C, SO-8 Package Bandgap, 130µA Supply Current, 10ppm/°C, Available in SOT-23 Package Bandgap 0.05%, 10ppm/°C, 10µA Supply Current 0.15% Max, 6.5µA Supply Current 3ppm/°C, 0.04%, 50µA Supply Current 1019fd LT/TP 0205 1K REV D • PRINTED IN USA 12 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com + – U 59k 1% 5k* 5.76k 1% LTC1595 FB 30pF VOUT LT1007 1019 TA09 © LINEAR TECHNOLOGY CORPORATION 1993