LT6650 Micropower, 400mV Reference with Rail-to-Rail Buffer Amplifier in SOT-23 U DESCRIPTIO FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ Low Quiescent Current 5.6µA (typical) Wide Supply Range: 1.4V to 18V 400mV Reference ±1% Maximum Accuracy Over Temperature at 5V Rail-to-Rail Buffer Amplifier 0.5% 400mV Maximum Initial Accuracy at 5V Shunt Configurable Sinks and Sources Current Wide Operational Range –40°C to 125°C Externally Adjustable Output Voltage Low Profile 1mm 5-lead SOT-23 (ThinSOT™) Package U APPLICATIO S ■ ■ ■ ■ The reference is postpackage-trimmed to increase the output accuracy. The output can sink and source 200µA over temperature. Quiescent power dissipation is 28µW. Stability is ensured with any output capacitor of 1µF or higher. The LT6650 is the lowest voltage series reference available in the 5-lead SOT-23 package. , LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. Battery-Operated Systems Handheld Instruments Industrial Control Systems Data Acquisition Systems Negative Voltage References U ■ The LT®6650 is a micropower, low voltage 400mV reference. Operating with supplies from 1.4V up to 18V, the device draws only 5.6µA typical, making it ideal for low voltage systems as well as handheld instruments and industrial control systems. With only two resistors the internal buffer amplifier can scale the 400mV reference to any desired value up to the supply voltage. TYPICAL APPLICATIO Battery-Powered 0.4V Reference LT6650 Temperature Drift 402 VIN = 1.4V TO 18V LT6650 IN VR = 400mV REFERENCE + – GND 1µF OUT 5 VOUT 0.4V REFERENCE VOLTAGE (mV) IQ ≈ 6µA 4 TYPICAL LT6650 PART VIN = 5V NO LOAD 401 SINK 200µA 400 SOURCE –200µA 399 FB 1 2 1µF 6650 TA01a 398 –50 –30 –10 10 30 50 70 90 110 130 TEMPERATURE (°C) 6650 TA01b 6650f 1 LT6650 U W W W ABSOLUTE AXI U RATI GS U W U PACKAGE/ORDER I FOR ATIO (Note 1) Total Supply Voltage (VIN to GND)........................... 20V FB Voltage (Note 2) ....................... 20V to (GND – 0.3V) Output Voltage (OUT) .................... 20V to (GND – 0.3V) Output Short Circuit Duration .......................... Indefinite FB Input Current ................................................... 10mA Operating Temperature Range ............... –40°C to 125°C Specified Temperature Range LT6650CS5 ............................................. 0°C to 70°C LT6650IS5 ........................................... –40°C to 85°C LT6650HS5 (Note 3) ......................... –40°C to 125°C Maximum Junction Temperature .......................... 150°C Storage Temperature Range (Note 4) ............................................. –65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C ORDER PART NUMBER LT6650CS5 LT6650IS5 LT6650HS5 TOP VIEW FB 1 5 OUT GND 2 DNC* 3 4 IN S5 PART MARKING S5 PACKAGE 5-LEAD PLASTIC TSOT-23 TJMAX = 150°C, θJA = 230°C/W LBDV *Do Not Connect The temperature grades are identified by a label on the shipping container. Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 5V, CIN = 1µF, FB = OUT, no DC load, CL = 1µF, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS VOUT Output Voltage (Notes 4, 5) LT6650 398 –0.5 400 402 0.5 mV % VIN Operating Input Voltage ∆VOUT/∆VIN Line Regulation LT6650CS5 ● ● 397 –0.75 400 403 0.75 mV % LT6650IS5 ● ● 396 –1 400 404 1 mV % LT6650HS5 ● ● 394 –1.5 400 406 1.5 mV % 1.4 Load Regulation (Note 6) mV ppm/V ● ● 7.5 1130 mV ppm/V LT6650HS5 ● ● 8.5 1280 mV ppm/V –0.04 500 –0.2 2500 –0.4 5000 mV ppm/mA mV ppm/mA 0.24 3000 1 12500 2 20000 mV ppm/mA mV ppm/mA Sourcing from 0µA to –200µA Sinking from 0µA to 200µA ● ● Output Voltage Temperature Coefficient (Note 10) 6 900 LT6650CS5, LT6650IS5 ● ● TC V 1.4V ≤ VIN ≤ 18V 1 150 ∆VOUT/∆IOUT 18 ● 30 ppm/°C 6650f 2 LT6650 ELECTRICAL CHARACTERISTICS The ● denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 5V, CIN = 1µF, FB = OUT, no DC load, CL = 1µF, unless otherwise noted. SYMBOL PARAMETER ∆VDO Dropout Voltage (Note 7) CONDITIONS MIN Referred to VIN = 1.8V, VOUT = 1.4V (RF = 100k, RG = 39.2k) ∆VOUT = –0.1%, IOUT = 0µA TYP MAX UNITS 75 100 150 mV mV 165 250 350 mV mV –300 –150 0 mV mV ● ∆VOUT = –0.1%, IOUT = –200µA Sourcing ● ∆VOUT = –0.1%, IOUT = 200µA Sinking (Note 11) ● ISC Short-Circuit Output Current IIN Supply Current VOUT Shorted to GND VOUT Shorted to VIN 5 9 5.6 11 14 µA µA 5.9 12 15 µA µA 1.2 10 15 30 nA nA nA ● VIN = 18V ● IFB FB Pin Input Current mA mA VFB = VOUT = 400mV LT6650CS5, LT6650IS5 LT6650HS5 ● ● TON Turn-On Time CLOAD = 1µF 0.5 ms en Output Noise (Note 8) 0.1Hz ≤ ƒ ≤ 10Hz 10Hz ≤ ƒ ≤ 1KHz, IOUT = –200µA Sourcing 20 23 µVP-P µVRMS VHYS Hysteresis (Note 9) ∆T = 0°C to 70°C ∆T = –40°C to 85°C Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: The FB pin is protected by an ESD diode to the ground. If the FB input voltage exceeds –0.3V below ground, the FB input current should be limited to less than 10mA. If the FB input voltage is greater than 5V, the FB input current is expected to meet specified performance from Typical Performance Characteristics but is not tested or QA sampled at this voltage. Note 3: If the part is operating at temperatures above 85°C, it is recommended to enhance the stability margin by using an output capacitor greater than 10µF or a series RC combination having a 100µs equivalent time constant. See Application section for details. Note 4: If the part is stored outside of the specified temperature range, the output voltage may shift due to hysteresis. Note 5: ESD (Electrostatic Discharge) sensitive devices. Extensive use of ESD protection devices are used internal to the LT6650; however, high electrostatic discharge can damage or degrade the device. Use proper ESD handling precautions. ● ● ● ● 0.1 250 0.24 600 mV ppm mV ppm Note 6: 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 7: Dropout Voltage is (VIN – VOUT) when VOUT falls to 0.1% below its nominal value at VIN = 1.8V. Note 8: Peak-to-Peak noise is measured with a single pole highpass filter at 0.1Hz and a 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 seconds. Note 9: Hysteresis in the 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 a successive measurement. Hysteresis is roughly proportional to the square of the temperature change. Note 10: Temperature coefficient is measured by dividing the change in output voltage by the specified temperature range. Note 11: This feature guarantees the shunt mode operation of the device. 6650f 3 LT6650 U W TYPICAL PERFOR A CE CHARACTERISTICS Output Voltage Temperature Drift 404 (See Applications, Figure 1) Output Voltage Temperature Drift 403 TYPICAL PART Supply Current vs Input Voltage 10 THREE PARTS VIN = 5V 403 8 OUTPUT VOLTAGE (mV) OUTPUT VOLTAGE (mV) 401 VIN = 1.4V 400 399 VIN = 18V 398 VIN = 5V SUPPLY CURRENT (µA) 402 402 401 400 125°C 6 25°C 4 –55°C 399 2 398 –60 –40 –20 0 20 40 60 80 100 120 TEMPERATURE (°C) 0 397 396 –60 –40 –20 0 20 40 60 80 100 120 TEMPERATURE (°C) 6650 G01 Supply Current vs Input Voltage –55°C 2 0 404 403 403 402 TA = 125°C 401 TA = –55°C 400 TA = 25°C 399 398 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 INPUT VOLTAGE (V) 2 4 6 10 12 14 8 INPUT VOLTAGE (V) 16 Load Regulation (Sourcing) 1000 –30 –55°C –40 400 TA = 25°C –50 –60 –70 –80 –90 TA = 125°C 398 0.8 18 1.0 1.4 1.2 1.6 INPUT VOLTAGE (V) 700 –55°C 25°C 500 400 2.0 Minimum Input-Output Voltage Differential (Sourcing) 800 600 1.8 6650 G06 500 TYPICAL PART VIN = 5V 900 OUTPUT VOLTAGE CHANGE (µV) OUTPUT VOLTAGE CHANGE (µV) 25°C 125°C –20 TA = –55°C Load Regulation (Sinking) TYPICAL PART VIN = 5V –10 401 6550 G05 6650 G04 0 402 399 INPUT-OUTPUT VOLTAGE (mV) 4 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) Line Regulation 404 OUTPUT VOLTAGE (mV) OUTPUT VOLTAGE (mV) SUPPLY CURRENT (µA) 25°C 4 6650 G03 Line Regulation 125°C 6 2 6650 G02 10 8 0 125°C 300 200 VOUT = 1.425V - TYP (RF = 100k, RG = 39.2k) 0.1% VOUT 400 125°C 300 25°C 200 –55°C 100 100 –100 0 10 100 OUTPUT CURRENT (µA) 1000 6650 G07 0 10 100 OUTPUT CURRENT (µA) 1000 6650 G08 10 100 OUTPUT CURRENT (µA) 1000 6650 G09 6650f 4 LT6650 U W TYPICAL PERFOR A CE CHARACTERISTICS Minimum Input-Output Voltage Differential (Sinking) Output Short Circuit Current vs Input Voltage 14 VOUT = 1.425V - TYP (RF = 100k, RG = 39.2k) 0.1% VOUT Output Short Circuit Current vs Input Voltage 14 OUTPUT SHORTED TO GND –55°C –200 25°C –300 10 125°C 8 25°C 6 –400 OUTPUT SHORTED TO VIN 12 OUTPUT CURRENT (mA) 12 –100 OUTPUT CURRENT (mA) INPUT-OUTPUT VOLTAGE (mV) 0 (See Applications, Figure 1) 4 25°C 125°C 10 –55°C 8 6 4 –55°C 125°C –500 100 OUTPUT CURRENT(µA) 2 1000 0 2 4 6650 G10 FB Pin Current vs FB Pin Voltage –4 VFB ≠ VOUT CURRENT IS POSITIVE WHEN IT ENTERS THE DEVICE 125°C 1 0.1 25°C –8 25°C –10 –0.6 –0.4 –0.2 0 0.2 0.4 0.6 FB PIN VOLTAGE (V) 0.8 1.0 –55°C 0.01 1 3 5 7 9 11 13 15 FB PIN VOLTAGE (V) 17 120 120 100 100 80 80 60 GAIN 19 40 20 20 Output Noise 0.1Hz to 10Hz –20 1 10 FREQUENCY (kHz) VIN = 5V NOISE LEVEL (µV/√Hz) Integrated Noise 10Hz to 1kHz 100 VIN = 5V CL = 1µF 15 10 IOUT = 0µA –40 100 6650 G15 Output Voltage Noise Spectrum 20 OUTPUT NOISE (5µV/DIV) 0 6650 G14 6650 G13 60 PHASE 40 0 T = 25°C A UNITY GAIN –20 R = 2k L CL = 1µF –40 0.1 0.01 –55°C –6 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) Gain and Phase vs Frequency GAIN (dB) FB PIN CURRENT (nA) 0 –2 4 PHASE (DEG) FB PIN CURRENT (nA) VFB ≠ VOUT 8 CURRENT IS POSITIVE WHEN IT ENTERS THE DEVICE 6 125°C 2 6650 G12 FB Pin Current vs FB Pin Voltage 10 4 0 6650 G11 10 2 2 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) IOUT = –200µA 5 INTEGRATED NOISE (µVRMS) 10 VIN = 5V CL = 1µF IOUT = –200µA 10 IOUT = –40µA 0 0 1 2 3 4 5 6 TIME (s) 7 8 9 10 6650 G16 10 100 1k FREQUENCY (Hz) 10k 6650 G17 1 10 100 FREQUENCY (Hz) 1k 6650 G18 6650f 5 LT6650 U W TYPICAL PERFOR A CE CHARACTERISTICS IOUT = 0µA RZ = 0Ω CL = 10µF 100 OUTPUT IMPEDANCE (Ω) CL = 1µF 10 CL = 47µF 1 IOUT = –40µA RZ = 0Ω 100 CL = 10µF CL = 1µF CL = 47µF 10 1 100 1k 10k FREQUENCY (Hz) 100k 100 1k 10k FREQUENCY (Hz) 6650 G19 POWER SUPPLY REJECTION RATIO (dB) POWER SUPPLY REJECTION RATIO (dB) CL = 10µF CL = 1µF –20 –30 –40 –50 CL = 47µF –60 –70 –80 100 1k 10k FREQUENCY (Hz) IOUT = –40µA 10 RZ = 0Ω 0 CL = 10µF CL = 1µF –10 CL = 47µF –20 –30 –40 –50 –60 –70 100k Power Supply Rejection Ratio vs Frequency –60 CL = 47µF –70 –80 100 1k 10k FREQUENCY (Hz) 100 1k 10k FREQUENCY (Hz) 100k 6650 G25 0 –10 CL = 1µF –20 –30 CL = 10µF –40 –50 CL = 47µF –60 –70 100k 10 100 1k 10k FREQUENCY (Hz) –20 CL = 10µF –30 –40 CL = 1µF –50 100k 6650 G24 Power Supply Rejection Ratio vs Frequency 20 IOUT = –40µA 10 RZ = 0Ω C = 1µF 0 RIN = 1k IN –10 CL = 47µF –60 –70 –80 10 IOUT = 0µA 10 CL • RZ = 100µs Power Supply Rejection Ratio vs Frequency POWER SUPPLY REJECTION RATIO (dB) –50 100k 6650 G21 20 –40 1k 10k FREQUENCY (Hz) 6650 G23 20 –30 100 –80 10 Power Supply Rejection Ratio vs Frequency CL = 1µF CL = 47µF 20 6650 G22 IOUT = 0µA 10 RZ = 0Ω C = 1µF 0 RIN = 1k IN –10 CL = 10µF –20 10 10 –80 10 CL = 10µF 100k 20 0 100 Power Supply Rejection Ratio vs Frequency 20 –10 CL = 1µF 6650 G20 Power Supply Rejection Ratio vs Frequency IOUT = 0µA 10 RZ = 0Ω IOUT = 0µA CL • RZ = 100µs 1 10 POWER SUPPLY REJECTION RATIO (dB) 10 POWER SUPPLY REJECTION RATIO (dB) Output Impedance vs Frequency 1000 POWER SUPPLY REJECTION RATIO (dB) OUTPUT IMPEDANCE (Ω) Output Impedance vs Frequency 1000 OUTPUT IMPEDANCE (Ω) Output Impedance vs Frequency 1000 (See Applications, Figure 1) IOUT = 0µA 10 CL • RZ = 100µs C = 1µF 0 RIN = 1k IN –10 –20 CL = 10µF –30 CL = 1µF –40 –50 CL = 47µF –60 –70 –80 10 100 1k 10k FREQUENCY (Hz) 100k 6650 G26 10 100 1k 10k FREQUENCY (Hz) 100k 6650 G27 6650f 6 LT6650 U U U PI FU CTIO S FB (Pin 1): Resistor Divider Feedback Pin. Connect a resistor divider from OUT to GND and the center tap to FB. This pin sets the output potential. GND (Pin 2): Ground Connection. DNC (Pin 3): Do not connect. Connected internally for post package trim. This pin must be left unconnected. IN (Pin 4): Positive Supply. Bypassing with a 1µF capacitor is recommended if the output loading changes. OUT (Pin 5): Reference Output. The output sources and sinks current. It is stable with any load capacitor with a total capacitance of 1µF or more. Higher load capacitance improves load transient response. W BLOCK DIAGRA IN 4 VR = 400mV REFERENCE LT6650 + 5 OUT – DNC 3 1 FB 2 6650 BD GND U W U U APPLICATIO S I FOR ATIO Long Battery Life The LT6650 is a micropower, adjustable reference which operates from supply voltages ranging from 1.4V to 18V. The series regulated output may be configured with external resistors to any voltage from 400mV to nearly the supply potential. Under no-load conditions, the LT6650 dissipates only 8µW when operating on a 1.4V supply. Other operating configurations allow the LT6650 to be used as a micropower positive or negative adjustable shunt reference from 1.4V to 18V. Bypass and Load Capacitor The LT6650 voltage reference requires a 1µF or greater output capacitance for proper operation. This capacitance may be provided by either a single capacitor connected between OUT and GND or formed by the aggregate of several capacitors that may be serving other decoupling functions. Output impedance can be reduced by DC loading of the output by 40µA to 200µA, and/or adding an RZ to the output capacitor for a 100µs time constant as shown in Figure 1 and the Typical Performance Characteristics graphs. The LT6650 Voltage reference should have an input bypass capacitor of 0.1µF or larger. When the circuit is RIN VIN IN CIN 4 5 OUT CL LT6650 1 2 VOUT FB RZ 6650 F01 GND Figure 1. LT6650 Input-Output Configuration 6650f 7 LT6650 U U W U APPLICATIO S I FOR ATIO operated from a small battery or other relatively high impedance source, a minimum 1µF capacitor is recommended. PSRR can be significantly enhanced by adding a low-pass RC filter on the input, with a time-constant of 1ms or higher, as shown in Figure 1. The Typical Performance Characteristics graphs show performance as a function of several combinations of input and output capacitance. the same circuit responding to input transients of 0.5V, settling in about 0.3ms. Figures 5 through 7 show the same circuit responding to various load steps: changes between ±100µA in Figure 5; sourcing current step between –100µA and –200µA in Figure 6; and sinking current VIN 3V 2.5V An input RC of 100ms or more is recommended (such as 5k and 22µF) when output transients must be minimized in the face of high supply noise, such as in automotive applications. Figure 2 shows an input filter structure that effectively eliminates supply transients from affecting the output. With this extra input decoupling and the LT6650 operating normally from a 12V bus, 50V transients induce less than <0.5% VOUT perturbations. VOUT 0.4V 0V Figure 3 shows the turn-on response time for the circuit in Figure 1. The input voltage steps from 0V to 3V, and the output is configured to produce 400mV. Input bypass and output load capacitance are 1µF, RIN = 0Ω, RZ = 0Ω, and the output settles in approximately 0.5ms. Figure 4 shows VOUT 10mV/DIV SINKING 6650 F04 Figure 4. Output Response to ±0.5V Input Step SOURCING IOUT 100µA SINKING NOISY POWER BUS 33k 2ms/DIV 100µA SOURCING 4.7k VIN 1µF 6650 F05 1N751 5V 22µF Figure 5. Output Response to Bidirectional Load Step (100µA to –100µA) 6650 F02 Figure 2. High Noise-Immunity Input Network VOUT 10mV/DIV AC VIN 3V IOUT –100µA VOUT –200µA 0.4V 0V 0V 6650 F06 0.2ms/DIV 6650 F03 Figure 3. LT6650 Turn-On Characteristic Figure 6. Output Response to Current-Sourcing Load Step (–100µA to –200µA) 6650f 8 LT6650 U U W U APPLICATIO S I FOR ATIO step between 100µA and 200µA in Figure 7. Load step settling occurs in about 0.5ms or less (to ±0.2%). Output Adjustment If the LT6650 is to be used as a 400mV reference, then the output and feedback pins may be tied together without any scale-setting components as shown in the front-page application circuit. Setting the output to any higher voltage is a simple matter of selecting two feedback resistors to configure the non-inverting gain of the internal operational amplifier, as shown in Figure 8. A feedback resistor RF is connected between the OUT pin and the FB pin, and a gain resistor RG is connected from the FB pin to GND. The resistor values are related to the output voltage by the following relationship: RF = RG • (VOUT – 0.4)/(0.4 – IFB • RG) The IFB term represents the FB pin bias current, and can generally be neglected when RG is 100k or less. For RG␣ ≤␣ 20k, even worst-case IFB can be neglected (error contribution <0.15%). Since the VOUT error distribution increases at twice the resistor tolerance, high accuracy resistors or resistor networks are recommended. The output voltage may be set to any level from 400mV up to 350mV below the supply voltage with source or sink capability. Noise Reduction Capacitor In applications involving the use of resistive feedback for reference scaling, the intrinsic reference noise is amplified along with the DC level. To minimize noise amplification, the use of a 1nF feedback capacitor is recommended, as shown in Figure 8 and other circuits with scaling resistors. Shunt Reference Operation The circuits shown in Figure 9 and Figure 10 form adjustable shunt references. Along with the external bias resistor RB, the LT6650 provides positive or negative reference operation for outputs between 1.4V and 18V (positive or negative). Just like a Zener diode, a supply VS is required, somewhat higher in magnitude than the desired reference VS VOUT 10mV/DIV AC RB VOUT = 0.4V • (1 + RF/RG) 4 IN OUT IOUT LT6650 200µA FB RF 1 10µF GND RG 2 100µA VOUT 1nF 5 6650 F09 6650 F07 Figure 7. Output Response to Current-Sinking Load Step (100µA to 200µA) 4 VOUT = 0.4V • (1 + RF/RG) 1k VS 4 1µF OUT LT6650 GND FB VOUT 1nF 5 IN Figure 9. Typical Configuration of LT6650 as Adjustable Positive Shunt Reference OUT LT6650 RF GND 1 1µF 1nF 5 IN 2 FB RF 1 10µF RG VOUT RG 2 RB VOUT = –0.4V • (1 + RF/RG) 6650 F08 –VS Figure 8. Typical Configuration for Output Voltages Greater than 0.4V 6650 F10 Figure 10. Typical Configuration of LT6650 as Adjustable Negative Shunt Reference 6650f 9 LT6650 U W U U APPLICATIO S I FOR ATIO VOUT. RB must be within the following range for proper operation (the optimal value depends greatly on the direction and magnitude of the load current): RB > |VS – VOUT|/(200µA + 0.4/RG) RB < |VS – VOUT|/(15µA + 0.4/RG) Limits of Operation Hysteresis Due to various mechanical stress mechanisms inherent to integrated-circuit packaging, internal offsets may not precisely recover from variations that occur over temperature, and this effect is referred to as hysteresis. Proprietary manufacturing steps minimize this hysteresis, though some small residual error can occur. Hysteresis measurements for the LT6650 can be seen in Figures 11 and 12. Figure 11 presents the worst-case data taken on parts subjected to thermal cycling between 0°C to 70°C, while Figure 12 shows data for –40°C to 85°C cycling. Units were cycled several times over these temperature ranges and the largest changes are shown. As would be expected, 6 the parts cycled over the higher temperature extremes exhibit a broader hysteresis distribution. The worst hysteresis measurements indicate voltage shifts of less than 1000ppm (0.1%) from their initial value. The LT6650 is a robust bipolar technology part. ESD clamp diodes are integrated into the design and are depicted in the Simplified Schematic for reference. Diodes are included between the GND pin and the IN, OUT, and FB pins to prevent reverse voltage stress on the device. Unusual modes of operation that forward-bias any these diodes should limit current to 10mA to avoid permanent damage to the device. The LT6650 is fabricated using a relatively high-voltage process, allowing any pin to independently operate at up to 20V with respect to GND. The part does not include any over voltage protection mechanisms; therefore caution should be exercised to avoid inadvertent application of higher voltages in circuits involving high potentials. 7 LIGHT COLUMNS 0°C TO 25°C DARK COLUMNS 70°C TO 25°C 6 NUMBER OF UNITS NUMBER OF UNITS 5 4 3 2 1 0 –400 LIGHT COLUMNS –40°C TO 25°C DARK COLUMNS 85°C TO 25°C 5 4 3 2 1 –200 200 400 0 DISTRIBUTION (ppm) 600 6650 F11 Figure 11. Worst-Case 0°C to 70°C Hysteresis 0 –1000 –750 –500 –250 0 250 500 750 1000 DISTRIBUTION (ppm) 6650 F12 Figure 12. Worst-Case –40°C to 85°C Hysteresis 6650f 10 LT6650 W W SI PLIFIED SCHE ATIC 5 IN IN IN 4 OUT IN 2 GND 1 FB 6650 SS U PACKAGE DESCRIPTIO S5 Package 5-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1635) 0.62 MAX 0.95 REF 2.90 BSC (NOTE 4) 1.22 REF 1.4 MIN 3.85 MAX 2.62 REF 2.80 BSC 1.50 – 1.75 (NOTE 4) PIN ONE RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.30 – 0.45 TYP 5 PLCS (NOTE 3) 0.95 BSC 0.80 – 0.90 0.20 BSC 0.01 – 0.10 1.00 MAX DATUM ‘A’ 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 1.90 BSC S5 TSOT-23 0302 6650f 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 LT6650 U TYPICAL APPLICATIO Adjustable Micropower “Zener” 2-Terminal Reference CATHODE 4 IN OUT LT6650 FB CATHODE 1nF 5 RF 1 10µF GND = 1.4V ≤ VZ ≤ 18V 30µA ≤ IZ ≤ 220µA VZ = 0.4V • (1 + RF/RG) RG 2 ANODE ANODE 6650 TA02 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1790 Micropower LDO Precision Reference 0.05% Max Sources/Sinks-Current Available in SOT-23 LT1460 Micropower Precision Reference 0.075% Max 10ppm/ºC Available in SOT-23 LT1461 Micropower LDO Low TC Precision Reference 0.04% Max 3ppm/ºC 35µA Supply Current LT1494/LT1495/ LT1496 Single/Dual/Quad Micropower Op Amps 1.5µA, VOS < 375µV, IB < 1000pA LTC1540 Nanopower Comparator with Reference 300nA, Available in 3mm × 3mm DFN Package LTC1798 Micropower LDO Reference 0.15% Max 6.5µA Supply Current LT6700 Micropower Dual Comparator with Reference 6.5µA, Choice of Polarities Available in SOT-23 6650f 12 Linear Technology Corporation LT/TP 0504 1K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com LINEAR TECHNOLOGY CORPORATION 2003