LT3014B 20mA, 3V to 80V Low Dropout Micropower Linear Regulator FEATURES DESCRIPTION Wide Input Voltage Range: 3V to 80V Low Quiescent Current: 7µA Low Dropout Voltage: 350mV Output Current: 20mA LT3014BHV Survives 100V Transients (2ms) No Protection Diodes Needed Adjustable Output from 1.22V to 60V Stable with 0.47µF Output Capacitor Stable with Aluminum, Tantalum or Ceramic Capacitors n Reverse-Battery Protection n No Reverse Current Flow from Output n Thermal Limiting n Available in 5-Lead ThinSOTTM and 8-Lead DFN Packages The LT®3014B is a high voltage, micropower low dropoutlinear regulator. The device is capable of supplying 20mA of output current with a dropout voltage of 350mV. Designed for use in battery-powered or high voltage systems, the low quiescent current (7µA operating) makes the LT3014B an ideal choice. Quiescent current is also well controlled in dropout. n n n n n n n n n The device is available as an adjustable device with a 1.22V reference voltage. The LT3014B regulator is available in the 5-lead ThinSOT and 8-lead DFN packages. APPLICATIONS n n n n Other features of the LT3014B include the ability to operate with very small output capacitors. The regulators are stable with only 0.47µF on the output while most older devices require between 10µF and 100µF for stability. Small ceramic capacitors can be used without the necessary addition of ESR as is common with other regulators. Internal protection circuitry includes reverse-battery protection, current limiting, thermal limiting and reverse current protection. Low Current High Voltage Regulators Regulator for Battery-Powered Systems Telecom Applications Automotive Applications L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6118263, 6144250. TYPICAL APPLICATION Dropout Voltage 5V Supply VIN 5.4V TO 80V 1µF OUT LT3014B 3.92M ADJ GND 1.27M 3014B TA01 VOUT 5V 20mA 0.47µF 350 DROPOUT VOLTAGE (mV) IN 400 300 250 200 150 100 50 0 0 2 4 6 8 10 12 14 16 18 20 OUTPUT CURRENT (mA) 3014B TA02 3014bfb For more information www.linear.com/LT3014B 1 LT3014B ABSOLUTE MAXIMUM RATINGS (Note 1) IN Pin Voltage, Operating.........................................±80V Transient (2ms Survival, LT3014BHV)................... +100V OUT Pin Voltage.......................................................±60V IN to OUT Differential Voltage................................. ±80V ADJ Pin Voltage.........................................................±7V Output Short-Circuit Duration........................... Indefinite Storage Temperature Range ThinSOT Package............................–65°C to 150°C DFN Package...................................–65°C to 125°C Operating Junction Temperature Range (Notes 3, 9, 10) E-Grade, I-Grade.............................–40°C to 125°C MP-Grade........................................–55°C to 125°C Lead Temperature (Soldering, 10 sec) SOT-23 Package.............................................300°C PIN CONFIGURATION TOP VIEW TOP VIEW IN 1 5 OUT GND 2 NC 3 4 ADJ S5 PACKAGE 5-LEAD PLASTIC SOT-23 TJMAX = 125°C, θJA = 150°C/ W θJC = 25°C/W MEASURED AT PIN 2 SEE APPLICATIONS INFORMATION SECTION OUT 1 8 IN ADJ 2 7 NC NC 3 6 NC GND 4 5 NC 9 DD PACKAGE 8-LEAD (3mm × 3mm) PLASTIC DFN TJMAX = 125°C, θJA = 40°C/W θJC = 10°C/W MEASURED AT PIN 9 EXPOSED PAD (PIN 9) IS GND, MUST BE SOLDERED TO PCB 3014bfb 2 For more information www.linear.com/LT3014B LT3014B ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3014BES5#PBF LT3014BES5#TRPBF LTCHK 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BIS5#PBF LT3014BIS5#TRPBF LTCHK 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BMPS5#PBF LT3014BMPS5#TRPBF LTCHK 5-Lead Plastic SOT-23 –55°C to 125°C LT3014BHVES5#PBF LT3014BHVES5#TRPBF LTCHN 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BHVIS5#PBF LT3014BHVIS5#TRPBF LTCHN 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BEDD#PBF LT3014BEDD#TRPBF LCHM 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LT3014BIDD#PBF LT3014BIDD#TRPBF LCHM 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LT3014BHVEDD#PBF LT3014BHVEDD#TRPBF LCHP 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LT3014BHVIDD#PBF LT3014BHVIDD#TRPBF LCHP 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LEAD BASED FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LT3014BES5 LT3014BES5#TR LTCHK 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BIS5 LT3014BIS5#TR LTCHK 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BMPS5 LT3014BMPS5#TR LTCHK 5-Lead Plastic SOT-23 –55°C to 125°C LT3014BHVES5 LT3014BHVES5#TR LTCHN 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BHVIS5 LT3014BHVIS5#TR LTCHN 5-Lead Plastic SOT-23 –40°C to 125°C LT3014BEDD LT3014BEDD#TR LCHM 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LT3014BIDD LT3014BIDD#TR LCHM 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LT3014BHVEDD LT3014BHVEDD#TR LCHP 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C LT3014BHVIDD LT3014BHVIDD#TR LCHP 8-Lead (3mm × 3mm) Plastic DFN –40°C to 125°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ This product is only offered in trays. For more information go to: http://www.linear.com/packaging/ 3014bfb For more information www.linear.com/LT3014B 3 LT3014B ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TJ = 25°C. SYMBOL CONDITIONS Minimum Input Voltage ILOAD = 20mA ADJ Pin Voltage (Notes 2, 3) VIN = 3.3V, ILOAD = 100µA 3.3V < VIN < 80V, 100µA < ILOAD < 20mA l Line Regulation DVIN = 3.3V to 80V, ILOAD = 100µA (Note 2) l Load Regulation VIN = 3.3V, DILOAD = 100µA to 20mA (Note 2) VIN = 3.3V, DILOAD = 100µA to 20mA l ILOAD = 100µA ILOAD = 100µA l ILOAD = 1mA ILOAD = 1mA l ILOAD = 10mA ILOAD = 10mA l ILOAD = 20mA ILOAD = 20mA l ILOAD = 0mA ILOAD = 100µA ILOAD = 1mA ILOAD = 10mA ILOAD = 20mA l l l l l Dropout Voltage VIN = VOUT(NOMINAL) (Notes 4, 5) GND Pin Current VIN = VOUT(NOMINAL) (Notes 4, 6) MIN TYP 3 3.3 V 1.200 1.180 1.220 1.220 1.240 1.260 V V l Output Voltage Noise COUT = 0.47µF, ILOAD = 20mA, BW = 10Hz to 100kHz ADJ Pin Bias Current (Note 7) Ripple Rejection VIN = 7V (Avg), VRIPPLE = 0.5VP-P , fRIPPLE = 120Hz, ILOAD = 20mA Current Limit VIN = 7V, VOUT = 0V VIN = 3.3V, DVOUT = –0.1V (Note 2) l Input Reverse Leakage Current VIN = –80V, VOUT = 0V l Reverse Output Current (Note 8) VOUT = 1.22V, VIN < 1.22V (Note 2) 1 10 mV 25 40 mV mV 120 180 250 mV mV 200 270 360 mV mV 300 350 450 mV mV 350 410 570 mV mV 7 12 40 250 650 20 30 100 450 1000 µA µA µA µA µA 115 60 25 UNITS 13 4 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: The LT3014B is tested and specified for these conditions with the ADJ pin connected to the OUT pin. Note 3: Operating conditions are limited by maximum junction temperature. The regulated output voltage specification will not apply for all possible combinations of input voltage and output current. When operating at maximum input voltage, the output current range must be limited. When operating at maximum output current, the input voltage range must be limited. Note 4: To satisfy requirements for minimum input voltage, the LT3014B is tested and specified for these conditions with an external resistor divider (249k bottom, 392k top) for an output voltage of 3.3V. The external resistor divider adds a 5µA DC load on the output. Note 5: Dropout voltage is the minimum input to output voltage differential needed to maintain regulation at a specified output current. In dropout, the output voltage is equal to (VIN – VDROPOUT). MAX µVRMS 10 nA 70 dB 70 mA mA 2 6 mA 4 µA Note 6: GND pin current is tested with VIN = VOUT (nominal) and a current source load. This means the device is tested while operating in its dropout region. This is the worst-case GND pin current. The GND pin current decreases slightly at higher input voltages. Note 7: ADJ pin bias current flows into the ADJ pin. Note 8: Reverse output current is tested with the IN pin grounded and the OUT pin forced to the rated output voltage. This current flows into the OUT pin and out of the GND pin. Note 9: The LT3014B is tested and specified under pulse load conditions such that TJ @ TA. The LT3014BE is 100% tested at TA = 25°C. Performance at –40°C to 125°C is assured by design, characterization, and statistical process controls. The LT3014BI is guaranteed over the full –40°C to 125°C operating junction temperature range. The LT3014BMP is 100% tested and guaranteed over the –55°C to 125°C operating junction temperature range. Note 10: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125°C when overtemperature protection is active. Continuous operation above the specified maximum operating junction temperature may impair device reliability. 3014bfb 4 For more information www.linear.com/LT3014B LT3014B TYPICAL PERFORMANCE CHARACTERISTICS Guaranteed Dropout Voltage 600 450 500 TJ = 125°C DROPOUT VOLTAGE (mV) DROPOUT VOLTAGE (mV) 400 350 300 TJ = 25°C 250 200 150 100 500 = TEST POINTS 400 TJ ≤ 25°C 300 200 100 400 0 2 4 0 6 8 10 12 14 16 18 20 OUTPUT CURRENT (mA) 250 0 150 VIN = 6V RL = ∞ IL = 0 2 4 4 2 75 50 25 TEMPERATURE (°C) 0 100 125 IL = 100µA 1.230 1.225 1.220 1.215 1.210 1.200 –50 –25 1000 75 50 25 TEMPERATURE (°C) 0 GND PIN CURRENT (µA) GND PIN CURRENT (µA) RL = 61Ω IL = 20mA* 600 500 400 RL = 122Ω IL = 10mA* 300 200 0 1 2 3 4 5 6 7 INPUT VOLTAGE (V) 9 10 3014B G07 8 6 4 0 1 2 3 4 5 6 7 INPUT VOLTAGE (V) 9 10 ADJ Pin Bias Current 14 12 700 600 500 400 300 0 8 3014B G06 GND Pin Current vs ILOAD 10 8 6 4 2 100 8 10 0 125 200 RL = 1.22k IL = 1mA* 100 100 VIN = 3.3V 900 TJ = 25°C = 1.22V V 800 OUT 800 700 12 3014B G05 GND Pin Current TJ = 25°C 900 *FOR VOUT = 1.22V TJ = 25°C 14 RL = ∞ VOUT = 1.22V 2 3014B G04 1000 125 Quiescent Current 1.205 0 –50 –25 100 16 QUIESCENT CURRENT (µA) ADJ PIN VOLTAGE (V) 6 50 25 0 75 TEMPERATURE (°C) –25 3014B G03 ADJ PIN BIAS CURRENT (nA) QUIESCENT CURRENT (µA) 8 0 0 –50 6 8 10 12 14 16 18 20 OUTPUT CURRENT (mA) 1.235 10 IL = 100µA 100 ADJ Pin Voltage 1.240 12 IL = 1mA 200 3014B G02 Quiescent Current 14 IL = 10mA 300 50 3014B G01 16 IL = 20mA 350 50 0 Dropout Voltage 450 TJ ≤ 125°C DROPOUT VOLTAGE (mV) Typical Dropout Voltage 500 0 2 4 6 8 10 12 14 16 18 20 OUTPUT CURRENT (mA) 3014B G08 0 –50 –25 0 50 75 25 TEMPERATURE (°C) 100 125 3014B G12 3014bfb For more information www.linear.com/LT3014B 5 LT3014B TYPICAL PERFORMANCE CHARACTERISTICS Current Limit 100 90 50 40 30 20 70 60 50 40 30 20 10 0 VIN = 7V VOUT = 0V 80 60 CURRENT LIMIT (mA) CURRENT LIMIT (mA) VOUT = 0V 70 TJ = 25°C Reverse Output Current 50 REVERSE OUTPUT CURRENT (µA) Current Limit 80 10 0 2 4 –25 50 25 0 75 TEMPERATURE (°C) Reverse Output Current 5 4 3 2 75 50 25 TEMPERATURE (°C) 0 100 64 62 60 –25 0.5 75 50 25 TEMPERATURE (°C) 0 100 125 40 –10 –15 –20 –25 –30 0 25 50 75 100 125 TEMPERATURE (°C) 3014B G19 COUT = 4.7µF 30 20 COUT = 0.47µF 100 1k 10k FREQUENCY (Hz) 100k 1M 3014B G18 Output Noise Spectral Density ∆IL = 100µA TO 20mA VOUT = 1.22V –40 –50 –25 10 50 0 10 125 –35 100 9 VIN = 7V + 50mVRMS RIPPLE IL = 20mA 10 OUTPUT NOISE SPECTRAL DENSITY (µV/√Hz) –5 LOAD REGULATION (mV) MINIMUM INPUT VOLTAGE (V) ILOAD = 20mA 3.0 1.0 3 4 5 6 7 8 OUTPUT VOLTAGE (V) 60 Load Regulation 1.5 2 3014B G17 0 2.0 1 0 70 66 Minimum Input Voltage 25 75 0 50 TEMPERATURE (°C) 10 Input Ripple Rejection VIN = 7V + 0.5VP-P 70 RIPPLE AT f = 120Hz IL = 20mA 68 56 –50 125 2.5 CURRENT FLOWS INTO OUTPUT PIN 15 80 3014B G16 0 –50 –25 20 3014B G15 58 1 –25 25 0 125 RIPPLE REJECTION (dB) VIN = 0V VOUT = VADJ = 1.22V 0 –50 30 Input Ripple Rejection 6 3.5 100 72 RIPPLE REJECTION (dB) REVERSE OUTPUT CURRENT (µA) 7 35 3014B G14 3014B G13 8 ADJ PIN ESD CLAMP 5 0 –50 6 8 10 12 14 16 18 20 INPUT VOLTAGE (V) TJ = 25°C 45 VIN = 0V = VADJ V 40 OUT 3014B G20 10 COUT = 0.47µF IL = 20mA VOUT = 1.22V 1 0.1 0.01 10 100 1k 10k FREQUENCY (Hz) 100k 3014B G21 3014bfb 6 For more information www.linear.com/LT3014B LT3014B TYPICAL PERFORMANCE CHARACTERISTICS Transient Response VOUT 200µV/DIV COUT = 0.47µF IL = 20mA VOUT = 1.22V 1ms/DIV 3014B G22 LOAD CURRENT (mA) OUTPUT VOLTAGE DEVIATION (V) 10Hz to 100kHz Output Noise 0.04 0.02 0 VIN = 7V VOUT = 5V CIN = COUT = 0.47µF CERAMIC ∆ILOAD = 1mA TO 5mA –0.02 –0.04 6 4 2 0 0 200 600 400 TIME (µs) 800 1000 3014B G23 PIN FUNCTIONS (SOT-23 Package/DD Package) IN (Pin 1/Pin 8): Input. Power is supplied to the device through the IN pin. A bypass capacitor is required on this pin if the device is more than six inches away from the main input filter capacitor. In general, the output impedance of a battery rises with frequency, so it is advisable to include a bypass capacitor in battery-powered circuits. A bypass capacitor in the range of 0.1µF to 10µF is sufficient. The LT3014B is designed to withstand reverse voltages on the IN pin with respect to ground and the OUT pin. In the case of a reversed input, which can happen if a battery is plugged in backwards, the LT3014B will act as if there is a diode in series with its input. There will be no reverse current flow into the LT3014B and no reverse voltage will appear at the load. The device will protect both itself and the load. GND (Pin 2/Pins 4, 9): Ground. ADJ (Pin 4/Pin 2): Adjust. This is the input to the error amplifier. This pin is internally clamped to ±7V. It has a bias current of 4nA which flows into the pin (see curve of ADJ Pin Bias Current vs Temperature in the Typical Performance Characteristics). The ADJ pin voltage is 1.22V referenced to ground, and the output voltage range is 1.22V to 60V. OUT (Pin 5/Pin 1): Output. The output supplies power to the load. A minimum output capacitor of 0.47µF is required to prevent oscillations. Larger output capacitors will be required for applications with large transient loads to limit peak voltage transients. See the Applications Information section for more information on output capacitance and reverse output characteristics. NC (Pin 3/Pins 3, 5, 6, 7): No Connect. No Connect pins may be floated, tied to IN or tied to GND. 3014bfb For more information www.linear.com/LT3014B 7 LT3014B APPLICATIONS INFORMATION Adjustable Operation The LT3014B has an output voltage range of 1.22V to 60V. The output voltage is set by the ratio of two external resistors as shown in Figure 1. The device servos the output to maintain the voltage at the adjust pin at 1.22V referenced to ground. The current in R1 is then equal to 1.22V/R1 and the current in R2 is the current in R1 plus the ADJ pin bias current. The ADJ pin bias current, 4nA at 25°C, flows through R2 into the ADJ pin. The output voltage can be calculated using the formula in Figure 1. The value of R1 should be less than 1.62M to minimize errors in the output voltage caused by the ADJ pin bias current. The device is tested and specified with the ADJ pin tied to the OUT pin and a 5µA DC load (unless otherwise specified) for an output voltage of 1.22V. Specifications for output voltages greater than 1.22V will be proportional to the ratio of the desired output voltage to 1.22V (VOUT/1.22V). For example, load regulation for an output current change of 1mA to 20mA is –13mV typical at VOUT = 1.22V. At VOUT = 12V, load regulation is: (12V/1.22V) • (–13mV) = –128mV IN VIN OUT R2 LT3014B VOUT + ADJ GND R1 Output Capacitance and Transient Response The LT3014B is designed to be stable with a wide range of output capacitors. The ESR of the output capacitor affects stability, most notably with small capacitors. A minimum output capacitor of 0.47µF with an ESR of 3Ω or less is recommended to prevent oscillations. The LT3014B is a micropower device and output transient response will be a function of output capacitance. Larger values of output capacitance decrease the peak deviations and provide improved transient response for larger load current changes. Bypass capacitors, used to decouple individual components powered by the LT3014B, will increase the effective output capacitor value. Extra consideration must be given to the use of ceramic capacitors. Ceramic capacitors are manufactured with a variety of dielectrics, each with different behavior across temperature and applied voltage. The most common dielectrics used are specified with EIA temperature characteristic codes of Z5U, Y5V, X5R and X7R. The Z5U and Y5V dielectrics are good for providing high capacitances in a small package, but they tend to have strong voltage and temperature coefficients as shown in Figures 2 and 3. When used with a 5V regulator, a 16V 10µF Y5V capacitor can exhibit an effective value as low as 1µF to 2µF for the DC bias voltage applied and over the operating temperature range. The X5R and X7R dielectrics result in more stable characteristics and are more suitable for use as the output capacitor. The X7R type has better stability across temperature, while the X5R is less expensive and is avail20 BOTH CAPACITORS ARE 16V, 1210 CASE SIZE, 10µF 0 CHANGE IN VALUE (%) The LT3014B is a 20mA high voltage, low dropout regulator with micropower quiescent current. The device is capable of supplying 20mA at a dropout voltage of 350mV. Operating quiescent current is only 7µA. In addition to the low quiescent current, the LT3014B incorporates several protection features which make it ideal for use in battery-powered systems. The device is protected against both reverse input and reverse output voltages. In battery backup applications where the output can be held up by a backup battery when the input is pulled to ground, the LT3014B acts like it has a diode in series with its output and prevents reverse current flow. X5R –20 –40 –60 Y5V 3014B F01 –80 ( ) VOUT = 1.22V • 1 + R2 + (IADJ)(R2) R1 VADJ = 1.22V IADJ = 4nA AT 25°C OUTPUT RANGE = 1.22V TO 60V Figure 1. Adjustable Operation 8 –100 0 2 4 8 6 10 12 DC BIAS VOLTAGE (V) 14 16 3014B F02 Figure 2. Ceramic Capacitor DC Bias Characteristics 3014bfb For more information www.linear.com/LT3014B LT3014B APPLICATIONS INFORMATION The GND pin current can be found by examining the GND Pin Current curves in the Typical Performance Characteristics. Power dissipation will be equal to the sum of the two components listed above. 40 CHANGE IN VALUE (%) 20 0 X5R –20 –40 Y5V –60 –80 BOTH CAPACITORS ARE 16V, 1210 CASE SIZE, 10µF –100 –50 –25 50 25 75 0 TEMPERATURE (°C) 100 125 3014B F03 Figure 3. Ceramic Capacitor Temperature Characteristics able in higher values. Care still must be exercised when using X5R and X7R capacitors; the X5R and X7R codes only specify operating temperature range and maximum capacitance change over temperature. Capacitance change due to DC bias with X5R and X7R capacitors is better than Y5V and Z5U capacitors, but can still be significant enough to drop capacitor values below appropriate levels. Capacitor DC bias characteristics tend to improve as component case size increases, but expected capacitance at operating voltage should be verified. Voltage and temperature coefficients are not the only sources of problems. Some ceramic capacitors have a piezoelectric response. A piezoelectric device generates voltage across its terminals due to mechanical stress, similar to the way a piezoelectric accelerometer or microphone works. For a ceramic capacitor the stress can be induced by vibrations in the system or thermal transients. The LT3014B regulator has internal thermal limiting designed to protect the device during overload conditions. For continuous normal conditions the maximum junction temperature rating of 125°C must not be exceeded. It is important to give careful consideration to all sources of thermal resistance from junction to ambient. Additional heat sources mounted nearby must also be considered. For surface mount devices, heat sinking is accomplished by using the heat spreading capabilities of the PC board and its copper traces. Copper board stiffeners and plated through-holes can also be used to spread the heat generated by power devices. The following table lists thermal resistance for several different board sizes and copper areas. All measurements were taken in still air on 3/32” FR-4 board with one ounce copper. Table 1. SOT-23 Measured Thermal Resistance COPPER AREA BOARD AREA THERMAL RESISTANCE (JUNCTION-TO-AMBIENT) 2500 sq mm 2500 sq mm 2500 sq mm 125°C/W 1000 sq mm 2500 sq mm 2500 sq mm 125°C/W 225 sq mm 2500 sq mm 2500 sq mm 130°C/W 100 sq mm 2500 sq mm 2500 sq mm 135°C/W 50 sq mm 2500 sq mm 2500 sq mm 150°C/W TOPSIDE BACKSIDE Table 2. DFN Measured Thermal Resistance COPPER AREA Thermal Considerations The power handling capability of the device will be limited by the maximum rated junction temperature (125°C). The power dissipated by the device will be made up of two components: 1.Output current multiplied by the input/output voltage differential: IOUT • (VIN – VOUT) and, 2.GND pin current multiplied by the input voltage: IGND • VIN. BOARD AREA THERMAL RESISTANCE (JUNCTION-TO-AMBIENT) 2500 sq mm 2500 sq mm 2500 sq mm 40°C/W 1000 sq mm 2500 sq mm 2500 sq mm 45°C/W 225 sq mm 2500 sq mm 2500 sq mm 50°C/W 100 sq mm 2500 sq mm 2500 sq mm 62°C/W TOPSIDE BACKSIDE For the DFN package, the thermal resistance junction-tocase (θJC), measured at the Exposed Pad on the back of the die, is 16°C/W. 3014bfb For more information www.linear.com/LT3014B 9 LT3014B APPLICATIONS INFORMATION Continuous operation at large input/output voltage differentials and maximum load current is not practical due to thermal limitations. Transient operation at high input/ output differentials is possible. The approximate thermal time constant for a 2500sq mm 3/32" FR-4 board with maximum topside and backside area for one ounce copper is 3 seconds. This time constant will increase as more thermal mass is added (i.e. vias, larger board, and other components). For an application with transient high power peaks, average power dissipation can be used for junction temperature calculations as long as the pulse period is significantly less than the thermal time constant of the device and board. Calculating Junction Temperature Example 1: Given an output voltage of 5V, an input voltage range of 24V to 30V, an output current range of 0mA to 20mA, and a maximum ambient temperature of 50°C, what will the maximum junction temperature be? The power dissipated by the device will be equal to: IOUT(MAX) • (VIN(MAX) – VOUT) + (IGND • VIN(MAX)) Example 2: Given an output voltage of 5V, an input voltage of 48V that rises to 72V for 5ms(max) out of every 100ms, and a 5mA load that steps to 20mA for 50ms out of every 250ms, what is the junction temperature rise above ambient? Using a 500ms period (well under the time constant of the board), power dissipation is as follows: P1(48V in, 5mA load) =5mA • (48V – 5V) + (100µA • 48V) = 0.22W P2(48V in, 20mA load) = 20mA • (48V – 5V) + (0.55mA • 48V) = 0.89W P3(72V in, 5mA load) =5mA • (72V – 5V) + (100µA • 72V) = 0.34W P4(72V in, 20mA load) =20mA • (72V – 5V) + (0.55mA • 72V) = 1.38W Operation at the different power levels is as follows: 76% operation at P1, 19% for P2, 4% for P3, and 1% for P4. PEFF = 76%(0.22W) + 19%(0.89W) + 4%(0.34W) + 1%(1.38W) = 0.36W IOUT(MAX) = 20mA With a thermal resistance in the range of 40°C/W to 62°C/W, this translates to a junction temperature rise above ambient of 20°C. VIN(MAX) = 30V Protection Features where: IGND at (IOUT = 20mA, VIN = 30V) = 0.55mA So: P = 20mA • (30V – 5V) + (0.55mA • 30V) = 0.52W The thermal resistance for the DFN package will be in the range of 40°C/W to 62°C/W depending on the copper area. So the junction temperature rise above ambient will be approximately equal to: 0.52W • 50°C/W = 26°C The maximum junction temperature will then be equal to the maximum junction temperature rise above ambient plus the maximum ambient temperature or: TJMAX = 50°C + 26°C = 76°C The LT3014B incorporates several protection features which make it ideal for use in battery-powered circuits. In addition to the normal protection features associated with monolithic regulators, such as current limiting and thermal limiting, the device is protected against reverseinput voltages, and reverse voltages from output to input. Current limit protection and thermal overload protection are intended to protect the device against current overload conditions at the output of the device. For normal operation, the junction temperature should not exceed 125°C. The input of the device will withstand reverse voltages of 80V. Current flow into the device will be limited to less than 6mA (typically less than 100µA) and no negative 3014bfb 10 For more information www.linear.com/LT3014B LT3014B APPLICATIONS INFORMATION The ADJ pin can be pulled above or below ground by as much as 7V without damaging the device. If the input is left open circuit or grounded, the ADJ pin will act like an open circuit when pulled below ground, and like a large resistor (typically 100k) in series with a diode when pulled above ground. If the input is powered by a voltage source, pulling the ADJ pin below the reference voltage will cause the device to current limit. This will cause the output to go to an unregulated high voltage. Pulling the ADJ pin above the reference voltage will turn off all output current. In situations where the ADJ pin is connected to a resistor divider that would pull the ADJ pin above its 7V clamp voltage if the output is pulled high, the ADJ pin input current must be limited to less than 5mA. For example, a resistor divider is used to provide a regulated 1.5V output from the 1.22V reference when the output is forced to 60V. The top resistor of the resistor divider must be chosen to limit the current into the ADJ pin to less than 5mA when the ADJ pin is at 7V. The 53V difference between the OUT and ADJ pins divided by the 5mA maximum current into the ADJ pin yields a minimum top resistor value of 10.6k. In circuits where a backup battery is required, several different input/output conditions can occur. The output voltage may be held up while the input is either pulled to ground, pulled to some intermediate voltage, or is left open circuit. Current flow back into the output will follow the curve shown in Figure 4. The rise in reverse output current above 7V occurs from the breakdown of the 7V clamp on the ADJ pin. With a resistor divider on the regulator output, this current will be reduced depending on the size of the resistor divider. When the IN pin of the LT3014B is forced below the OUT pin or the OUT pin is pulled above the IN pin, input current will typically drop to less than 2µA. This can happen if the input of the LT3014B is connected to a discharged (low voltage) battery and the output is held up by either a backup battery or a second regulator circuit. 50 REVERSE OUTPUT CURRENT (µA) voltage will appear at the output. The device will protect both itself and the load. This provides protection against batteries which can be plugged in backward. TJ = 25°C 45 VIN = 0V = VADJ V 40 OUT ADJ PIN ESD CLAMP 35 30 25 20 CURRENT FLOWS INTO OUTPUT PIN 15 10 5 0 0 1 2 3 4 5 6 7 8 OUTPUT VOLTAGE (V) 9 10 3014B F04 Figure 4. Reverse Output Current 3014bfb For more information www.linear.com/LT3014B 11 LT3014B TYPICAL APPLICATIONS LT3014B Automotive Application VIN 12V (LATER 42V) + 1µF IN NO PROTECTION DIODE NEEDED! OUT LT3014B R1 1µF ADJ GND R2 LOAD: CLOCK, SECURITY SYSTEM ETC LT3014B Telecom Application VIN 48V (72V TRANSIENT) IN 1µF OUT LT3014B ADJ GND R1 NO PROTECTION DIODE NEEDED! R2 1µF + LOAD: SYSTEM MONITOR ETC – BACKUP BATTERY 3014B TA05 3014bfb 12 For more information www.linear.com/LT3014B LT3014B PACKAGE DESCRIPTION Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. 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 3014bfb For more information www.linear.com/LT3014B 13 LT3014B PACKAGE DESCRIPTION Please refer to http://www.linear.com/designtools/packaging/ for the most recent package drawings. DD Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698 Rev C) 0.70 ±0.05 3.5 ±0.05 1.65 ±0.05 2.10 ±0.05 (2 SIDES) PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 2.38 ±0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF 3.00 ±0.10 (4 SIDES) R = 0.125 TYP 5 0.40 ±0.10 8 1.65 ±0.10 (2 SIDES) 0.75 ±0.05 4 0.25 ±0.05 1 (DD8) DFN 0509 REV C 0.50 BSC 2.38 ±0.10 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-1) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON TOP AND BOTTOM OF PACKAGE 3014bfb 14 For more information www.linear.com/LT3014B LT3014B REVISION HISTORY (Revision history begins at Rev B) REV DATE DESCRIPTION PAGE NUMBER B 11/14 Add MP-Grade 2, 3, 4 Modified Related Parts 16 3014bfb 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. For more information www.linear.com/LT3014B 15 LT3014B TYPICAL APPLICATIONS Constant Brightness for Indicator LED over Wide Input Voltage Range RETURN IN OUT LT3014B 1µF –48V 1µF ADJ GND ILED = 1.22V/RSET –48V CAN VARY FROM –3.3V TO –80V RSET 3014B TA06 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT1129 700mA, Micropower, LDO VIN: 4.2V to 30V, VOUT(MIN) = 3.75V, VDO = 0.4V, IQ = 50µA, ISD = 16µA, DD, SOT-223, S8, TO220, TSSOP-20 Packages LT1175 500mA, Micropower Negative LDO VIN: –20V to –4.3V, VOUT(MIN) = –3.8V, VDO = 0.50V, IQ = 45µA, ISD = 10µA, DD, SOT-223, S8 Packages LT1185 3A, Negative LDO VIN: –35V to –4.2V, VOUT(MIN) = –2.40V, VDO = 0.80V, IQ = 2.5mA, ISD < 1µA, TO220-5 Package LT1761 100mA, Low Noise Micropower, LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 20µA, ISD < 1µA, ThinSOT Package LT1762 150mA, Low Noise Micropower, LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 25µA, ISD < 1µA, MS8 Package LT1763 500mA, Low Noise Micropower, LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 30µA, ISD < 1µA, S8 and DFN Packages LT1764/LT1764A 3A, Low Noise, Fast Transient Response, LDO VIN: 2.7V to 20V, VOUT(MIN) = 1.21V, VDO = 0.34V, IQ = 1mA, ISD < 1µA, DD, TO220 Packages LTC1844 150mA, Very Low Dropout LDO VIN: 1.6V to 6.5V, VOUT(MIN) = 1.25V, VDO = 0.08V, IQ = 40µA, ISD < 1µA, ThinSOT Package LT1962 300mA, Low Noise Micropower, LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.27V, IQ = 30µA, ISD < 1µA, MS8 Package LT1963/LT1963A 1.5A, Low Noise, Fast Transient Response, LDO VIN: 2.1V to 20V, VOUT(MIN) = 1.21V, VDO = 0.34V, IQ = 1mA, ISD < 1µA, DD, TO220, SOT-223 and S8 Packages LT1964 200mA, Low Noise Micropower, Negative LDO VIN: –1.9V to –20V, VOUT(MIN) = –1.21V, VDO = 0.34V, IQ = 30µA, ISD = 3µA, ThinSOT and DFN Packages LT3010 50mA, 80V, Low Noise Micropower, LDO VIN: 3V to 80V, VOUT(MIN) = 1.28V, VDO = 0.3V, IQ = 30µA, ISD < 1µA, MS8E Package LT3020 100mA, Low VIN, Low VOUT Micropower, VLDO VIN: 0.9V to 10V, VOUT(MIN) = 0.20V, VDO = 0.15V, IQ = 120µA, ISD < 1µA, DFN, MS8 Packages LT3023 Dual 100mA, Low Noise Micropower, LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 40µA, ISD < 1µA, DFN, MS10 Packages LT3024 Dual 100mA/500mA, Low Noise Micropower, LDO VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 60µA, ISD < 1µA, DFN, TSSOP-16E Packages LT3027 Dual 100mA, Low Noise LDO with Independent Inputs VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 40µA, ISD < 1µA, DFN, MS10E Packages LT3028 Dual 100mA/500mA, Low Noise LDO with Independent Inputs VIN: 1.8V to 20V, VOUT(MIN) = 1.22V, VDO = 0.30V, IQ = 60µA, ISD < 1µA, DFN, TSSOP-16E Packages 3014bfb 16 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 For more information www.linear.com/LT3014B (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com/LT3014B LT 1114 REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2006