LT3570EFE#PBF Linear Technology, LT3570EFE#PBF Datasheet
LT3570EFE#PBF
Specifications of LT3570EFE#PBF
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LT3570EFE#PBF Summary of contents
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... The LDO controller is capable of delivering up to 10mA of base current to an external NPN transistor. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. BIAS IN3 ...
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... TAPE AND REEL LT3570EUF#PBF LT3570EUF#TRPBF LT3570IUF#PBF LT3570IUF#TRPBF LT3570EFE#PBF LT3570EFE#TRPBF LT3570IFE#PBF LT3570IFE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Minimum Operating Voltage (V ) IN1 Minimum Operating Voltage (V ) IN2 Shutdown Current (Note 4) V Quiescent Current IN1 V Quiescent Current IN2 V Quiescent Current IN3 Bias ...
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LT3570 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER SW2 Error Amplifi Transconductance Error Amplifi Voltage Gain V Pin Switching Threshold SW2 Current Gain C2 SW2 Current Limit SW2 V ...
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TYPICAL PERFORMANCE CHARACTERISTICS V Quiescent Current IN1 vs Temperature 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0 –50 – 100 125 TEMPERATURE (°C) 3570 G04 Bias Pin Current vs Temperature 3.0 2.5 2.0 1.5 1.0 0.5 ...
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LT3570 TYPICAL PERFORMANCE CHARACTERISTICS SW2 Current Limit vs Duty Cycle 3.0 2.5 2.0 1.5 1.0 0 DUTY CYCLE (%) BOOST Pin Current vs Switch Current 25° ...
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PIN FUNCTIONS (QFN/TSSOP) V (Pins 1,2/Pin 14): Input Voltage for the Buck Regulator. IN2 This pin also supplies the current to the internal circuitry of the LT3570. This pin must be locally bypassed with a capacitor. SW2 (Pin 3/Pin15): Switch ...
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LT3570 BLOCK DIAGRAM 8 3570fb ...
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OPERATION The LT3570 is a constant frequency, current mode, buck converter and boost converter with an NPN LDO regula- tor. Operation can be best understood by referring to the Block Diagram. If all of the SHDN pins are held low, ...
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... For details of maximum output current and discontinuous mode operation, see Linear Technology’s Application Note 44. Finally, for duty cycles greater than 50% (V inductance is required to avoid subharmonic oscillations, see Application Note 19. ...
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APPLICATIONS INFORMATION to 1.2A at DC2 = 0.8. The maximum output current is a function of the chosen inductor value: Δ – OUT2(MAX) LIM2 1.5 • 1– 0.25 • DC2 Choosing an inductor value ...
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LT3570 APPLICATIONS INFORMATION and small circuit size, are therefore an option. You can estimate output ripple with the following equations: Δ for ceramic capacitors RIPPLE 8 • f • C OUT and = ΔI V • ESR ...
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APPLICATIONS INFORMATION into a tight local loop, minimizing EMI. The input capaci- tor must have low impedance at the switching frequency to do this effectively and it must have an adequate ripple current rating. The RMS input current is: ( ...
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LT3570 APPLICATIONS INFORMATION Boost Diode Selection A Schottky diode is recommended for use with the LT3570 inverter/boost regulator. The Microsemi UPS120 is a very good choice. Where the input to output voltage differen- tial exceeds 20V, use the UPS140 (a ...
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APPLICATIONS INFORMATION compensation resistor usually in the range 50k. A good technique to compensate a new application is to use a 50k potentiometer in place of R 1nF capacitor for ...
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LT3570 APPLICATIONS INFORMATION Oscillator The free-running frequency is set through a resistor from the R pin to ground. The oscillator frequency seen in Figure 4. The oscillator can be synchronized with an external clock applied to ...
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... IC and into a copper plane with as much area as possible. Related Linear Technology Publications Application notes 19, 35, 44, 76 and 88 contain more detailed descriptions and design information for buck regulators and other switching regulators. The LT1375 data sheet has a more extensive discussion of output ripple, loop compensation, and stability testing ...
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LT3570 TYPICAL APPLICATIONS 28V C9 10μF SHDN1 SHDN2 SHDN3 D1 V OUT1 8V 250mA R1 105k C1 10μF R2 11.5k 10nF V IN 12V C9 10μ 47μH V OUT1 34V R1 442k C1 10μF ...
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... DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. UF Package 24-Lead Plastic QFN (4mm × ...
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... LT3500 40V, 2A, 2.4MHz Step-Down DC/DC Converter and LDO Controller LT3507 36V, 2.5MHz Triple (2.4A, 1.5A, 1.5A) Step-Down DC/DC Converter and LDO Controller ThinSOT is a trademark of Linear Technology Corporation. 20 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...