lt3501efe-trpbf Linear Technology Corporation, lt3501efe-trpbf Datasheet

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... SHDN pin the entire part can be placed in a low quiescent current shutdown mode. The LT3501 is available in a 20-lead TSSOP package with exposed leadframe for low thermal resistance. , LT, LTC, and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners ...

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... T V ......................................................................±1mA C1/2 Operating Junction Temperature Range LT3501EFE (Notes 2, 8) ..................... –40°C to 125°C LT3501IFE (Notes 2, 8) ...................... –40°C to 125°C Storage Temperature Range ................... –65°C to 150°C Lead Temperature (Soldering, 10 sec) .................. 300°C ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T unless otherwise specifi ...

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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LT3501EFE is guaranteed to meet performance specifi cations from 0°C to 125°C junction temperature. Specifi cations over the –40°C to 125°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. The LT3501IFE is guaranteed and tested over the full – ...

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LT3501 ELECTRICAL CHARACTERISTICS Note 6: The IND to V maximum current is defi ned as the value of OUT current fl owing from the IND pin to the V pin which resets the switch OUT latch when the V pin ...

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TYPICAL PERFORMANCE CHARACTERISTICS Soft-Start to Feedback Offset Voltage vs Temperature –1 –2 –3 –4 –50 – 100 TEMPERATURE (°C) 3501 G08 Power Good Sink Current vs Temperature 1000 950 900 850 ...

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LT3501 TYPICAL PERFORMANCE CHARACTERISTICS External Sync Duty Cycle Range vs External Sync Frequency 100 90 MAXIMUM CLOCK 80 DUTY CYCLE MINIMUM CLOCK 20 DUTY CYCLE 10 0 250 500 1000 1250 750 1500 FREQUENCY (kHz) ...

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TYPICAL PERFORMANCE CHARACTERISTICS Dropout Operation 6 LOAD = OUT 3.3V OUT 2 FREQUENCY 1 1.5MHz 250kHz 0 2 2.5 3 3.5 4 4.5 5 5.5 6 INPUT VOLTAGE (V) 3501 G27 ...

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LT3501 PIN FUNCTIONS This indicates that the output is overloaded and current is pulled from the SS pin, reducing the regulation point. FB1/FB2 (Pins 17, 14): The FB pin is the negative input to the error amplifi er. The output ...

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BLOCK DIAGRAM R /SYNC IN1 INTERNAL REGULATOR AND REFERENCE 3µA 7µA SHDN + – + SHUTDOWN 1.28V COMPARATOR POR UNDERVOLTAGE TSD SOFT-START GND COMPARATOR Figure 1. Block Diagram (One of Two Switching Regulators Shown) The LT3501 is ...

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LT3501 BLOCK DIAGRAM will be generated at the incoming frequency on the rising edge of the synchronization pulse with switch 1 in phase with the synchronization signal. In addition, the internal slope compensation will be automatically adjusted to pre- vent ...

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APPLICATIONS INFORMATION Choosing the Output Voltage The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the 1% resis- tors according to: ⎛ ⎞ V OUT = • – ...

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LT3501 APPLICATIONS INFORMATION maximum duty cycle. The duty cycle is the fraction of time that the internal switch is on during a clock cycle. Unlike most fi xed frequency regulators, the LT3501 will not switch off at the end of ...

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APPLICATIONS INFORMATION and its saturation current should be about 30% higher. To keep effi ciency high, the series resistance (DCR) should be less than 0.05Ω. For applications with a duty cycle of about 50%, the induc- tor value should be ...

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LT3501 APPLICATIONS INFORMATION may result in discontinuous mode operation, which is okay, but further reduces maximum load current. For details of maximum output current and discontinuous mode operation, see Linear Technology Application Note 44. Finally, for duty cycles greater than ...

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APPLICATIONS INFORMATION either clamp the input voltage or dampen the tank circuit by adding a lossy capacitor in parallel with the ceramic capacitor. For details, see Application Note 88. Output Capacitor Selection Typically step-down regulators are easily compensated with an ...

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LT3501 APPLICATIONS INFORMATION Table 2 VENDOR TYPE Taiyo Yuden Ceramic X5R, X7R AVX Ceramic X5R, X7R Tantalum Kemet Tantalum TA Organic AL Organic Sanyo TA/AL Organic Panasonic AL Organic TDK Ceramic X5R, X7R Catch Diode The diode D1 conducts current ...

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APPLICATIONS INFORMATION BST LT3501 GND V – BST SW OUT BST(MAX) IN OUT (5a LOWEST > 3V OUT BST V ...

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LT3501 APPLICATIONS INFORMATION the output capacitor integrates this current, and that the capacitor on the V pin (C ) integrates the error ampli fi er output current, resulting in two poles in ...

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APPLICATIONS INFORMATION If the synchronization signal powers high impedance state (Hi-Z), connect a resistor from the R ground. The equivalent resistance seen from the R pin to ground will set the start-up frequency. If the synchronization signal ...

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LT3501 APPLICATIONS INFORMATION At power-up, a reset signal sets the soft-start latch and discharges both SS pins to approximately 0V to ensure proper start-up. When both SS pins are fully discharged the latch is reset and the internal 3.25µA current ...

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APPLICATIONS INFORMATION Independent Start-Up V OUT1 0.5V/DIV PG1 V OUT2 0.5V/DIV PG2 5ms/DIV 3.3V SS1 V OUT1 0.1µF LT3501 PG1 SS2 V 1.8V OUT2 0.22µF PG2 (9a) Output Sequencing PG2 10ms/DIV SS1 0.1µF LT3501 SS2 0.1µF (9d) Ratiometric Start-Up PG1 ...

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LT3501 APPLICATIONS INFORMATION 6V TO 24V 3.3µH PMEG4005 V OUT1 5V 47µF 42.3k 8.06k 10pF Figure 10. 5V and 1.2V 2-Stage Step-Down Converter with Output Sequencing inductor size by allowing an increase in frequency. A dual step down application (Figure ...

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APPLICATIONS INFORMATION LT3501 GND (11a) Figure 11. Subtracting the Current when the Switch is On (11a) from the Current when the Switch is Off (11b) Reveals the Path of the High Frequency Switching Current (11c). Keep this ...

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LT3501 APPLICATIONS INFORMATION LT3501. Place additional vias near the catch diodes. Adding more copper to the top and bottom layers and tying this copper to the internal planes with vias can further reduce thermal resistance. With these steps, the thermal ...

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TYPICAL APPLICATIONS V IN 12V 4.7µF PMEG4005 V OUT1 5V 47µF 42.3k 8.06k 16.9k 7.68k 25V IN 1.5µH PMEG4005 V OUT1 3.3V 6A 47µF 24.9k ×2 8.06k 5V and 2.5V with Absolute Tracking V V IN1 IN2 ...

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LT3501 TYPICAL APPLICATIONS PMEG4005 V OUT1 3.3V 6A 47µF 24.9k ×2 8.06k Dual LT3501 Synchronized 3.3V/12A Output, 3MHz Effective Switch Frequency V IN 5.5V TO 24V 10µF PMEG4005 V OUT1 3.3V 26 1.25MHz Single 3.3V/6A Low Ripple Output V 4.5V ...

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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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. FE Package 20-Lead Plastic TSSOP (4 ...

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... High Effi ciency Step-Down OUT DC/DC Converter LTC3548 Dual 400mA/800mA, 2.25MHz Synchronous Step-Down DC/DC Converters Burst Mode is a registered trademark of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...