lt3508euf-trpbf Linear Technology Corporation, lt3508euf-trpbf Datasheet

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... The low current (<2μA) shutdown mode enables easy power management in battery-powered systems. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. ON OFF SHDN ...

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... LT3508EFE#TRPBF LT3508IFE#PBF LT3508IFE#TRPBF LT3508HFE#PBF LT3508HFE#TRPBF LT3508EUF#PBF LT3508EUF#TRPBF LT3508IUF#PBF LT3508IUF#TRPBF LT3508HUF#PBF LT3508HUF#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges.*Temperature grades are 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 V Quiescent Current IN1 V Quiescent Current IN2 Shutdown Current ( IN1 IN2 FB Voltage FB ...

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LT3508 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency OUT 25° 700kHz V = 12V 24V 32V 0.5 1 LOAD ...

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TYPICAL PERFORMANCE CHARACTERISTICS Quiescent Current 5 25°C A 4.5 V IN1 4.0 3.5 3.0 2.5 2.0 1.5 1.0 V IN2 0 INPUT VOLTAGE (V) 3508 G10 Switch Voltage Drop ...

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LT3508 PIN FUNCTIONS BOOST1, BOOST2: The BOOST pins are used to provide drive voltages, higher than the input voltage, to the internal NPN power switches. Tie through a diode to a 2.8V or higher supply, such ...

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BLOCK DIAGRAM 1.2μA TRACK/SS 0.75V + SLOPE SLAVE OSC CLK + – 0.625V GND Figure 1. Block Diagram of the LT3508 with Associated External Components (One of Two Switching Regulators Shown) ...

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LT3508 OPERATION The LT3508 is a dual constant frequency, current mode regulator with internal power switches. Operation can be best understood by referring to the Block Diagram. If the SHDN pin is tied to ground, the LT3508 is shut down ...

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APPLICATIONS INFORMATION Setting 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 = – 1 ...

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LT3508 APPLICATIONS INFORMATION V OUT 100mV/DIV (AC 500mA/DIV 2μs/DIV Figure 2. Operation Below 10V, V IN(PS 1.5MHz SW V OUT 100mV/DIV (AC 500mA/DIV 2μs/DIV Figure 3. Operation Above V ...

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APPLICATIONS INFORMATION The optimum inductor for a given application may differ from the one indicated by this simple design guide. A larger value inductor provides a higher maximum load current, and reduces the output voltage ripple. If your load is ...

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LT3508 APPLICATIONS INFORMATION the input capacitor’s RMS current actually decreases as the out-of-phase current cancels the current drawn by the higher power channel. Considering that the maximum load current from a single channel is ~1.4A, RMS ripple current will always ...

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APPLICATIONS INFORMATION Diode Selection The catch diode (D1 from Figure 1) conducts current only during switch off time. Average forward current in normal operation can be calculated from – V OUT IN OUT = I D ...

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LT3508 APPLICATIONS INFORMATION The minimum operating voltage of an LT3508 application is limited by the undervoltage lockout (≈3.7V) and by the maximum duty cycle. The boost circuit also limits the minimum input voltage for proper start-up. If the input voltage ...

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APPLICATIONS INFORMATION is much lower than the switching frequency. A phase-lead capacitor (C ) across the feedback divider may improve PL the transient response. LT3508 CURRENT MODE V SW POWER STAGE ERROR g = 2.5S m AMPLIFIER R1 FB – ...

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LT3508 APPLICATIONS INFORMATION Output Tracking and Sequencing Complex output tracking and sequencing between channels can be implemented using the LT3508’s TRACK/SS and PG pins. Figure 8 shows several confi gurations for output tracking and sequencing of 5V and 3.3V applications. ...

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APPLICATIONS INFORMATION Ratiometric tracking is achieved in Figure 8b by connecting both the TRACK/SS pins together. In this confi guration the TRACK/SS pin source current is doubled (2.4μA) which must be taken into account when calculating the output rise time. ...

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LT3508 APPLICATIONS INFORMATION applications or in battery back-up systems where a battery or some other supply is diode OR-ed with the LT3508’s pin is allowed to fl oat and the SHDN pin output. If the held high ...

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APPLICATIONS INFORMATION High Temperature Considerations The die temperature of the LT3508 must be lower than the maximum rating of 125°C (150°C for the H grade). This is generally not a concern unless the ambient temperature is above 85°C. For higher ...

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LT3508 TYPICAL APPLICATIONS 3.3V and 5V Dual Output Step-Down Converter with Output Sequencing V IN 5.7V TO 36V OUT1 3.3V 1.4A R1 35.7k 11.5k C4 22μ C5: X5R OR X7R D1, D2: MMSD4148 D3: DIODES INC. B140 D4: ...

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TYPICAL APPLICATIONS V IN 14V TO 36V OUT2 L1 15μH OUT1 12V 1.4A* R1 154k 11.0k C4 4.7μF 1MHz, 5V and 12V Outputs ON OFF C1 4.7μF SHDN IN1 IN2 BOOST1 BOOST2 C2 0.1μF SW1 SW2 R2 ...

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LT3508 PACKAGE DESCRIPTION 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ARE IN 3. DRAWING ...

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... ON THE TOP AND BOTTOM OF PACKAGE 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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... Dual Two Phase SENSE with Output Tracking LTC3737 Dual Two Phase SENSE Output Tracking trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 5V, 1.8V Output from PCI Express C1 4.7μ ...