LT3500IMSE#PBF Linear Technology, LT3500IMSE#PBF Datasheet
LT3500IMSE#PBF
Specifications of LT3500IMSE#PBF
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LT3500IMSE#PBF Summary of contents
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... The LT3500’s low current shutdown mode (<12μA) enables easy power management in battery-powered systems. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Switching Converter Effi ciency ...
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... LT3500IDD#TRPBF LT3500HDD#PBF LT3500HDD#TRPBF LT3500EMSE#PBF LT3500EMSE#TRPBF LT3500IMSE#PBF LT3500IMSE#TRPBF LT3500HMSE#PBF LT3500HMSE#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 SHDN Threshold SHDN Source Current SHDN Current Hysterisis Minimum Input Voltage (Note 3) Supply Shutdown Current Supply Quiescent Current FB Voltage FB Bias Current Error Amplifi ...
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LT3500 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER LFB Voltage LFB Line/Load Regulation SS to LFB Offset (V – LFB LFB Bias Current LDRV Dropout (V – VIN LDRV LDRV Maximum ...
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TYPICAL PERFORMANCE CHARACTERISTICS Shutdown Input Currents vs Temperature 0.9V SHDN 0.7V SHDN –50 – 100 125 TEMPERATURE (°C) 3500 G04 Soft-Start Source Current vs Temperature ...
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LT3500 TYPICAL PERFORMANCE CHARACTERISTICS Peak Switch Current vs Temperature 3.5 3.4 3.3 MSE PACKAGE 3.2 3.1 3.0 DD PACKAGE 2.9 2.8 2.7 2.6 2.5 –50 – 100 125 TEMPERATURE (°C) 3500 G13 Minimum Switching Times 300 ...
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TYPICAL PERFORMANCE CHARACTERISTICS LDRV Dropout Voltage vs Temperature 1. 5mA LDRV 1.45 1.40 1.35 1.30 1.25 1.20 1.15 1.10 1.05 1.00 –50 50 100 125 150 – TEMPERATURE (°C) 3500 G22 PIN FUNCTIONS V : ...
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LT3500 PIN FUNCTIONS Driving the R /SYNC pin with an external clock signal T will synchronize the switch to the applied frequency. Synchronization occurs on the rising edge of the clock signal after the clock signal is detected. Each rising ...
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BLOCK DIAGRAM LT3500 3500fc 9 ...
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LT3500 OPERATION The LT3500 is a constant frequency, current mode buck converter with an internal 2.3A switch plus a linear regula- tor with 13mA output capability. Control of both outputs is achieved with a common SHDN pin, internal regulator, oscillator, ...
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OPERATION V undervoltage detection or thermal shutdown will IN set the soft-start latch, resulting in a complete soft-start sequence. The switch driver operates from either the V age. An external diode and capacitor are used to generate a drive voltage ...
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LT3500 APPLICATIONS INFORMATION The following example along with the data in Table 1 illustrates the tradeoffs of switch frequency selection. Example 25V 3.3V OUT1 OUT1 Temperature = 0°C to 85° 185ns (85°C ...
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APPLICATIONS INFORMATION Note that the LT3500 will regulate if the input voltage is taken above the calculated maximum voltage as long as maximum ratings of the V and BST pins are not violated. IN However operation in this region of ...
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... For details of maximum output current and discontinuous mode operation, see Linear Technology Application Note 44. Finally, for duty cycles greater than 50% (V > 0.5), there is a minimum inductance required to avoid subharmonic oscillations ...
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APPLICATIONS INFORMATION The frequency ratio, and maximum load IN OUT1 current requirement of the LT3500 along with the input supply source impedance, determine the energy storage requirements of the input capacitor. Determine the worst- case condition for ...
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LT3500 APPLICATIONS INFORMATION the value of output capacitance required. Also, the current mode control loop doesn’t require the presence of output capacitor series resistance (ESR). For these reasons, you are free to use ceramic capacitors to achieve very low output ...
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APPLICATIONS INFORMATION The only reason to consider a larger diode is the worst- case condition of a high input voltage and shorted output. With a shorted condition, diode current will increase to a typical value of 3A, determined by the ...
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LT3500 APPLICATIONS INFORMATION The boost circuit can also run directly from a DC voltage that is higher than the input voltage by more than 2.5V Figure 5d. The diode is used to prevent damage to the LT3500 in ...
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APPLICATIONS INFORMATION current proportional to the voltage at the V the output capacitor integrates this current, and that the capacitor on the V pin (C ) integrates the error amplifi output current, resulting in two poles in ...
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LT3500 APPLICATIONS INFORMATION If the synchronization signal changes between high and low impedance states during power up (V the synchronization circuitry to the LT3500 as shown in the Typical Applications section. This will allow the LT3500 to start up with ...
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APPLICATIONS INFORMATION At power-up, a reset signal sets the soft-start latch and discharges the SS pin to approximately 0V to ensure proper start-up. When the SS pin is fully discharged the latch is reset and the internal 2.75μA current source ...
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LT3500 APPLICATIONS INFORMATION V OUT2 AC COUPLED 20mV/DIV LOAD STEP 2.5mA TO 7.5mA 5mA/DIV 20μs/DIV Figure 9. Linear Regulator Transient Response To compensate the linear regulator, simply add a ceramic capacitor from the LDRV pin to ground. Typical values range ...
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... IC sees as ambient temperature. See the LT1767 data sheet’s Thermal Considerations section. Other Linear Technology Publications Application notes AN19, AN35 and AN44 contain more detailed descriptions and design information for buck regulators and other switching regulators. The LT1376 data sheet has a more extensive discussion of output ripple, loop compensation and stability testing ...
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LT3500 TYPICAL APPLICATIONS High Effi ciency Linear Regulator 4.5V TO 36V V BST IN C1 LT3500 2.2μF SW SHDN 0.47μF R SYNC LDRV 220pF LFB GND R6 R5 40.2k 49.9k 5V/1.5A, ...
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PACKAGE DESCRIPTION 3.50 ±0.05 2.10 ±0.05 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING IS NOT A JEDEC ...
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LT3500 PACKAGE DESCRIPTION 2.845 0.102 (.112 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. ...
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... Corrected Pin Confi guration for MSE 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. ...
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... LTC3548 Dual 400mA/800mA, 2.25MHz Synchronous Step-Down DC/DC Converter LT3680 36V, 3. 2.4MHz High Effi ciency Step-Down DC/DC OUT Converter 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 ● 1.8V/2A Step-Down Regulator ...