LTC1871-1
Wide Input Range, No RSENSE™ Current Mode Boost, Flyback and SEPIC Controller
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Overview
Features and Benefits
- High Efficiency (No Sense Resistor Required)
- Wide Input Voltage Range: 2.5V to 36V
- Current Mode Control Provides Excellent Transient Response
- High Maximum Duty Cycle (92% Typ)
- ±2% RUN Pin Threshold with 100mV Hysteresis
- ±1% Internal Voltage Reference
- Ultra Low Pulse Skip Threshold for Wide Input Range Applications
- Micropower Shutdown: IQ = 10μA
- Programmable Operating Frequency (50kHz to 1MHz) with One External Resistor
- Synchronizable to an External Clock Up to 1.3 × fOSC
- User-Controlled Pulse Skip or Burst Mode® Operation
- Internal 5.2V Low Dropout Voltage Regulator Output Overvoltage Protection
- Capable of Operating with a Sense Resistor for High
- Output Voltage Applications
- Small 10-Lead MSOP Package
Product Details
The LTC1871-1 is a wide input range, current mode, boost, flyback or SEPIC controller that drives an Nchannel power MOSFET and requires very few external components. It eliminates the need for a current sense resistor by utilizing the power MOSFET’s on-resistance, thereby maximizing efficiency. Higher output voltage applications are possible with the LTC1871-1 by connecting the SENSE pin to a resistor in the source of the power MOSFET.
The IC’s operating frequency can be set with an external resistor over a 50kHz to 1MHz range, and can be synchronized to an external clock using the MODE/SYNC pin.
The LTC1871-1 differs from the LTC1871 by having a lower pulse skip threshold, making it ideal for applications requiring constant frequency operation at light loads. The lower pulse skip threshold also helps maintain constant frequency operation in applications with a wide input voltage range. For applications requiring primary-to-secondary side isolation, please refer to the LTC1871 datasheet.
The LTC1871-1 is available in the 10-lead MSOP package.
| Vin Range | INTVcc | Features | |
| LTC1871 | 2.5V to 36V | 5.2V | - |
| LTC1871-1 | 2.5V to 36V | 5.2V | Lower Burst Mode Threshold (0.195V vs. 0.3V) |
| LTC1871-7 | 6V to 36V | 7V | Drives 6V Gate N-Channel MOSFETs |
| LTC1871X | 2.5V to 36V | 5.2V | 175°C Junction Temp, 100% Tested at 175°C |
Applications
- Telecom Power Supplies
- Portable Electronic Equipment
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation & Resources
-
R384 Reliability Data3/26/2018
-
DC1225A - Demo Manual9/24/2009
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
LTspice Simulations
Models for the following parts are available in LTspice:
LTC1871
LTC1871-1
LTC1871-7
Product Recommendations
LTC1871-1 Companion Parts
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
| Part Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
|---|---|---|---|---|
| LTC1871EMS-1#PBF | Material Declaration | Reliability Data | 10-Lead MSOP | |
| LTC1871EMS-1#TRPBF | Material Declaration | Reliability Data | 10-Lead MSOP | |
| LTC1871IMS-1#PBF | Material Declaration | Reliability Data | 10-Lead MSOP | |
| LTC1871IMS-1#TRPBF | Material Declaration | Reliability Data | 10-Lead MSOP | |
| Wafer Fabrication Data | R384 Reliability Data |
PCN-PDN Information
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Support & Discussions
LTC1871-1 Discussions
Sample & Buy
Ordering FAQs
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Buy Now Pricing
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List Pricing
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Lead Times
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Sampling
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Evaluation Boards
Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.