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
- ±2% Internal Voltage Reference
- Micropower Shutdown: IQ = 10μA
- Programmable Operating Frequency (65kHz to 900kHz) 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
LTC1871X is a wide input range, current mode, boost, flyback or SEPIC controller that drives an N-channel power MOSFET. LTC1871X is rated to 175°C junction temperature and is 100% tested at 175°C. Intended for low to medium power applications, it eliminates the need for a current sense resistor by utilizing the power MOSFET’s on-resistance, thereby maximizing efficiency.
The IC’s operating frequency can be set with an external resistor over a 65kHz to 900kHz range, and can be synchronized to an external clock using the MODE/SYNC pin. Burst Mode operation at light loads, a low minimum operating supply voltage of 2.5V and a low shutdown quiescent current of 10μA make the LTC1871X ideally suited for battery-operated systems.
For applications requiring constant frequency operation, Burst Mode operation can be defeated using the MODE/SYNC pin. Higher output voltage boost, SEPIC and flyback applications are possible with the LTC1871X by connecting the SENSE pin to a resistor in the source of the power MOSFET. The LTC1871X is available in the 10-lead MSOP package.
|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|
- 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.
Tools & Simulations
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.
Models for the following parts are available in LTspice:
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.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.