Features and Benefits
- Allows Safe Insertion into Live –48V Backplanes
- 10-Bit ADC Monitors Current and Voltages
- I2C/SMBus Interface or Single-Wire Broadcast Mode
- Floating Topology Allows Very High Voltage Operation
- Independently Adjustable Inrush and Overcurrent Limits
- Controlled Soft-Start Inrush
- Adjustable UV/OV Thresholds and Hysteresis
- Sequenced Power Good Outputs with Delays
- Adjustable Power Good Input Timeout
- Programmable Latchoff or Auto-Retry After Faults
- Alerts Host After Faults
- Available in 28-Lead Narrow SSOP and 24-Lead (4mm × 5mm) QFN Packages
The LTC4261/LTC4261-2 negative voltage Hot Swap™ controllers allow a board to be safely inserted and removed from a live backplane. Using an external N-channel pass transistor, the board supply voltage can be ramped at an adjustable rate. The devices feature independently adjustable inrush current and overcurrent limits to minimize stresses on the pass transistor during start-up, input step and output short conditions. The LTC4261 defaults to latch-off while the LTC4261-2 defaults to auto-retry on overcurrent faults.
An I2C interface and onboard 10-bit ADC allow monitoring of board current, voltage and fault status. A single-wire broadcast mode is available to simplify the interface by eliminating two optoisolators.
The controllers have additional features to interrupt the host when a fault has occurred, notify when output power is good, detect insertion of a board and turn off the pass transistor if an external supply monitor fails to indicate power good within a timeout period.
- AdvancedTCA Systems
- Telecom Infrastructure
- –48V Distributed Power Systems
- Power Monitors
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.
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.
Models for the following parts are available in LTspice:
Design Notes (1)
Technical Articles (1)
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.