LTC6820HMS#TRPBF

Specialized Overview

The LTC6820HMS#TRPBF is an isoSPI isolated communications interface IC manufactured by Analog Devices Inc. It provides bidirectional SPI communication between two isolated devices through a single twisted-pair connection, bridging the isolation barrier with a simple pulse transformer. The device operates on a VDD supply range of 2.7V to 5.5V and supports logic interfaces from 1.7V to 5.5V via the VDDS pin. It achieves data rates up to 1Mb/s and supports cable lengths up to 100 meters. The component features ultralow idle current of 2µA (slave) or 1µA (master), automatic wake-up detection, and configurable drive currents for noise immunity optimization. It is housed in a 16-lead Plastic MSOP package and is qualified for automotive applications with an operating temperature range of –40°C to 125°C.

Specialized Feature Summary

• Provides galvanic isolation using standard transformers over a single twisted pair
• Translates standard SPI signals into differential pulses for robust long-distance communication
• Configurable drive currents and comparator thresholds optimize system performance for specific cable lengths and noise environments
• Supports all four standard SPI clock phase and polarity modes without software changes

Specialized Applications

• Industrial Networking
• Battery Monitoring Systems
• Remote Sensors

Specialized Procurement Notes

Verify the specific suffix #TRPBF indicates tape and reel packaging containing 2500 units. Confirm the 'H' grade designation corresponds to the extended industrial temperature range of –40°C to 125°C. Ensure the 'IMS' package code matches the required 16-lead MSOP form factor for your PCB layout constraints.

Specialized Selection Notes

Select this part when high-reliability isolated SPI communication is required over distances exceeding standard board-level limits. The adjustable bias network allows trade-offs between power consumption and signal integrity. Ensure the external transformer and termination resistors are selected to match the characteristic impedance requirements for the desired cable length.

Specialized Part Context

This component belongs to the LTC6820 family of isoSPI isolated communications interfaces. The 'H' suffix denotes the higher temperature grade variant suitable for harsh environments, while 'IMS' specifies the MSOP package. It serves as a bridge between microcontrollers and isolated slave devices, commonly used in battery management systems where safety isolation is critical.

Specialized Replacement Considerations

Public confirmed substitute part numbers: LTC6820IMS#PBF (Tube version).

Specialized FAQ

How is the isoSPI communication speed adjusted?

The communication speed is adjusted by configuring the SLOW pin. For clock frequencies at or below 200kHz, tie SLOW to VDD. For frequencies above 200kHz, tie SLOW to GND.

What determines the isolation voltage capability?

The isolation voltage is determined by the external pulse transformer used to bridge the IP and IM pins, not by the LTC6820 chip itself. The chip supports hundreds of volts of isolation depending on the transformer selection.

Can multiple slave devices be connected to one master?

Yes, the isoSPI protocol allows for multiple slave devices on a single twisted pair. Slave LTC6820 devices only transmit short pulses for data return, preventing collisions with the master's long CS pulses.