LTC1955EUH#TRPBF

Specialized Overview

The LTC1955EUH#TRPBF is a dual smart card interface IC with serial control, designed to manage power and supervisory functions for two smart cards or S.A.M. modules. It features an integrated buck/boost charge pump generating 5V, 3V, or 1.8V outputs compatible with ISO7816-3 and EMV standards. The device operates from a VBATT supply of 2.7V to 5.5V with a typical operating current of 250µA and shutdown current of 0.75µA. Communication occurs via a 4-wire serial interface supporting daisy-chaining up to 10MHz. It includes automatic debounce, level translation, and fault protection, housed in a 32-lead 5mm × 5mm QFN package.

Specialized Feature Summary

• Integrated buck/boost charge pump generates independent 5V, 3V, or 1.8V supplies for dual smart card channels.
• Serial port supports daisy-chaining multiple devices for multicard applications with status polling.
• Automatic deactivation sequencing prevents electrical faults and ensures secure shutdown during supply anomalies.
• Built-in card detection with automatic debounce and dynamic pull-up current sources for bidirectional I/O.

Specialized Applications

• Handheld payment terminals
• ATM machines
• POS terminals
• Pay telephones

Specialized Procurement Notes

Verify the specific suffix #TRPBF indicates tape and reel packaging when sourcing. Confirm the EUH grade meets the required -40°C to 85°C operating temperature range for your application environment. Ensure the 32-lead QFN footprint matches your PCB layout constraints before finalizing procurement orders.

Specialized Selection Notes

Select this component when managing dual smart card interfaces with limited microcontroller pins. The serial control reduces wiring complexity compared to parallel interfaces. Verify that the input voltage range of 2.7V to 5.5V aligns with your system battery or supply architecture. Consider the 250µA typical operating current if power efficiency is critical for battery-powered designs.

Specialized Part Context

This part belongs to the LTC1955 series of smart card interface controllers manufactured by Analog Devices. It provides comprehensive power management and communication control for smart card sockets. The EUH variant specifies the commercial temperature grade and lead-free finish within the standard plastic QFN package family.

Specialized Replacement Considerations

Consult official documentation for direct substitutes. No public confirmed substitute part numbers are available in the provided source material.