DS4550E+

Overview

The DS4550E+ is a nonvolatile I/O expander featuring nine bidirectional inputs and outputs housed in a 20-pin TSSOP package. It integrates 64 bytes of EEPROM user memory accessible via an I2C-compatible serial interface or a JTAG port. The device operates within a supply voltage range of 2.7V to 5.5V and supports SCL clock frequencies up to 400kHz. Each output provides open-drain capability with selectable internal pullup resistors, capable of sinking 16mA. The unit functions across an operating temperature range of -40°C to +85°C.

Feature Summary

• Digitally programmable replacement for mechanical jumpers and switches
• Dual access interfaces including I2C serial bus and JTAG port
• Nonvolatile memory retains configuration states during power loss
• Outputs feature configurable pullups and high current sinking capability

Applications

• RAM-Based FPGA Bank Switching for Multiple Profiles
• Selecting Between Boot Flash
• Setting ASIC Configurations/Profiles
• Servers and Network Storage Systems
• Routers and Telecom Equipment

Procurement Notes

Verify the specific ordering suffix when purchasing components. The standard tube packaging corresponds to the base part number, while tape and reel orders require adding the /T&R suffix to the manufacturer part number. Confirm RoHS compliance status and ensure the selected variant matches the required pin-package configuration for the target application design.

Selection Notes

Evaluate the system requirements against the available I2C address options determined by the A0, A1, and A2 pins. Consider the SRAM-shadowed EEPROM mode if frequent register updates are necessary to preserve memory endurance. Ensure the host controller supports either the I2C protocol or JTAG boundary scan instructions for proper device initialization and control.

Part Context

This component belongs to the Maxim Integrated DS4550 series of nonvolatile I/O expanders. It serves as a digital alternative to hardware jumpers, allowing dynamic configuration of logic nodes without physical intervention. The device is designed for systems requiring persistent state retention and flexible interface control through standard communication protocols.

Replacement Considerations

Direct substitutes include the DS4550E and DS4550E+ variants. Verify that any replacement maintains compatibility with the existing I2C addressing scheme and JTAG instruction set. Ensure the pinout remains identical to avoid PCB redesign when swapping between different manufacturing lots or suffixes.