DS4550E+T&R

Overview

The DS4550E+T&R is a nonvolatile I/O expander featuring nine bidirectional I/O pins and 64 bytes of EEPROM user memory. It supports I2C-compatible serial and JTAG interfaces for control. The device operates within a supply voltage range of 2.7V to 5.5V and functions across temperatures from -40°C to +85°C. Outputs are open-drain with selectable pullups, capable of sinking up to 16mA. The maximum SCL clock frequency is 400kHz. It is housed in a 20-pin TSSOP package.

Feature Summary

• Digitally programmable replacement for hardware jumpers and mechanical switches
• Nonvolatile I/O pins maintain state after power loss without host CPU intervention
• Dual interface access via I2C serial bus or standard JTAG port
• Configurable internal pullup resistors on all I/O pins

Applications

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

Procurement Notes

Verify the specific ordering suffix against manufacturer documentation to confirm tape and reel packaging requirements. Ensure the component meets RoHS standards and confirm availability status through authorized distributors prior to finalizing procurement plans.

Selection Notes

Confirm that the system logic levels align with the specified input voltage thresholds. Verify that the required number of address pins allows for sufficient device multiplexing on the I2C bus. Check if the JTAG boundary scan capabilities are necessary for the design.

Part Context

This component belongs to the DS4550 series manufactured by Analog Devices Inc./Maxim Integrated. It serves as a specialized interface IC designed to replace physical configuration hardware with digitally controlled alternatives.

Replacement Considerations

DS4550E+

FAQ

How does the device handle power-up states?

The device powers up in its desired nonvolatile state immediately, allowing it to control digital logic inputs without waiting for the host CPU to initiate control.

Can both I2C and JTAG interfaces be used simultaneously?

No, the device contains no bus arbitration mechanism, so both busses cannot be used at the same time.

What is the function of the SEE bit in the Configuration Register?

When set to 1, the SEE bit disables writes to the EEPROM, directing data only to shadow SRAM to eliminate write times and prevent EEPROM wear.