TCAL6408RSVR

Overview

The TCAL6408RSVR is an 8-bit translating I2C-bus and SMBus I/O expander manufactured by Texas Instruments. It operates within a supply voltage range of 1.08V to 3.6V on both the VCCI (I2C bus) and VCCP (P-ports) sides, supporting bidirectional voltage-level translation between 1.2V, 1.8V, 2.5V, and 3.3V levels. The device features a maximum clock frequency of 1MHz for fast-mode-plus operation and includes an active-low reset input alongside an open-drain active-low interrupt output. It is housed in a UQFN-16 package with dimensions of 2.6mm x 1.8mm.

Feature Summary

• Bidirectional voltage-level translation capability between varying I2C bus and P-port power supplies
• Agile I/O configuration registers enabling programmable drive strength, pull-up/pull-down resistors, and latchable inputs
• Hardware address pin support allowing two devices to operate on the same I2C or SMBus bus
• High ESD protection performance exceeding JESD 22 standards with latched-up resistance over 100mA

Applications

• Servers
• Routers and telecom switching equipment
• Personal computers
• Products with GPIO-limited processors

Procurement Notes

Verify the specific suffix RSV corresponds to the UQFN-16 package variant when sourcing components. Confirm that the operating environment remains within the specified -40°C to +125°C temperature range to ensure functional reliability. Ensure external pull-up resistors are correctly terminated at VCCI or VCCP according to the system design requirements.

Selection Notes

Select this component when interfacing low-voltage processors with higher-voltage peripherals requiring GPIO expansion. The dual-supply architecture allows independent power domains for the I2C controller and peripheral ports. Consider the Agile I/O features if noise reduction via programmable drive strength or internal pull-up/down configurations is required for the specific application layout.

Part Context

The TCAL6408 belongs to the TCAL64xx family of translating I/O expanders designed for I2C and SMBus protocols. This series addresses the need for voltage translation and port expansion in systems where processor GPIOs are insufficient. The RS designation specifically identifies the UQFN package form factor used in space-constrained designs.

Replacement Considerations

TCAL6408IDTBR

FAQ

How does the TCAL6408 handle voltage translation?

The device uses separate supply pins, VCCI for the I2C bus side and VCCP for the P-ports, allowing it to translate signals bidirectionally between different voltage levels ranging from 1.08V to 3.6V.

What is the function of the ADDR pin?

The ADDR pin serves as a hardware address input that allows two TCAL6408 devices to be connected to the same I2C or SMBus bus simultaneously by selecting one of two possible device addresses.

Can the TCAL6408 directly drive LEDs?

Yes, the P-ports configured as outputs can sink up to 25mA to directly drive LEDs, provided that the current is externally limited with additional resistance to prevent damage.