MAX6818EAP+TG52

Specialized ICS Overview

The MAX6818EAP+TG52 is an octal CMOS switch debouncer designed for robust mechanical switch interfacing in harsh environments. It accepts bouncing inputs and produces clean digital outputs after a preset qualification delay, removing both opening and closing bounce. The device operates on a single supply from +2.7V to +5.5V with undervoltage lockout ensuring correct power-up states. Key electrical parameters include a typical debounce duration of 40ms, a supply current of 6µA at VCC=5V, and input thresholds of 0.8V (VIL) and 2.4V (VIH at VCC=5V). It features ±15kV ESD protection and handles ±25V input levels.

Specialized ICS Feature Summary

• Octal configuration with three-state outputs controlled by an active-low enable pin.
• Provides a change-of-state output (CH) to simplify microprocessor polling and interrupts.
• Robust inputs tolerate ±25V levels and offer ±15kV ESD protection per IEC 1000-4-2 standards.
• Pin-compatible with the LS573 octal latch (excluding the CH pin) for direct data bus interfacing.

Specialized ICS Applications

• Microprocessor switch interfacing
• Industrial instruments
• PC-based instruments
• Portable instruments
• Membrane keypads

Specialized ICS Procurement Notes

Verify that the specific ordering suffix TG52 corresponds to the Tape & Reel packaging format as indicated in local product fields. Confirm RoHS compliance status associated with the '+' designation in the part number. Ensure the procurement channel provides valid traceability documentation for this Analog Devices/Maxim Integrated component.

Specialized ICS Selection Notes

Select the MAX6818 when eight independent switch channels are required with direct data bus connectivity. The three-state outputs allow sharing a microprocessor bus without external tri-state buffers. This model is suitable for applications requiring high ESD immunity and fault tolerance against overvoltage conditions up to ±25V on the input lines.

Specialized ICS Part Context

The MAX6818 is part of the MAX6816/MAX6817/MAX6818 family of CMOS switch debouncers. While the MAX6816 offers a single channel and the MAX6817 provides dual channels in small SOT packages, the MAX6818 delivers octal functionality in a 20-pin SSOP package. This family eliminates the need for external components or software-based debouncing logic.

Specialized ICS Replacement Considerations

Direct pin-compatible replacements within the same family include the MAX6818EAP (non-RoHS version). For single-channel needs, the MAX6816EUS-T is available in a SOT143 package. For dual-channel requirements, the MAX6817EUT-T in a SOT23-6 package serves as a functional alternative with reduced channel count.

Specialized ICS FAQ

How does the MAX6818 handle switch state changes?

The MAX6818 monitors all eight inputs and generates a low signal on the Change-of-State (CH) output after the debounce period (typically 40ms) if any input changes state. This allows the microprocessor to poll only when necessary.

What is the function of the EN pin?

The Enable (EN) pin controls the three-state outputs. When EN is low, the outputs are active. When EN is high, the outputs enter a high-impedance state. Pulling EN low also resets the CH output.

Can the inputs withstand voltages higher than the supply voltage?

Yes, the switch inputs can safely swing to ±25V relative to ground, even if the supply voltage is lower. This feature protects the device in harsh industrial environments where fault conditions may occur.