MAX3227ECAE+

Overview

The MAX3227ECAE+ is a single-driver, single-receiver RS-232 transceiver manufactured by Analog Devices/Maxim Integrated. It operates on a +3.0V to +5.5V supply and supports data rates up to 1Mbps. The device features AutoShutdown Plus technology, reducing supply current to 1μA when inputs are inactive for over 30 seconds. It includes ±15kV ESD protection on all I/O pins and utilizes a dual charge pump requiring four 0.1μF capacitors. The component is housed in a 16-pin SSOP package with an operating temperature range of 0°C to +70°C.

Feature Summary

• AutoShutdown Plus functionality automatically reduces power consumption during periods of inactivity or cable disconnection.
• Integrated dual charge pump generates internal voltage rails from a single low-voltage supply using minimal external components.
• Enhanced electrostatic discharge protection ensures robustness against high-voltage static events on transmitter and receiver lines.

Applications

• Notebook, subnotebook, and palmtop computers
• Cellular phones and battery-powered equipment
• Hand-held devices and peripherals

Procurement Notes

Verify the specific suffix 'CAE+' corresponds to the commercial temperature grade (0°C to +70°C) and SSOP-16 package configuration. Confirm RoHS compliance status as indicated by the '+' designation. Ensure the source documentation matches the exact part number to avoid confusion with extended temperature variants like the EEAE+.

Selection Notes

Select this component for applications requiring full-duplex RS-232 communication at speeds up to 1Mbps with strict power constraints. The integrated AutoShutdown Plus feature makes it suitable for battery-operated systems where minimizing quiescent current during idle states is critical. Verify that the system UART can tolerate the 30-second timeout threshold before automatic shutdown occurs.

Part Context

This device belongs to the MAX3224E through MAX3245E family of RS-232 transceivers. While sharing similar power management and ESD protection features, the MAX3227E specifically provides one driver and one receiver, distinguishing it from multi-channel counterparts like the MAX3224E or MAX3225E within the same product line.

Replacement Considerations

Direct functional replacements within the same family include the MAX3227EEAE+ for extended industrial temperature ranges (-40°C to +85°C). Other pin-compatible options may exist among Maxim's broader RS-232 portfolio, but verification of driver/receiver counts and data rate specifications is required.

FAQ

How does the AutoShutdown Plus feature determine when to enter low-power mode?

The device enters shutdown mode if no valid signal transition is detected on any receiver or transmitter input for more than 30 seconds, provided the FORCEON and FORCEOFF pins are not actively overriding the circuit.

What is the function of the READY output pin?

The READY output asserts high when the internal charge pumps are regulating and the device has generated sufficient voltage levels to begin transmitting, indicating the transceiver is ready for operation.

What external components are required for the charge pump operation?

The device requires four small capacitors, typically 0.1μF, connected to the C1+, C1-, C2+, and C2- pins to support the dual charge pump voltage conversion from the +3.0V to +5.5V supply.