MAX3225EEAP+T

Overview

The MAX3225EEAP+T is a dual driver/receiver RS-232 transceiver from the MAX3224–MAX3227 family, manufactured by Analog Devices Inc./Maxim Integrated. It operates on a single +3.0V to +5.5V supply and achieves a typical supply current of 1µA through AutoShutdown Plus technology. The device guarantees a data rate of 1Mbps (MegaBaud) for high-speed applications. It features a dual charge pump requiring only four small capacitors for operation. The component is housed in a 20-pin SSOP package and supports an operating temperature range of -40°C to +85°C.

Feature Summary

• AutoShutdown Plus functionality automatically reduces power consumption when the interface is idle or disconnected.
• MegaBaud capability ensures reliable communication at speeds up to 1Mbps.
• Integrated dual charge pump generates required voltage levels using minimal external components.
• Logic-level READY output indicates when the internal charge pumps are regulating and the device is ready.

Applications

• Notebook, subnotebook, and palmtop computers
• Cellular phones and handheld equipment
• Battery-powered peripherals and printers

Procurement Notes

Verify the specific ordering suffix against official documentation to confirm package type and temperature rating. Confirm RoHS compliance status as indicated by the '+' designation. Ensure compatibility with existing BIOS or operating system configurations if utilizing automatic shutdown features without modification.

Selection Notes

Select this model for designs requiring true RS-232 performance from low-voltage supplies. The MAX3225 variant is appropriate where 1Mbps data rates are necessary, distinguishing it from the 250kbps MAX3224/MAX3226 counterparts. Consider the 20-pin SSOP footprint for space-constrained surface-mount layouts.

Part Context

This component belongs to the MAX3224–MAX3227 series of EIA/TIA-232 and V.28/V.24 communications interfaces. The family shares common features such as AutoShutdown Plus and dual charge pumps, with variations primarily defined by guaranteed data rates and the number of drivers/receivers.

Replacement Considerations

Publicly confirmed substitutes within the same datasheet include the MAX3224EAP+, MAX3226EAP+, and MAX3227EAP+. Note that these alternatives offer different data rate guarantees (250kbps for MAX3224/MAX3226) or pin counts (single driver/receiver for MAX3227).

FAQ

How does the AutoShutdown Plus feature function?

The device enters a low-power shutdown mode when the RS-232 cable is disconnected or all transmitter/receiver inputs remain inactive for more than 30 seconds. It wakes up upon sensing a valid transition at any input.

What is the purpose of the READY output pin?

The READY output asserts high when the internal charge pumps are regulating and the device has reached sufficient voltage levels to begin transmitting reliably.

What capacitor values are required for 3.3V operation?

For a 3.3V supply, the datasheet specifies using 0.1µF capacitors for C1 through C4 to support the dual charge pump operation.