MAX3225CUP+

Overview

The MAX3225CUP+ 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 data rates up to 1Mbps (MegaBaud) and includes an internal dual charge pump requiring only four small capacitors for voltage conversion. It features a 20-pin TSSOP package with an operating temperature range of 0°C to +70°C.

Feature Summary

• AutoShutdown Plus functionality automatically reduces power consumption when the interface is idle or disconnected.
• MegaBaud operation ensures reliable high-speed communication at data rates up to 1Mbps.
• Integrated dual charge pump generates required RS-232 voltages using minimal external components.
• READY output pin indicates when the internal charge pumps are regulating and the device is ready for transmission.

Applications

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

Procurement Notes

Verify the specific suffix 'CUP+' against the manufacturer's official ordering guide to confirm the 20-pin TSSOP package and commercial temperature range. Ensure compatibility with existing BIOS configurations if relying on automatic shutdown features without software modification.

Selection Notes

Select this component for applications requiring low-power standby modes in battery-operated systems. Compare against MAX3226 variants if a lower 250kbps data rate is sufficient, or consider E-grade parts for extended industrial temperature ranges.

Part Context

This part belongs to the MAX3224–MAX3227 series of true RS-232 transceivers designed for 3V systems. It shares architectural similarities with the MAX3244/MAX3245 but lacks the three-state receiver outputs and complementary R2OUTB pin found in those specific models.

Replacement Considerations

MAX3225CAP+

FAQ

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

The device enters shutdown mode when valid signal transitions are not detected on any receiver or transmitter input for more than 30 seconds, such as when the cable is disconnected or peripherals are inactive.

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 reached stable operating conditions, indicating it is ready to begin transmitting.