MAX3218CAP+

Overview

The MAX3218CAP+ is a dual-driver, dual-receiver RS-232 transceiver designed for battery-powered EIA/TIA-232E and V.28/V.24 interfaces. It operates from a single supply voltage ranging from +1.8V to +4.25V, enabling direct connection to two alkaline, NiCd, or NiMH cells without external regulators. The device guarantees a data rate of 120kbps while maintaining true RS-232 and EIA/TIA-562 voltage levels. It incorporates an AutoShutdown feature that reduces supply current to 1µA when no valid signal is detected on the receiver inputs. The component is housed in a 20-pin SSOP package and supports an operating temperature range of 0°C to +70°C.

Feature Summary

• AutoShutdown technology minimizes power consumption by disabling the onboard power supply and drivers when valid RS-232 signals are absent.
• Integrated switch-mode power supply generates required internal voltages using minimal external components, including a single inductor.
• Three-state receiver outputs allow multiple receivers with different interface standards to share the same bus.
• Operates directly from low-voltage battery sources without requiring additional voltage regulation circuitry.

Applications

• Battery-powered portable equipment
• Subnotebook computers
• Personal Digital Assistants (PDAs)
• Hand-held devices and peripherals
• Cellular phones

Procurement Notes

Verify the specific suffix CAP+ corresponds to the 20-pin SSOP package and commercial temperature range (0°C to +70°C). Confirm RoHS compliance status as indicated by the plus sign in the part number. Ensure the ordering documentation matches the manufacturer's official lead-free specifications before finalizing procurement.

Selection Notes

Select this component for designs requiring low-power RS-232 communication powered by two series battery cells. The integrated boost converter eliminates the need for separate charge pump circuits. Consider the 120kbps data rate limit and ensure the application does not require higher baud rates. Verify that the external inductor meets the specified saturation current requirements for reliable operation.

Part Context

The MAX3218 belongs to the Maxim Integrated RS-232 transceiver family, specifically engineered for ultra-low power applications. It serves as a successor to standard bipolar RS-232 drivers by integrating CMOS logic with a switch-mode power supply. This architecture allows for significant size reduction in portable electronics compared to traditional solutions requiring larger capacitors and higher supply voltages.

Replacement Considerations

MAX3218CPP+