MAX3320ACAP+

Overview

The MAX3320ACAP+ is a true RS-232 transceiver integrated with a microprocessor power-on reset circuit, manufactured by Analog Devices Inc./Maxim Integrated. It operates on a single +3V to +5.5V supply and supports data rates up to 250kbps. The device includes two drivers and two receivers within a 20-pin SSOP package. It features AutoShutdown Plus technology, reducing supply current to 4µA during inactivity. The integrated power-on reset provides a minimum 100ms pulse width and remains valid down to VCC = 1V.

Feature Summary

• Integrates a dual charge pump for generating RS-232 voltage levels from a low-voltage single supply
• Includes an active-low RESET output that monitors the VCC supply voltage against a preset threshold
• Features AutoShutdown Plus logic to automatically enter a low-power state when serial lines are idle
• Provides an INVALID output signal to indicate the absence of valid RS-232 signaling levels

Applications

• Palmtop Computers
• Portable/Battery-Powered Equipment
• Hand-Held Equipment
• Peripherals
• Printers

Procurement Notes

Verify the specific reset threshold voltage required for the application before procurement. The 'A' suffix indicates a 4.25V reset threshold; other thresholds require different ordering suffixes. Confirm the operating temperature range matches the design requirements, as the CAP variant is rated for commercial temperatures. Ensure the component meets RoHS compliance standards if mandated by the project specifications.

Selection Notes

Select this component when a combined RS-232 interface and system supervision function is needed to save board space. The choice of the 'A' suffix depends on whether the 4.25V reset threshold aligns with the target system's power rail stability. Consider the 4µA shutdown current for battery-operated designs requiring extended standby times. Verify that the 250kbps maximum data rate satisfies the communication speed requirements of the connected peripherals.

Part Context

This part belongs to the MAX3320A/B/L/T family of RS-232 transceivers. The family shares identical electrical characteristics and pinouts but differs in the internal reset comparator threshold voltage. The MAX3320ACAP+ specifically denotes the version with a 4.25V reset threshold housed in a commercial temperature range SSOP-20 package.

Replacement Considerations

Direct substitutes within the same family include MAX3320BCAP+, MAX3320LCAP+, and MAX3320TCAP+, which offer different reset thresholds. Other Maxim RS-232 transceivers may serve as functional replacements if the reset feature is not required or can be implemented externally.