MAX248CQH-D

Overview

The MAX248CQH-D is a +5V-powered, multichannel RS-232 transceiver featuring eight drivers and eight receivers. It operates in full-duplex mode with a data rate of 120 kb/s. The device utilizes an integrated charge pump to generate internal ±10V rails from a single +5V supply, eliminating the need for external bipolar power sources. It is housed in a PLCC-44 package and supports surface-mount installation. The unit functions within a temperature range of -40°C to +85°C, drawing 30 mA during operation.

Feature Summary

• Integrates dual charge-pump circuitry to convert a single +5V input into the required internal voltage levels for RS-232 signaling.
• Provides eight independent driver and receiver channels for high-density multidrop network applications.
• Includes dedicated control inputs to manage transmitter and receiver states independently.

Applications

• Multidrop RS-232 networks
• Interface translation between TTL/CMOS logic and RS-232 standards
• Portable diagnostics equipment

Procurement Notes

Verify the specific suffix 'D' against the manufacturer's current ordering guide to confirm the exact package variant and lead-free status. Ensure the component meets the required industrial temperature specifications for the target deployment environment before finalizing the bill of materials.

Selection Notes

Select this component when a design requires multiple serial communication channels without the board space penalty of discrete level shifters. Confirm that the system can accommodate the necessary external capacitors for the charge pump circuitry, as these are not integrated internally unlike other members of the MAX220-MAX249 family.

Part Context

This part belongs to the MAX220–MAX249 family of line drivers and receivers designed for EIA/TIA-232E and V.28/V.24 interfaces. The family offers various channel counts and package options to suit different density requirements while maintaining compatibility with standard single-supply operations.

Replacement Considerations

Direct substitutes within the same family include the MAX247 and MAX249, which offer similar multichannel capabilities. Verify pinout compatibility and control logic configurations when swapping between these variants to ensure proper interface translation functionality.

FAQ

Does the MAX248CQH-D have integrated capacitors?

No, the MAX248 requires external capacitors for its charge pump circuitry. Integrated capacitors are only found in specific models such as the MAX223, MAX233, MAX235, and MAX245 through MAX247.

What is the maximum data rate supported by this device?

The MAX248 supports a maximum data rate of 120 kb/s under normal operating conditions.

How does the shutdown feature affect the internal voltage rails?

When the shutdown feature is activated, the internal voltage rails change state; specifically, V- falls to 0V and V+ falls to +5V, reducing power consumption significantly.