DS275S

Overview

The DS275S is a line-powered RS-232 transceiver in an 8-pin SOIC package. It operates with a logic supply (VCC) of 4.5V to 5.5V and a driver supply (VDRV) of 4.5V to 13.0V. The device features one receiver and one transmitter, supporting half-duplex communication at speeds up to 20kbps. Static current consumption is typically 10µA when VCC is active and the RXIN line is marking. Dynamic current ranges from 40µA to 800µA depending on the TXIN state. The operating temperature range is 0°C to +70°C.

Feature Summary

• Steals power from the receive signal line during negative states to minimize static current drain
• Translates RS-232 signal levels directly to CMOS/TTL logic levels without external charge pumps
• Variable transmitter output level adjustable from +5V to +12V via the VDRV pin

Applications

• Battery-backed laptop computers
• Remote sensors
• Portable medical instruments

Procurement Notes

Verify component authenticity through authorized distributors or direct manufacturer channels. Confirm RoHS compliance status as indicated in official documentation. Check for obsolescence notices regarding the DS275 series. Ensure the specific suffix matches the required package type. Review datasheet revisions for any updates to electrical characteristics.

Selection Notes

Select this component for applications requiring ultra-low static power consumption in battery-operated systems. Ensure the VDRV supply voltage meets the requirement of being greater than or equal to VCC. Verify that the cable length remains under 10 feet to maintain signal integrity. Consider full-duplex circuit modifications if simultaneous transmission and reception are required.

Part Context

The DS275S belongs to the DS275 family of low-power RS-232 transceivers manufactured by Analog Devices / Maxim Integrated. This family includes variants such as the DS275SN and DS275E. The device is designed specifically for serial port interfaces where power conservation is critical.

Replacement Considerations

DS275SN

FAQ

How does the DS275S reduce static power consumption?

It steals current from the receive RS-232 signal line when that signal is in a negative state (marking), which is the typical idle state for most serial ports.

What is the relationship between VDRV and VCC?

The VDRV supply voltage must be greater than or equal to the VCC logic supply voltage at all times for proper operation.

Can the DS275S operate in full-duplex mode?

Yes, it can operate in full-duplex mode with most RS-232-E ports, though a modified circuit using a negative-charge reservoir capacitor may be needed for optimal performance.