ADI AD231AN

The AD230 family of 5 V only, RS - 232 line drivers/receivers provides a variety of configurations to fit most communication needs, especially in applications where ±12 V is not available. The AD230, AD235, AD236 and AD241 feature a low power shutdown mode which reduces power dissipation to less than 5 μW, making them ideally suited for battery powered equipment. The AD233 and AD235 do not require any external components and are particularly useful in applications where printed circuit board space is critical.

All members of the AD230 family, except the AD231 and the AD239, include two internal charge pump voltage converters which allow operation from a single +5 V supply. These converters convert the +5 V input power to the ±10 V required for RS - 232 output levels. The AD231 and AD239 are designed to operate from +5 V and +12 V supplies. An internal +12 V to - 12 V charge pump voltage converter generates the - 12 V supply.

The AD230 - AD241 family of RS - 232 drivers/receivers are designed to solve interface problems by meeting the RS - 232 - C specifications while using a single digital +5 V supply. The RS232 - C standard requires transmitters which will deliver ±5 V minimum on the transmission channel and receivers which can accept signal levels down to ±3 V. The AD230 - AD241 meet these requirements by integrating step up voltage converters and level shifting transmitters and receivers onto the same chip. CMOS technology is used to keep the power dissipation to an absolute minimum. A comprehensive range of transmitter/receiver combinations is available to cover most communications needs.

The AD230, AD235, AD236 and AD241 are particularly useful in battery powered systems as they feature a low power shutdown mode which reduces power dissipation to less than 5 μW.

The AD233 and AD235 are designed for applications where space saving is important as the charge pump capacitors are molded into the package.

The AD231 and AD239 include only a negative charge pump converter and are intended for applications where a positive 12 V is available.

To facilitate sharing a common line or for connection to a microprocessor data bus the AD235, AD236, AD239 and AD241 feature an enable (EN) function. When disabled, the receiver outputs are placed in a high impedance state.

The internal circuitry in the AD230 - AD241 consists of three main sections. These are: (a) A charge pump voltage converter (b) RS - 232 to TTL/CMOS receivers (c) TTL/CMOS to RS - 232 transmitters

• Single 5 V Power Supply
• Meets All RS - 232 - C and V.28 Specifications
• Multiple Drivers and Receivers
• On - Board DC - DC Converters
• ±9 V Output Swing with +5 V Supply
• Low Power CMOS: 5 mA Operation
• Low Power Shutdown ≤1 μA
• 3 - State TTL/CMOS Receiver Outputs
• ±30 V Receiver Input Levels
• Plug - in Replacement for MAX230 - 241

• Computers
• Peripherals
• Modems
• Printers
• Instruments