Overview
The ADM238LJN is a 5 V-powered CMOS RS-232 driver/receiver integrated circuit produced by Analog Devices Inc. This device is part of the ADM2xx family, designed to meet the requirements of EIA-232-E and V.28 communications interfaces. It is particularly useful in applications where a single 5 V supply is available and 12 V is not necessary. The ADM238LJN features on-board DC-DC converters that generate the ±10 V required for RS-232 output from a single 5 V supply, making it suitable for a wide range of communication needs.
Key Specifications
| Parameter | Value |
|---|---|
| Supply Voltage | 5 V |
| Data Rate | Up to 120 kB/s |
| RS-232 Output Swing | ±9 V with 5 V supply |
| Input Logic Threshold Low | 0.8 V |
| Input Logic Threshold High | 2.0 V |
| RS-232 Input Voltage Range | –30 V to +30 V |
| RS-232 Input Threshold Low | 0.8 V to 1.2 V |
| RS-232 Input Threshold High | 1.6 V to 2.4 V |
| RS-232 Input Hysteresis | 0.65 V |
| RS-232 Input Resistance | 3 kΩ to 7 kΩ |
| TTL/CMOS Output Voltage Low | 0.4 V |
| TTL/CMOS Output Voltage High | 3.5 V |
| Shutdown Supply Current | ≤1 µA |
Key Features
- Single 5 V power supply with on-board DC-DC converters to generate ±10 V for RS-232 output.
- Low power shutdown mode reducing power dissipation to less than 5 µW.
- No external components required for the ADM233L model, making it space-efficient.
- Internal charge pump voltage converters for models other than ADM231L and ADM239L.
- Enable (EN) function to facilitate sharing a common line or connection to a microprocessor data bus.
- High impedance state for disabled receivers.
- CMOS technology for minimal power dissipation.
Applications
- Computers and peripherals.
- Modems and printers.
- Instruments and industrial equipment.
- Battery-powered systems due to low power shutdown mode.
- Applications where printed circuit board space is critical.
Q & A
- What is the primary function of the ADM238LJN?
The ADM238LJN is a 5 V-powered CMOS RS-232 driver/receiver designed for EIA-232-E and V.28 communications interfaces. - What is the supply voltage requirement for the ADM238LJN?
The ADM238LJN operates on a single 5 V supply. - What is the data rate capability of the ADM238LJN?
The ADM238LJN supports data rates up to 120 kB/s. - How does the ADM238LJN generate the required RS-232 output voltage?
The ADM238LJN uses on-board DC-DC converters to generate the ±10 V required for RS-232 output from a single 5 V supply. - What is the input voltage range for the RS-232 inputs?
The RS-232 input voltage range is –30 V to +30 V. - Does the ADM238LJN require external components?
No, the ADM238LJN does not require external components for operation, especially the ADM233L model. - What is the shutdown supply current of the ADM238LJN?
The shutdown supply current is less than 1 µA. - In what types of applications is the ADM238LJN particularly useful?
The ADM238LJN is particularly useful in battery-powered systems and applications where space is critical. - Does the ADM238LJN have an enable function?
Yes, the ADM238LJN features an enable (EN) function to facilitate sharing a common line or connection to a microprocessor data bus. - What happens to the receivers when they are disabled?
When the receivers are disabled, their outputs are placed in a high impedance state.
