Overview
The ADM232LAN, produced by Analog Devices Inc., is a 5 V-powered CMOS RS-232 driver/receiver integrated circuit. This component is designed to meet all EIA-232-E and V.28 specifications, making it suitable for various communication interfaces. The ADM232LAN operates from a single 5 V power supply and incorporates on-chip DC-DC converters to generate the necessary ±10 V for RS-232 output levels. This device is particularly useful in applications where a single power supply is available, and it supports data rates up to 120 kB/s.
Key Specifications
| Parameter | Value | Conditions |
|---|---|---|
| VCC | –0.3 V to +6 V | TA = 25°C |
| Input Logic Threshold Low (VINL) | 0.8 V | TIN, EN, SD |
| Input Logic Threshold High (VINH) | 2.0 V | TIN, EN, SD |
| Logic Pull-Up Current | 12–25 µA | |
| RS-232 Input Voltage Range | –30 V to +30 V | TIN = 0 V |
| RS-232 Input Threshold Low | 0.8–1.2 V | |
| RS-232 Input Threshold High | 1.6–2.4 V | |
| RS-232 Input Hysteresis | 0.65 V | |
| RS-232 Input Resistance | 3–5 kΩ | TA = 0°C to 85°C |
| TTL/CMOS Output Voltage Low (VOL) | 0.4 V | IOUT = –1.0 mA |
| TTL/CMOS Output Voltage High (VOH) | 3.5 V | IOUT = –1.0 mA |
| Output Enable Time (TEN) | 250 ns | CL = 150 pF |
| Output Disable Time (TDIS) | 50 ns | RL = 1 kΩ |
| Propagation Delay | 0.3 µs | RS-232 to TTL |
| Transition Region Slew Rate | 8 V/µs | RL = 3 kΩ, CL = 2500 pF |
Key Features
- Operates from a single 5 V power supply.
- Meets all EIA-232-E and V.28 specifications.
- On-chip DC-DC converters generate ±10 V for RS-232 output levels.
- Supports data rates up to 120 kB/s.
- Low power shutdown mode reduces power dissipation to less than 5 µW.
- No external components required for the ADM233L variant.
- Internal 400 kΩ pull-up resistors on TTL/CMOS inputs and 5 kΩ pull-down resistors on RS-232 inputs.
- Latch-up free operation.
Applications
- Computers and peripherals.
- Modems.
- Printers.
- Instruments.
- Battery-powered equipment due to low power shutdown mode.
Q & A
- What is the operating voltage of the ADM232LAN?
The ADM232LAN operates from a single 5 V power supply.
- What are the RS-232 input voltage ranges for the ADM232LAN?
The RS-232 input voltage range is –30 V to +30 V.
- What is the data rate supported by the ADM232LAN?
The ADM232LAN supports data rates up to 120 kB/s.
- Does the ADM232LAN require external components?
The ADM233L variant does not require any external components, but other variants may require small external capacitors for the charge pump voltage converters.
- What is the power dissipation in shutdown mode?
In low power shutdown mode, the power dissipation is reduced to less than 5 µW.
- What are the typical output voltage levels for TTL/CMOS outputs?
The TTL/CMOS output voltage levels are typically 0.4 V for low and 3.5 V for high.
- What is the propagation delay for RS-232 to TTL transition?
The propagation delay for RS-232 to TTL transition is 0.3 µs.
- Is the ADM232LAN latch-up free?
Yes, the ADM232LAN is latch-up free.
- What are the common applications of the ADM232LAN?
Common applications include computers, peripherals, modems, printers, and instruments.
- Are there any substitutes available for the ADM232LAN?
Yes, the ADM232LAN is obsolete, and substitutes like the LT1081CN#PBF are available.
