Black Box RS-232 to 5V TTL Bidirectional Converter DB9

Overview

The Black Box IC1157A is a bidirectional converter designed to bridge RS-232 equipment with devices that use 5 V TTL logic levels. It automatically shifts voltage levels on both transmit and receive lines, enabling seamless communication between these two interfaces. Supporting serial data rates up to 115 kbps, it ensures responsive control and monitoring for applications involving sensors, relays, or microcontrollers without requiring an external power supply.

Key features

• Converts RS-232 signals to 5 V TTL and back on two independent channels, allowing full duplex communication for command-and-response or continuous data streaming
• Draws power directly from the RS-232 port, eliminating the need for additional power adapters and simplifying installation
• Compact housing designed to fit easily inside control cabinets or portable service kits, saving space in tight environments
• Plug-and-play operation with no jumpers, firmware, or special drivers required, making setup quick and straightforward
• Reliable performance at data rates up to 115 kbps, suitable for field service, prototyping, and permanent installations

Key specs

• Data rate: up to 115 kbps
• Voltage levels: RS-232 to 5 V TTL bidirectional conversion
• Connector type: DB9 male for RS-232 interface
• Power source: powered directly from RS-232 port
• Channels: two independent channels for transmit and receive

Installation and setup

Installation involves plugging the DB9 male connector into the RS-232 port and wiring the TTL side to the target device. The converter requires no configuration, jumpers, or drivers, allowing you to set your software to the desired baud rate and start communicating immediately. This simplicity makes it ideal for technicians working in the field, developers prototyping embedded systems, and system integrators managing compact control panels.

Ideal uses and environments

The IC1157A is well suited for industrial environments where legacy RS-232 equipment must interface with modern TTL-based devices. It fits naturally into field service toolkits for troubleshooting and maintenance of older machinery. Developers benefit from its straightforward connection when testing embedded prototypes, while system integrators appreciate its compact size for space-constrained control cabinets. Its ability to handle full duplex communication at practical data rates makes it a strong choice for applications requiring reliable, real-time data exchange.