UM202EESE High ESD-Protected, Fail-Safe, Single Supply RS-232 Transceivers

Overview

Union's UM202EESE is a high-performance RS-232 transceiver that integrates two drivers and two receivers, supporting full-duplex communication and operating from a single 5V supply. It is designed for robust and cost-effective serial communication in industrial, consumer, and embedded systems. The TRS202EID from Texas Instruments is a similar dual-channel RS-232 device. However, Union’s UM202EESE offers several competitive advantages in terms of power consumption, signal integrity, protection robustness, and integration simplicity.

Electrical Performance and Data Rate

The UM202EESE supports data transmission rates up to 250 kbps, with controlled slew rate to reduce electromagnetic interference (EMI), ensuring reliable communication over long cables. This makes it suitable for legacy systems as well as industrial or embedded applications that require RS-232 interface compliance.

Similarly, the TRS202EID supports up to 250 kbps with slew rate limiting. However, the UM202EESE maintains signal integrity more effectively under capacitive load conditions, thanks to its carefully optimized driver output characteristics and receiver input thresholds.

ESD Protection and Reliability

A standout advantage of the UM202EESE is its ±15kV ESD protection on RS-232 pins, compliant with IEC 61000-4-2 standards (both contact and air discharge). This robust level of protection ensures higher system reliability, especially in industrial, consumer, and portable applications where electrostatic discharges are common.

In contrast, the TRS202EID typically offers ±2kV HBM ESD protection, which is sufficient for general-purpose use but significantly lower than Union's solution. As a result, the UM202EESE reduces the need for external TVS diodes or clamping devices, thereby saving board space and cost.

Power Consumption and Efficiency

The UM202EESE operates from a single 5V supply and features low quiescent current consumption, with automatic power-down when no valid signal is present. This greatly benefits battery-powered and energy-sensitive applications, such as handheld devices and low-power embedded systems.

While TRS202EID also operates from 5V, it exhibits higher static and dynamic power consumption, and lacks a smart auto-power-down function. Union’s power-efficient design in UM202EESE offers improved energy management and longer battery life, especially in systems with idle-time operation.

External Component Requirements

The UM202EESE integrates an on-chip charge pump, requiring only four external 0.1 µF capacitors for operation—enabling compact PCB designs. This simplifies implementation while ensuring stable RS-232 voltage levels (typically ±5.5V output swings) from a single 5V source.

In comparison, TRS202EID often requires larger 1 µF capacitors for the same function, which can occupy more board space and potentially increase BOM costs. The UM202EESE’s compatibility with smaller capacitors provides greater design flexibility for space-constrained applications.

Packaging and Thermal Considerations

Union offers the UM202EESE in an industry-standard SOIC-16 package, ensuring compatibility with standard PCB layouts and automated assembly processes. It is designed to operate reliably across a wide industrial temperature range (-40°C to +85°C), with stable thermal characteristics even under continuous operation.

The TRS202EID also comes in an SOIC-16 package with a similar temperature range. However, due to lower power consumption and improved thermal efficiency, UM202EESE is better suited for densely populated boards or thermally stressed environments.

Cost and Supply Chain Advantage

Union’s UM202EESE is cost-effective and readily available, with strong manufacturing support and short lead times, making it suitable for large-volume production. It also provides competitive pricing without sacrificing performance or reliability.

In contrast, TRS202EID may be subject to global supply fluctuations and longer lead times, which can delay project schedules. Union’s local manufacturing presence and supply chain responsiveness offer a strategic sourcing advantage to customers seeking stable procurement and shorter time-to-market.

Conclusion

Union’s UM202EESE RS-232 transceiver delivers clear advantages over TI’s TRS202EID, particularly in:

• Higher ESD protection (±15kV IEC vs. ±2kV HBM)

• Lower power consumption with auto power-down

• Smaller external capacitors (0.1 µF vs. 1 µF)

• Improved signal integrity under load

• Cost-efficiency and shorter lead times

For designers looking to optimize reliability, size, and cost in RS-232-based applications, the UM202EESE provides a superior solution with proven industrial-grade performance.