High-Voltage Amplifiers Target Error-Sensitive Applications

Texas Instruments (TI) has introduced three new amplifiers that offer a combination of high speed and high precision, allowing designers to create more accurate circuits for error-sensitive applications.  With maximum supply voltages ranging from 27 V to 36 V, the new devices support more precise measurement and faster processing of a wide variety of input signals in test and measurement, medical, and data-acquisition systems.

Designers can select the amplifier architecture that meets their system requirements, with input voltages, bandwidths and key features. The OPA2810 is a 27-V junction gate field-effect transistor (JFET)-input dual operational amplifier (op amp) with 120-MHz bandwidth and 500-µV max offset voltage. The OPA189 is a 36-V zero-drift op amp with 14-MHz bandwidth and is multiplexer (MUX) friendly. And finally, the THS3491 is a 32-V current-feedback amplifier with
900-MHz small-signal bandwidth and ±420-mA output current.

The high bandwidths of the OPA2810 and OPA189 enable high-gain configurations and faster response times for more accurate measurements. Designers can use the THS3491 current-feedback amplifier’s wide small-signal bandwidth, high slew rate and output current of ±420 mA to achieve low distortion and high output power levels. The THS3491 is capable of 10-Vpeak-to-peak output levels at 200 MHz into 100-Ω loads for test and measurement systems, such as arbitrary waveform generators, laser diode drivers and high capacitive load drive applications.

With an industry-leading maximum offset and lowest voltage noise of 5.7 nV/√Hz for 27-V amplifiers in the 100- to 200-MHz bandwidth range, the OPA2810 op amp allows engineers to achieve more precise measurements in data-acquisition and signal-processing applications. According to TI, the OPA189 is the widest bandwidth zero-drift op amp with the lowest noise of 5.2 nV/√Hz. With a low maximum drift of 0.02 μV/°C, the OPA189 also minimizes temperature error without calibration, increasing system accuracy over an extended temperature range.

The 120-MHz OPA2810 op amp offers best-in-class current consumption of 3.6 mA, while providing excellent signal-to-noise ratio and distortion. Designed for applications that require high gain and low distortion in power-sensitive designs, the OPA189 is the lowest power zero-drift op amp with a 14-MHz bandwidth. This device enables engineers to design high-resolution, noise-sensitive industrial systems while only consuming 1.3 mA of quiescent current, which can benefit analog input modules, and battery and LCD test equipment. TI’s new high-voltage amplifiers are available with at prices ranging from $1.98 to $6.20.

Texas Instruments | www.ti.com

Fault Protection Solution Defends High-Speed USB Ports

With the MAX22505 ±40 V high-speed USB fault protector from Maxim Integrated Products, system designers can now eliminate USB port damage from all faults, including ground potential differences, up to ±40 V without the tradeoffs required by competing solutions. It protects data and power lines from industrial equipment powered at 24 VAC and 40 VDC, while also reducing solution size by more than 50% for industrial voltage applications.
Industrial environments continue striving to reduce solution footprint to increase productivity and throughput while demanding system robustness and increased uptime. As a result, there has been a trend to adopt USB vs. RS-232 on automation equipment due to a much smaller connector size. As industrial environments adopt USB to provide faster communication for applications such as real-time diagnostics, programming/service ports on programmable logic controllers (PLCs), or supporting camera vision systems, USB ports require fault protection from overvoltage and ground differences while balancing the need to support high-speed data rates up to 480 Mbps.

Damage to both the host and device side can occur in these systems, requiring a unique solution that achieves high levels of fault protection. Existing USB fault protection solutions on the market today compromise either USB operating speed or voltage/current limit protection on a device’s data and power lines. Consequently, current solutions on the market are costlier and incapable of providing fault protection at high-speed USB performance.

The MAX22505 answers this market need as a solution that combines high-speed USB fault protection (480Mbps) for industrial voltages, while being flexible enough to support either host or device applications including USB On-The-Go (OTG). It protects equipment from overvoltage or negative voltage on power and data lines, as well as ground potential differences between devices. It reduces solution size by more than 50% compared to competing solutions and ensures robust communications in harsh environments cost-effectively in a simpler design. Housed in a 24-pin 4mm x 4mm TQFN package, it operates over the -40°C to +105°C temperature range. Applications include building automation, industrial PCs, PLCs and diagnostic USB ports.

The MAX22505 is available at Maxim’s website for $2.24 (1000-up, FOB USA); also available with select authorized distributors The MAX22505EVKIT# evaluation kits are available for $110

Maxim Integrated | www.maximintegrated.com