STMicroelectronics Enhances Current Sensing for Improved Control, Efficiency and Safety
News Release from:
22 June 2010
STMicroelectronics has unveiled a chip that simplifies the design of power management, monitoring and safety equipment by allowing direct and accurate measurement of current in power lines operating at up to 70V.
Accurate current measurements are essential when managing the delivery of power in various automotive, telecom and industrial systems. The information can be used to optimize power consumption or to identify faults such as a failed power supply or jammed motor, which can cause excessive current to flow. Current is usually sensed using a series shunt resistor and a network of traditional amplifiers, an approach that complicates design, imposes high power losses and limits accuracy.
The TSC103 is the latest in ST’s family of high-side current-sense amplifiers, which simplify design by connecting directly to power-supply lines at high voltages. This approach requires only a small sensing resistor and consumes less power than the conventional solution. The TSC103 accepts a common-mode input from 2.9V up to 70V and measures current more accurately than similar competing devices. The common-mode input range can also be set from -2.1V to 65V in dual-supply configurations, with outstanding stability of the accuracy versus common-mode voltage. The output is proportional to the measured current and can be connected directly to the analog input of a microcontroller.
In addition to the TSC103, ST has also introduced the TSC1031, featuring enhanced EMI filtering to maintain performance in electrically noisy environments. Both devices have adjustable sensitivity that allows their use in diverse applications, such as 24V vehicle systems, 48V telecom equipment, multi-LED display backlights, or solid-state lighting. The devices are fully ESD specified for rugged performance and they can operate from -40°C to 125°C.
Major features of TSC103/TSC1031:
* 2.7V to 5.5V operating supply voltage
* Selectable output gain: 20V/V (TSC103 only), 25V/V (TSC103 only), 50V/V, 100V/V
* Maximum 360-microamp current consumption
* 2.9V to 70V common-mode input range
* -2.1V to 65V common-mode input range in dual-supply configuration
* -16V to 75V common-mode surviving range, to withstand reverse-battery and load-dump conditions