GOAL Semiconductor, represented in Australia by Alfa-Tek , has released the HVDAC 200 high-voltage, four-channel, nine-bit, serially-configurable voltage/current D/A converter. It is capable of output of over 200V.
The HVDAC targets applications in the industrial, telecommunications, automotive, medical and consumer markets that require high voltage control. These include MEMs drivers, variable optical attenuators (VOA), industrial printers, level translation, optical controllers, fibre optic applications, piezoelectric transducer drivers and HV bias generation.
It is based on a nine-bit current DAC architecture and can operate in either current or voltage mode. The output range of the DAC outputs is controlled by a low-voltage reference input and each channel includes a five-bit output offset adjustment. The output range of the HVDAC can be adjusted from 20V to 200V.
It has two maximum output currents: 500µA and 5mA. A 600kΩ resistor is integrated at each channel output to provide voltage output range. Channels also include an over-current limit protection feature and the HVDAC incorporates a temperature sensor that can monitor device temperature and engage shutdown in case of overheating.
Communication with the HVDAC is executed serially via an SPI interface that includes a signal retransmission feature so that users can daisy chain multiple devices on a single SPI bus. The device also includes a hardware reset that clears the internal registers.
The integration of digital and high-voltage control circuitry on a single chip means the HVDAC 200 reduces the number of components required for high-voltage control applications, allowing for more compact system designs.
By incorporating a current limitation circuit on each channel as well as a temperature sensor, the device simplifies system condition monitoring and improves reliability. Multiple device usage on a single communication interface permits further system integration and increases flexibility. The daisy-chainable SPI allows the HVDAC to interface with a microcontroller directly and permits the networking of multiple HVDACs on the same system. The DAC offset output can be calibrated to suit specific application needs by using the five-bit offset control on each DAC output.