Electronics Weekly
Called ADHV4710, the output can swing ±52V with ±100mA loading, and its rails can vary down to ±12V.
Despite being able to drive ±1300V/μs into 1nF, it is a voltage feedback amplifier, that can handle unlimited capacitive loads due to a modified signal path that allows external compensation and output slew rate limiting.
Boosting large signal bandwidth is a circuit that temporarily increases the amplifier’s bias currents, there by momentarily speeding it up, if the two inputs develop a voltage across them – indicating that the feedback is not keeping up with the input signal.
Small and large signal bandwidth are similar at 2.5MHz with a 100mVp-p output and 2.3MHz at 80Vp-p.
Further signal path modifications allow the amplifier to be configured with high gain for low input voltages, or low gain for high input voltages.
All negative-feedback configurations can be accommodated: non-inverting, inverting or differential.
Wrapped around the analogue signal path is a digital control system with a 19MHz four-wire SPI serial interface that sets current, voltage shutdown limits and quiescent current, for example, and also monitors junction temperature and reports fault protection status.
Digital control is compulsory – there is no stand-alone mode.
A separate 5V input rail is needed to supply internal low-voltage circuitry, and a separate 5V reference must be provided against which programmable limits are set. This reference input can be connected to the 5V power rail if reduced limit accuracy can be tolerated.
The output is short-circuit protected, but not under all circumstances due to features including a programmable short-circuit protection delay and the large signal bandwidth booster.
Ambient temperature range is -40 to +85°C.
Packaging is an 80pin TQFP that measures 14 x 14mm including legs and has a thermal pad on top. With the recommended heatsink (Wakefield-Vette 518-95AB), it can handle up to 19W before the internal temperature reaches its 150°C maximum.
Use if foreseen as a power amplifier, programmable power supply, arbitrary waveform generator output or piezoelectric transducer driver.
