Description: The HIP9011 is used to provide a method of detecting premature detonation often referred to as Knock or Ping in internal combustion engines. The IC is shown in the Simplified Block Diagram. The chip can select between one of two sensors, if needed for accurate monitoring or for V type engines. Internal control via the SPI bus is fast enough to switch sensors between each firing cycle. A programmable bandpass filter processes the signal from either of the sensor inputs. The bandpass filter can be selected to