| 摘要 |
A gas sensor instrument in which a diffusion chamber has conductive walls and a sensor is disposed inside the diffusion chamber. A regulated voltage source provides the input to a charge pump (240) and the charge pump thus generates an output voltage (VBias)of greater magnitude than its input voltage. The use of a regulated voltage source as the input leads to a more regulated output voltage from the charge pump. The output of the charge pump is arranged to provide a stable electric field between the sensor and the conductive walls of the diffusion chamber. Preferably the regulated voltage source is taken from the LCD supply pin (205) of a microcontroller (200). |
