Abstract: A detection circuit is provided herein, which includes a first transistor, a second transistor, a third transistor, a light sensor, a capacitor, and a fourth transistor. The first transistor has a control terminal, a first terminal, and a second terminal. The second transistor is coupled to the control terminal. The third transistor is coupled to the control terminal and the second terminal. The light sensor is coupled to the control terminal. The capacitor is coupled to the control terminal. The fourth transistor is coupled to the second terminal.

Abstract: After a solution of chloropropyltriethoxysilane and sodium thiocyanate react in ethanol to form a thiocyanatopropyltriethoxysilane suspension, salt resulting from the reacting step is removed from the ethanol-containing centrifugate and washed. The first embodiment for manufacturing thiocyanatopropyltriethoxysilane includes adding the wash ethanol to the solution in the reacting step, distilling the centrifugate to remove ethanol, and removing solids from a thiocyanatopropyltriethoxysilane residue resulting from the distilling step. The ethanol from the distilling step may be used to wash the salt separated in the centrifugating step.