Abstract: An information handling system includes a printed circuit board. The printed circuit board includes first and second pads of a first differential pair, a hatched ground, and first and second traces of a second differential pair. The first and second pads of the first differential pair are routed a surface of the printed circuit board. The hatched ground routed within a first layer of the printed circuit board. The first and second traces of the second differential pair are routed below the first and second pads and the hatched ground within a second layer of the printed circuit board. The hatched ground dampens crosstalk between signals on the traces and signals on the differential pair pads.

Abstract: A first aspect of the present invention provides a method for the preparation of 2-chloro-5-chloromethylpyridine, comprising: performing a cyclization reaction on 4,5-dichloro-4-methoxypentanenitrile in presence of a silicon compound and an acylamide compound to obtain 2-chloro-5-chloromethylpyridine. Another aspect of the present invention provides a method for preparation of 2-(chloromethyl)-5-(trifluoromethyl)-1,3,4-oxadiazole, comprising: performing a cyclization reaction on 1-(chloroacetyl)-2-(trifluoroacetyl)hydrazine in a presence of a silicon compound and an acylamide compound to obtain 2-(chloromethyl)-5-(trifluoromethyl)-1,3,4-oxadiazole. The silicon compound or/and acylamide compound provided by the present invention serve as cyclization reagents and have high efficiency.

Abstract: A self-adaptive constant-current driving circuit for a three-channel multi-color LED, including a decoder, a two-phase non-overlapping circuit, and a LED constant-current driving circuit, where the decoder determines the number of lighted channels according to a first input signal, and generates a first switch control signal and a second switch control signal; the two-phase non-overlapping circuit modulates the first switch control signal into a first two-phase non-overlapping signal and a second two-phase non-overlapping signal, and modulates the second switch control signal into a third two-phase non-overlapping signal and a fourth two-phase non-overlapping signal; the LED constant-current driving circuit controls an on/off state of the respective channel of LED according to a second input signal, and outputs a current for controlling a brightness of the respective channel of LED according to the first two-phase non-overlapping signal, the second two-phase non-overlapping signal, the third two-phase non-ove

Abstract: An information handling system includes a printed circuit board. The printed circuit board includes first and second pads of a first differential pair, a hatched ground, and first and second traces of a second differential pair. The first and second pads of the first differential pair are routed a surface of the printed circuit board. The hatched ground routed within a first layer of the printed circuit board. The first and second traces of the second differential pair are routed below the first and second pads and the hatched ground within a second layer of the printed circuit board. The hatched ground dampens crosstalk between signals on the traces and signals on the differential pair pads.