Patent ID: 9030257
Filing Date: 2015-05-12
Classification: H03F,H04B

Abstract:
1. A differential circuit, comprising: an amplifying unit with a pair of hetero-bipolar transistors to convert a mono-phase input signal received by one transistor of the paired transistors into two output signals complementary to each other; a first low-pass filter coupled with the other of the paired transistors and having a cut-off frequency smaller than a transition frequency of the other of the paired transistors; and a second low-pass filter to generate an average of the two output signals the average being provided to the other transistor of the paired transistors via the first low-pass filter, wherein the other transistor of the paired transistors shows a self-heating effect below the transition frequency, wherein the first low-pass filter and the second low-pass filter have an emitter follower therebetween, and wherein the cut-off frequency of the first low-pass filter is 2 to 4 MHz.