A kind of vcsel anode driving circuit and method

Abstract

The invention provides a VCSEL anode driving circuit comprising a first switching tube branch and a second switching tube branch which are opened in turn. The first switching tube branch is sequentially connected with a first output impedance and a first switching tube, and the node of the first output impedance and the first switching tube is connected with a power supply after passing through anauxiliary impedance; the second switching tube branch is sequentially connected with a second output impedance and a second switching tube, and the node between the second switching tube and the second output impedance is connected with a VCSEL laser and then grounded. The first output impedance and the second output impedance are mutually connected, the first switching tube and the second switching tube are connected and then connected with tail current, and the other end of the tail current is grounded; the signal input end is connected with the control ends of the first switching tube andthe second switching tube through the input buffer stage; the first output impedance is equal to the second output impedance; and the auxiliary impedance is equal to the equivalent impedance of the VCSEL laser. The auxiliary impedance is introduced to match the equivalent impedance of the VCSEL laser so that the quality of an output signal is improved.

Description

technical field [0001] The invention belongs to the technical field of data optical fiber communication systems, and in particular relates to a VCSEL anode drive circuit and method. Background technique [0002] Due to the excellent performance and low price of VCSEL lasers, it is widely used in data optical fiber communication systems. As the data rate is getting higher and higher, in multi-channel data transmission, VCSEL arrays are gradually used in system solutions instead of single VCSELs, and the cathodes of each VCSEL in the VCSEL array are connected to each other, so the VCSEL driver can only be driven by the anode Methods. [0003] Due to the large transient current swing output by the VCSEL driver, a lot of noise will be generated on the power supply, and these noises will be superimposed on the output through the output impedance of the VCSEL driver, affecting the quality of data transmission. like figure 1 As shown, the input signal input pushes the switch pai...

AI Technical Summary

Problems solved by technology

[0003] Due to the large transient current swing output by the VCSEL driver, a lot of noise will be generated on the power supply, and these noises will be superimposed on the output through the output impedance of the VCSEL driver, affecting the quality of data transmission

like figure 1 As shown, the input signal input pushes the switch pair tube of the output stage through the input buffer stage. The switch pair tube is controlled by the input signal to open and close alternately, and the tail current Iss is guided to flow alternately on the left and right branches. Due to the existence of the off-chip VCSEL device, The currents flowing through the left and right branches are not equal. On the power supply, the current jumps with the input signal. Considering the bonding of the chip power supply and the influence of the parasitic resistance of the power supply wiring in the chip, the power supply Voltage noise will be generated on the circuit, and this noise will be divided to the off-chip VCSEL through the output impedance Z11, resulting in output noise and affecting the quality of the output signal

Images