Multipath switching circuit, chip and communication terminal

Abstract

The invention discloses a multipath switching circuit applied in a solid antenna switch. The multipath switching circuit comprises common gate switch transistor groups connected in series and arranged between a radio-frequency signal input end and a signal output end, and a source drain bias resistor network arranged between a source of a first crystal switch tube which is connected to the signal input end and a drain of a last crystal switch tube which is connected to the signal output end. The multipath switch circuit provided by the invention can effectively improve linear characteristics of a path switch. The invention further discloses a chip including the multipath switch circuit and a communication terminal including the multipath switch circuit or the chip.

Description

technical field [0001] The invention relates to a multi-path switch circuit for a solid-state antenna switch, a chip containing the circuit and a communication terminal, belonging to the technical field of integrated circuits. Background technique [0002] Solid-state antenna switches have been widely used in wireless mobile communication front-end modules or multi-path antenna switch modules. In the rapidly developing multi-mode and multi-band smartphone system, the number of modes and frequency bands is constantly increasing, which requires more and more paths in the antenna switch, while maintaining or even improving its dropout and linearity characteristics . [0003] In the prior art, the structural block diagram of a typical multipath antenna switch is as follows figure 1 shown. When the switch of one of the paths is turned on, the switches of other paths are turned off at the same time, so that only the radio frequency signal connected to this path can be transmitt...

AI Technical Summary

Problems solved by technology

In addition, on the one hand, when each switching transistor is turned on, since there are parasitic capacitances between the source and the gate and the drain and the gate of the switching transistor, a part of the radio frequency signal will leak from the source and the drain to the gate, Thus affecting the differential loss characteristics of the switch; on the other hand, when the switching transistor is turned off, the channel between its source and drain is closed, but there is also a parasitic capacitance between the source and drain, which will also affect the switch's Linearity

[0006] In the prior art, for a given integrated circuit process, although increasing the gate width of the transistor can reduce the differential loss of the switch and improve the linearity, it is limited by the chip area, that is, the design cost; at the same time, due to the parasitic Capacitance, its degree of performance improvement will gradually become saturated

On the other hand, although many semiconductor manufacturers are currently committed to developing new processes and switching devices, their development cycle is long and the cost is high.

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