Micro-power consumption and ultra-small package dual-channel single-pole double-throw analog switch RS2323 is used for TWS headphones, and the switch is switched.

TWS true wireless stereo earphone consists of charging box, left earphone and right earphone. When the earphone is placed on the seat of the charging box, automatic identification and charging can be realized between charging and earphone. In order to improve the efficiency of identification and matching between headphones and charging box, the current trend is to reuse the charging port and communication port, and it is not necessary to identify them by Bluetooth communication. When charging headphones, the charging current of the charging box is generally about 100mA, and the highest frequency of the communication line will not exceed 1MHz.

In order to realize the reuse of charging port and communication port, it is necessary to add analog switches to achieve the purpose of time-sharing multiplexing. The requirements for analog switches are as low as possible, allowing hundreds of mA current to pass, and having a certain bandwidth.

The analog switch product recommended here is a dual-channel single-pole double-throw analog switch, which can be used to process analog and digital signals, with high switching speed (50ns) and low on-impedance (0.6 ohm). In this way, the switching between the charging port and the communication port on the TWS headset and the charging box can be realized quickly with little loss. The input power supply voltage range is wide, from 1.8V to 5.5V, and the current consumption is only 1uA. So that the power consumption of the analog switch itself is very low. Rail-to-rail mode is adopted to support TTL/CMOS levels.

The two channels of RS2323 are completely independent, and they are switched by pins in1 and in2. The NC and NO pins are normally open and normally closed ports, respectively, and the COM port is a common port. The maximum continuous current can withstand ±500mA, and the peak current can reach ±800mA. The package size of RS2323 analog switch with UTDFN 10 is only 1.4mm x 1.8mm, and the industrial temperature range is -40 to 125°C, which can meet the requirements of TWS headphones for small volume and long-term stability and reliability. Figure 1 below is the package and pin definition diagram of RS2323 analog switch.