Background

Nowadays, wireless charging is becoming more and more popular, as many enthusiasts say，I don't need to use it，but you can't do without it, at present, the flagship mobilephone almost has to have wireless charging function.So if I put the device on the wireless charger while charging with the data cable，what is charging at this time?If you don't deal with it, two-way power supply are bound to conflict. However, this conflict can be resolved by ET9902.

 

ET9902 Function Introduction
ET9902 is a high voltage and high current bidirectional load switch，in addition to the input overvoltage and electric surge protection functions of ordinary OVP，it also provides the reverse blocking selection function of the output voltage. The logic control of the device can be used to interact with the system controller and the wireless charging receiver.

Typical application

When charging with an addpter，ET9902 outputs RX signal to inform the wireless cgarging system RX end to close the wireless charging module.When using wireless charging,its output can cut off the output of wireless charging,avoid voltage backflow to the USB port. It also supports OTG function.

Surge Model
1. Open Voltage Model（1.2/50μs）

 

2. Short Current Model（8/20μs）

ET9902 integrates a surge tube that can withstand more than ±100V. Under 100V surge, the waveform is as follow：
 

OVP Fast Shutdown
In addition to being resistant to 28V DC withstand voltage, the USBIN port of ET9902 also supports two overvoltage shutdown functions.Through the state of the VP terminal, two overvoltage protection options of 13V/17V can be provided,and the overvoltage shutdown response time is within 100ns.

OTG Function
When the system detects that the OTG device is inserted, the channel from OUT to USBIN will be opened by giving the corresponding signal to FLAG-N, thereby supplying power to the OTG device.

 

  Feature

Two-way Switch From USBIN to OUT, Supporting OTG Mode
Input Voltage Range：3V~20V，MAX Input Voltage: 28V
Optional Overvoltage Protection Point :13V/17V
Very Low Internal Resistance:RON =23mΩ
5A DC Load Capacity
±100V Surge
Wireless Charging Enable Output
Autonomous Mode And Slave Mode
Green WLCSP20（1.67mm x 2.24mm）Package