Grand launch | MT5785: 100W ultra-fast wireless charging and 18W reverse transmission

With the maturity of wireless charging technology, wireless charging have been widely applied and popularized. From mobile phones, watches, PADs, electric toothbrushes, electric toys to wireless charging automobiles, a wireless charging ecosystem has been formed.

The new launched wireless charging receiver MT5785 is a highly integrated SoC Wireless charging receiver based on magnetic induction which integrates all necessary components for wireless charging receiving function. It is capable of true fast wireless charging for up to 100W of delivered power and 18W of reverse charging, and features high power, high performance, high integration and so on. The chip is a global high-end wireless power receiver, has been mass produced on the latest flagship mobile phones such as the Honor Magic 4 Pro/Magic series.

• Power delivery: up to 100W

• Power delivery in Tx mode: up to 18W

• Up to 98% efficiency, low power consumption

• Supports small inductance coil application

• Q factor detection accuracy: <2%

• Current sample accuracy: <1%

• Unique OVP ensures system reliability

MT5785 typical application circuit

• Multiple core innovative technologies to achieve high efficiency and reliability

MT5785 adopts independent developed robust and reliable high efficiency rectifier bridge tech, half bridge startup tech, digital ADK/FSK modulation tech etc., solving relatively low charging efficiency problem in high current applications. It is capable of receiving 100W power and delivering 18W power to other devices, achieves up to 98.5% AC-DC conversion efficiency, which greatly improves the system efficiency and reliability, bringing better user experience.

MT5785 AC to DC efficiency curve

• Accurate FOD tech ensures system safety

In high power (100W) applications, a 2% current error can cause a 2W power error, posing a significant safety risk. MT5785 adopts high accuracy low voltage difference Power LDO and forward/reverse current sample tech, achieves lower than 0.4%@5A current sample accuracy by integrating high accuracy and low noise amplifier combined with software algorithms. Capacitive coupling technology is used for Q value detection to ensure that the LC resonator has no energy loss during free oscillation, and achieves more accurate detection of foreign objects with extremely low power consumption, ensuring the safety of wireless charging of mobile phones and other portable devices under high power applications.

• Reliable OVP over the entire power range

With self-developed reliable OVP technology, MT5785 is capable of detecting and distinguishing the abnormal condition that may cause over voltage by pre-setting the internal current/voltage sensor, and making the most reasonable response. It simultaneously supports an external bleeder resistor and the lowside MOSFETs of internal rectifier bridge can be shorted automatically, which greatly improves the safety of electrical equipment during charging.

 Terminal applications of wireless charging IC

Maxic has a number of targeted wireless charging products for different terminal applications or products, covering different power levels (1W~100W), different packages (WLCSP, QFN, FCQFN), and different data storage forms (OTP, MTP, and FLASH).

Development history of Maxic’s wireless charging IC