The importance of the two OVP is that one is overvoltage protection, and the other is that input can from 30V resistance to 30V, reaching 36V, 40V,
With the renewal of electronic products, the power of electronic products in the past is generally low, and the voltage is also low. For example, mobile phone charger, thinking that it is 5V500MA or universal charging directly charging the battery, and then to Apple's 5V1A, and then 5V2A, to 5V2A, and then to 5V2A, it is 5V2A, and then 5V2A. Then to 5V4.5A, and then 9V2A, 12V, 20V, etc., the voltage of the charger is getting richer and richer.

 When the circuit is called, the moment the power is called, a high peak voltage often generates a high peak voltage. The method of reducing peak margins is generally line impedance (resistance, disadvantages can only be used at very small currents) and the equivalent series resistance (electrolytic capacitance, large disadvantage volume, high height) or OVP overvoltage protection chip PW2606 or PW1515 series Essence

             As shown in the figure below, the USB port 5V input, because it is generated at the moment of power -on, universal meters, human eyes and other conventional instruments cannot be measured. Use an oscilloscope to set 100 milliseconds. As can be seen from the figure below, the peak voltage of the instantaneous moment of 5V can reach about 8V, or even higher. For some chips with low voltage resistance, it is easy to break the chip because of instant overvoltage; There has always been a high rate of adverse rates, which is also a possible reason.

The figure below is 200 milliseconds for a single detection time. Enter 5V, power -on and disconnected the waveform of the USB. The peak voltage generated can also be seen. The characteristic is: 1. It is generated at the moment of power-on. 2. The general peak voltage is about 2-3 times the input voltage.

The popularity of fast charging high -voltage chargers, more and more foreign customers require USB port to resist 28V to take up voltage, 5V input product overvoltage protection 6.1V can be protected and closed, such as Bluetooth headsets, speakers, electric toothbrushes, table lamps, charging treasures, magnetic magnetic treasures, magnetism Products, electronic tools and other products.
PW2606/PW2606B is the front -end overvoltage and over -current protection equipment. It implements a wide input voltage range from 2.5V to 40V. Over -pressure threshold fixed internal OVP threshold: 6.1V. For example, add 4054,4056, etc., as shown in the figure below


OVP overvoltage protection chip, overcurrent protection chip, lithium battery charging chip with OVP overvoltage protection

The short-circuit risk of the QC fast charger controller of the USB Type-C PD or the USB A port is also high, because the device directly connects the CC pin and designed the maximum operating voltage to 5 V. During the USB PD period, the PD controller is responsible for coordinating the maximum current and voltage level between the charger and the charging device, so it is very important to protect these devices. The USB PD is abnormal operation caused by the damage of the PD controller, especially when some low -quality and cheap PD charger uses a low -cost PD controller, it may become a hidden danger of safety, output high voltage, and for electronic products that are not enough to resist voltage protection, Once connected to charging, it may cause damage to the product.

OVP overvoltage protection chip is currently the most domestic application field, which is closely related to everyone.
That is Bluetooth headset.