Single FireWire power supply is the most important part of intelligent switches (such as touch switches, wireless remote control switches, Zigbee switches, etc.), and its core technology is the single FireWire power-picking technology. Figure a1 Product Physical Map Figure a2 Pin diagram Figure a3 Package Dimension Rice Huller Head,Rice Milling Machine Head,Huller Head,Huller Machine Hunan Nongyou Machinery Group CO.,LTD , https://www.ricemill.nl
The control diagram of the single fire intelligent switch is as follows: 
The technical difficulty of the single FireWire intelligent switch: Since the single FireWire switch takes any point of electricity, it needs to flow through the lamp. When the power consumption of the switch is greater than about 220V/50uA, when the power reaches the internal capacitor charging requirements of the lamp. When the instantaneous current is formed, a small power W lamp, such as a 2W LED, is bound to flash. Because of the 2W lamp, it lights a small current = 2W/220V = 9mA. This is commonly known as "wildfire", that is, the phenomenon of flickering in the off state of the lamp (refer to read: single-wire electronic switch with energy-saving lamps (LED lights will flash). 
For wireless remote control smart switches that require remote control, it is bound to need more power, but also to balance the "wildfire" problem, so this is the difficulty of single fire line power. The instantaneous current required for the switching operation is at least 2mA (315MHz) or 30mA (ZigBee). Therefore, for a ZigBee switch product with a large current demand, it is more difficult to take a single firewire.
In order to obtain an ideal single-firing power supply solution, after years of fundamental research and technical breakthroughs, Dongguan Xundi Electronics Co., Ltd. has developed a series of miniaturized module power supplies suitable for single-firing intelligent switch products. 
Low-power, low-power power supplies are mainly used in smart home implementation units (such as smart switches, smart sockets) or in small controllers. The power supplies used in this area are usually AC/DC (DC/DC) low-power products. The minimum application requirements may be within 1W, and products with slightly more complex functions may use 2W-5W power supply products. The product requirements are as follows:
(1) Small size, easy to install in a standard enclosure;
(2) Ultra-low power consumption, which reduces the standby power consumption of the product or the "ghost fire" phenomenon of the smart switch (3) High efficiency and low heat;
(4) The low failure rate and stable and reliable quality are the primary factors of the product.
This series of products is a super-small DC/DC (AC/DC) power supply with a SIP4 pin structure. Its size is L18*W9.5*H15.5mm, which is a small size for this type of power supply in the industry. Its characteristics due to the use of advanced circuit structure, the cost has been well controlled, very suitable for a wide range of applications in smart home appliances such as smart switches, has been successfully applied to a number of smart home products, such as smart socket (zero FireWire), Smart Switch (single FireWire), etc. Specific product parameters can refer to:
Dongguan Xundi Electronics Co., Ltd. Website:. . Com.
Dongguan Xundi Electronics Co., Ltd. developed and launched the PI series of ultra-small integrated smart home single FireWire power supply module, the input voltage range is very wide (13V-380V), the output power is larger (200mA), the output voltage is optional (3.3V, 5V, etc.), lamp load range is wide (1W-3000W), low power consumption and low heat. Can provide stable working power for control circuits (such as dedicated control ICs, MCUs, infrared receiver heads, RF remote control modules, ZigBee modules, Bluetooth modules, relays or thyristors, etc.) 
Features:
â— Ultra-wide input voltage: 13-380VDC
â— Output protection function: short-circuit and over-current protection â— High efficiency: the maximum efficiency of the power supply> 65%;
â— large current: output maximum current 200mA;
Low power consumption: the power consumption is less than 5mW when no load is output;
Internal integrated LDO circuit: stable output 5V voltage (3.3V/3V), no need for external additional voltage regulator IC circuit â— ultra-small size: L18*W9.5*H15.5m 
[Attached] reference application circuit schematics <br> <br> single FireWire switching applications circuit diagram (The following is the single FireWire power supply section, the complete three-way switch circuit schematics accessible Dongguan City Xun Di Electronics Co., Ltd. Web site to download):
Component selection:
R1 current limiting resistor, depending on the input voltage range and output current.
C1 filter capacitor, it is recommended to use 0.47uF-100uF electrolytic capacitor, depending on the input voltage range and output current.
C2 uses 47uF/25V electrolytic capacitor.
C3 output filter capacitor, it is recommended to use 47uF-220uF.
Z1 is not more than 12V for output modules below 12V; it is not more than 15V for 12V output modules.
Note: If the quiescent current requirements are relatively stringent, it is recommended that C1-C3 should use a capacitor with a smaller leakage current as much as possible.
The single FireWire power module provides an ideal and convenient single FireWire power supply solution for many smart home companies to develop smart switches (single FireWire module or single FireWire module for ZigBee touch switches and other products).