1, abstract
Switching power supplies have penetrated into various industries in the national economy. Designers either design their own power supplies or purchase power modules, but these power supplies are inseparable from the various circuit topologies of the power supply. This article first introduces the three basic topologies of switching power supply: Buck, Boost, Buck-Boost, and simply combines these three topologies, and get very clever circuits, such as: positive and negative output power, bidirectional power Etc., can meet certain special needs such as op amp power supply, battery charge and discharge.
2, switching power supply basic topology
The three basic topologies of switching power supply are: Buck, Boost, and Buck-Boost. Most of the switching power supplies use these basic topologies or their corresponding isolation modes. The following is a brief introduction of the inductor continuous mode.
2.1 Buck step-down type
The Buck step-down circuit topology, sometimes called the Step-down circuit, has a typical circuit structure as shown in Figure 1:
The working principle of the Buck circuit is:
When the PWM drive high level causes the NMOS transistor T to be turned on, the conduction voltage drop of the MOS transistor is ignored, equivalent to FIG. 2, the inductor current rises linearly, and the forward volt-second of the inductor when the MOS is turned on is:
When the PWM is driven low, the MOS transistor is turned off, the inductor current cannot be abrupt, and the loop is formed by the freewheeling diode (ignoring the diode voltage), and the output load is supplied. At this time, the inductor current drops, as shown in Figure 3 below, when the MOS is turned off. The inductance reverse volts is:
D is the duty cycle, 0
2.2 Boost boost type
The Boost boost circuit topology, sometimes referred to as a step-up circuit, has a typical circuit structure as shown in Figure 4:
Similarly, according to the analysis method of the Buck circuit, the working principle of the Boost circuit is:
0
2.3 Buck-Boost polarity reversal lifting type
The Buck-Boost circuit topology, sometimes called InverTIng, has a typical circuit structure as shown in Figure 5:
1.25mm Wire To Board Connectors
1.25mm Wire To Board Connectors are avialable in different terminations and sizes intended for use on a variety of applications. These connectors provide power and signal with different body styles, termination options, and centerlines. To find the wire to board set required, click on the appropriate sub section below.
Description
1.25mm wire-to-board connector system is designed for a wide variety of applications in Industrial, Automotive, and Consumer markets.
The comprehensive range consists of terminals, crimp housings and PCB headers in straight and right angle, surface mount and through-hole configurations. It is available in 2 to 15 circuits in a single row. 1.25mm wire-to-board solution conforms to the EU Industry Safety Standard. PCB header material meets halogen-free requirements and can be operated in the temperature range from -40°C to +105°C.
Saves space with a 1.25mm pitch
Suitable for Industrial, Automotive, and Consumer markets
Crimp housing with friction feature
Conforms to EU Industry Safety Standard
Accommodates wire range up to 32AWG-28AWG
Features
Three plating versions - Tin 15μin Gold, 30μin Gold and Gold Flash
Fully polarized housings
Crimp housing with friction feature
Tape and Reel packaging with pick up cap
UL94V-0 flammability rated LCP material
Halogen-free resin material
RoHS compliant and lead-free
Benefits
Supports applications in a wide range of environments
Prevents accidental mismating
Provides additional retention and prevents harness-to-header mismating
Pick and place for SMT production process
High flammability rating
Meets environmental requirement
Meets environmental, health and safety requirement
Applications
Consumers
Car Audio
Industrial & Instrumentation
Industry Control
Instrumentation/Metering
Office Equipment
Small Motor/Robot Control
Security
Alarm Systems
Vending POS Machine
Automotive Connectors,1.25Mm Wire To Board Connectors,1.25Mm Pcb Wire To Board Connector,1.25Mm Pin Wire To Board Connector,.049" Pitch Wire To Board Connectors
ShenZhen Antenk Electronics Co,Ltd , https://www.antenkwire.com