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Some of my SMPS circuits

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Here are a few of the SMPS circuits I made, employing flyback, push-pull, half-bridge and full-bridge topologies. _________________________________________________________________________________________________________________________  Test setup on verroboard of half-bridge SMPS circuit with SG3525 and IR2110 for battery charging. See description below. This is the verroboard prototype of the circuit built on PCB below. _________________________________________________________________________________________________________________________ Offline Half-bridge converter Input: 160 to 240V AC 50/60Hz Output: 14.5v 10A (max) Final test circuit (on PCB) for battery charging. Successful. To be incorporated in SMPS inverter with charger. The primary side PWM is controlled by SG3525 PWM chip. Frequency of operation is around 50kHz. The output signals of the SG3525 are fed into a IR2110 high-low side driver which drives the 2 MOSFETs (IRF840) configured for half-bridge topology. E...
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Using the SG3525 PWM Controller - Explanation and Example: Circuit Diagram / Schematic of Push-Pull Converter

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PWM is used in all sorts of power control and converter circuits. Some common examples include motor control, DC-DC converters, DC-AC inverters and lamp dimmers. There are numerous PWM controllers available that make the use and application of PWM quite easy. One of the most popular of such controllers is the versatile and ubiquitous SG3525 produced by multiple manufacturers – ST Microelectronics, Fairchild Semiconductors, On Semiconductors, to name a few. SG3525 is used extensively in DC-DC converters, DC-AC inverters, home UPS systems, solar inverters, power supplies, battery chargers and numerous other applications. With proper understanding, you can soon start using SG3525 yourself in such applications or any other application really that demands PWM control. Before going on to the description and application, let’s first take a look at the block diagram and the pin layout. Pins 1 (Inverting Input) and 2 (Non Inverting Input) are the inputs to the on-board error amplifier. If you a...
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N-Channel MOSFET High-Side Drive: When, Why and How?

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I had previously shown how to drive N-channel MOSFETs in low-side configuration. You can find the tutorial here: http://electel.blogspot.com/2016/12/low-side-mosfet-drive-circuits-and_23.html I’ve been requested to write a tutorial/article regarding high-side MOSFET drive. So, here I’ll talk about N-channel MOSFET high-side drive. Let’s first look at the common low side configuration.  Fig. 1 - N-channel MOSFET configured as low-side switch Now let’s look at a MOSFET configured as a high-side switch. Fig. 2 - N-channel MOSFET configured as high-side switch You can quite easily see the difference between the high-side configuration and the low-side configuration. In the low-side configuration, the load is connected between the drain and +V, while the source is connected to ground. Thus, the gate drive is referenced to ground. So by applying a voltage of >7V (for Power MOSFETs) or >4V (for Logic Level MOSFETs), the MOSFET can be fully turned on. Now let’s talk about the high-si...
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