4.5 W Non-Isolated Buck Power Supply

本設(shè)計(jì)用于提供非隔離額定輸出電壓為15 V，負(fù)載為300 mA，輸入電壓范圍為60VDC至550 VDC用于汽車應(yīng)用，非常值得嘗試。

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The schematic in Figure 2 shows a buck converter using LNK3206GQ. The circuit provides a non-isolated 15 V, 300 mA continuous output. In this design, automotive battery will be the intended input source of the buck circuit. To simulate battery stiff voltage source, bulk capacitors was added in the test setup during the test as shown in Figure 3. The LinkSwitch™-TN2 family of ICs for automotive power supplies provide significant reduction in component count compared to traditional discrete solutions. Regulation is achieved using a low cost resistor divider feedback network. The switching frequency jitter feature of the LinkSwitch-TN2 family and the 66 kHz switching frequency of operation helps reduce EMI. Each device incorporates a 750 V power MOSFET, oscillator, On/Off control, a high-voltage switched current source for self-biasing, frequency jittering, fast (cycle-by-cycle) current limit, hysteretic thermal shutdown, and output and overvoltage protection circuitry onto a monolithic IC. LinkSwitch-TN2 ICs consume very little current in standby resulting in power supply designs that meet <50 mW no-load input at 400 VDC input. A full suite of protection features enable safe and reliable power supplies protecting the device and the system against input and output overvoltage faults, device over-temperature faults, lost regulation, and power supply output overload or short-circuit faults. Due to automotive application, all component selected are AEC compliant. 

PCB設(shè)計(jì)也很簡(jiǎn)單，有興趣可進(jìn)一步到PI官網(wǎng)了解。