PA176 Power supply circuits1 Power supply circuits Ing. Jiří Čulen 16.03.2023 PA176 Architecture of Digital Systems II PA176 Power supply circuits2 Something about me  Ing. Jiří Čulen, jiri.culen@mail.muni.cz www.vfnuclear.com. • Designer of devices for ionizing radiation monitoring on nuclear power plants, nuclear medicine and industry since 2001 • PCB design in Altium Designer + Concorde Pro • CPLD and FPGA design in Xilinx ISE, Vivado and Vitis Customer Segments Nuclear Industry 3 VF, a.s. Radioactive Waste Management Medical Industry Environmental Monitoring Metrology and Calibration Dismantling and Decommissioning . 4 Area and process monitoring VF, a.s. . 5 Contamination Monitors VF, a.s. PA176 Power supply circuits6 Power supply circuits ̶ Most of the components in PCBs are not implemented due to the main function, but most of it is auxiliary and supporting for main components. ̶ Typically, more then 50% of this auxiliary components are power supplies. PA176 Power supply circuits7 Power supply circuits AC/DC DC/DC DC/DC Analog. DC/DC MCU DC/DC low noise MCU CPLD FPGA Overvoltage suppression DC/DC I/O Amplifiers, filters, … Comparators, ADC, … RS-485 RS-422 USB DAC relé Overvoltage suppression Power Signal input I/O ̶ The typical structure of (not only) measuring instruments: PA176 Power supply circuits8 Power supply circuits 5 / HV 24 / 5 ISO 5 / 3,3 3,3 INV 5V / 5V ISO F F F F 1, 8 ̶ Example of PCB for scintillation detectors: PA176 Power supply circuits9 Power supply circuits Linear Power Supply + low noise - low efficiency, only for decreasing of voltage Switching Power Supply + high efficiency, decreasing, increasing, inverting and galvanic isolation of voltage - high noise 10 Linear Power Supply PA176 Power supply circuits The basic linear voltage regulator 11 Linear Power Supply Principial schematic of linear regulators – feedback loop PA176 Power supply circuits 12 Linear Power Supply Principial schematic of linear regulators – LDO PA176 Power supply circuits 13 Linear Power Supply Ultralow RMS Noise: 0.8μVRMS (10Hz to 100kHz) PA176 Power supply circuits 14 Switching Power Supply ̶ Most of switching power supply are based on accumulation of energy. ̶ Accumulation of energy is based on magnetic field (chokes, transformers), on capacitors or on combination of both. PA176 Power supply circuits 15 Switching Power Supply Buck (step down) topology – decreasing of voltage PA176 Power supply circuits 16 Switching Power Supply Buck (step down) topology – decreasing of voltage PA176 Power supply circuits 17 Switching Power Supply Boost (step up) topology – increasing of voltage The problem: Not isolating of short circuit PA176 Power supply circuits 18 Switching Power Supply Boost (step up) topology – increasing of voltage PA176 Power supply circuits 19 Switching Power Supply Flyback (inverting) topology – inversion of voltage PA176 Power supply circuits 20 Switching Power Supply Flyback (inverting) topology – galvanic isolation - transformer with air gap (difference from pass-through DC/DC) - up to approximately 200W PA176 Power supply circuits 21 Switching Power Supply Flyback (inverting) topology – galvanic isolation PA176 Power supply circuits 22 Switching Power Supply SEPIC topology – increasing/decreasing of voltage PA176 Power supply circuits Uin 23 Switching Power Supply SEPIC topology – increasing/decreasing of voltage PA176 Power supply circuits 24 Switching Power Supply ČUK topology – inversion of voltage PA176 Power supply circuits |Uin| + |Uout| 25 Switching Power Supply ČUK topology – inversion of voltage PA176 Power supply circuits 26 Switching Power Supply Combination of SEPIC and ČUK topology – symmetric voltage PA176 Power supply circuits 27 Switching Power Supply Charge pump – voltage doubler - Very low self consumption - Not possible to regulate output voltage PA176 Power supply circuits 28 Switching Power Supply Charge pump – voltage invertor - Very low self consumption - Not possible to regulate output voltage PA176 Power supply circuits 29 Switching Power Supply Charge pump PA176 Power supply circuits 30 Filters for power rail Decreasing of noise and decreasing of crosstalk's PA176 Power supply circuits 31 Filters for power rail The best filters for low and medium frequency are linear regulators PA176 Power supply circuits 32 Starts of power supplies It is necessary to be careful about shape, inrush current, rise times and order of voltages. PA176 Power supply circuits 33 Starts of power supplies It is necessary to be careful about shape, inrush current, rise times and order of voltages. PA176 Power supply circuits 34 Examples of design in the Altium Designer PA176 Power supply circuits 35 References PA176 Power supply circuits [1] Texas Instruments, Power Topologies Handbook [2] Analog Devices, LTspice simulator PA176 Power supply circuits36 Thank you for attention Ing. Jiří Čulen jiri.culen@mail.muni.cz