Ultra-low power Bluetooth controlled, cost-effective, dimmable smart lighting solution

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Ultra-low power Bluetooth controlled, cost-effective, dimmable smart lighting solution [Copy link]

The Internet of Things is growing rapidly. In its sub-sectors, smart home and building automation applications, smart lighting plays a vital role in achieving energy conservation and power saving, reducing electricity costs, and making people's lives more convenient. To design a smart lighting solution with a competitive advantage, it is necessary to consider multiple aspects such as LED driver, communication, and energy efficiency.
　　The Internet of Things is growing rapidly. In its sub-sectors, smart home and building automation applications, smart lighting plays a vital role in achieving energy conservation and power saving, reducing electricity costs, and making people's lives more convenient. To design a smart lighting solution with a competitive advantage, it is necessary to consider multiple aspects such as LED driver, communication, and energy efficiency. ON Semiconductor provides smart lighting solutions based on Bluetooth low energy, integrating the scalable power linear LED AC direct driver NCL30170, the industry's lowest power Bluetooth 5 system-on-chip (SoC) RSL10 and the high-voltage linear regulator NCP786A, eliminating the switching power supply (SMPS), with an analog dimming range from 5% to 100%, a power factor (PF) of 0.99, and a total harmonic distortion (THDi) of only 11% under full load conditions. The standby power consumption is less than 200 mW, which helps designers to implement ultra-low power Bluetooth-controlled dimmable smart lighting solutions with high cost performance.
　

　　Figure 1: Bluetooth low energy smart lighting solution demonstration NCL30170 + RSL10 + NCP786A
　　how to drive smart dimming?
　　An obvious advantage of the AC direct drive topology is that it eliminates the traditional switching power supply, reduces the bill of materials (BoM) cost, reduces the board space, improves EMI performance, and makes the LED life longer.
　　ON Semiconductor's NCL30170 AC direct drive LED driver integrates a high-voltage startup current source to achieve fast startup for smart lighting and phase-cutting dimming applications. The controller manages the current of multiple LEDs in series and uses ON Semiconductor's proprietary auto-commutation topology to generate a smooth sine wave current, making the LED constant current accuracy reach ±1% and the THD less than 10%, thereby ensuring that the LED brightness remains unchanged and providing an industry-leading power factor (0.99).
　

　　Figure 2: NCL30170 achieves high-precision constant current
　　

　　Figure 3: NCL30170 provides excellent PF and THD
　　NCL30170 is also the first product on the market that can drive multiple external MOSFET switches to support the connection of multiple LED strings. The power can be extended from 5 W to 300 W. The total number of connected LED strings and external switches are only limited by the highest power level.
　　NCL30170 can achieve analog dimming with a dimming range from 5% to 100%, and can maintain voltage regulation throughout the dimming range, ensuring that the brightness of the LED remains unchanged even at low power. For phase-cut dimming using TRIAC, NCL30170 can achieve good thyristor compatibility.
　　In addition, NCL30170 also integrates protection features such as input overvoltage protection, Rcs short-circuit protection, and thermal shutdown to ensure high reliability.
　　Controlling smart lighting via Bluetooth low energy
　　RSL10 is a Bluetooth 5 certified radio system-on-chip that supports Bluetooth low energy and 2.4 GHz proprietary/custom protocols, with a data rate of 2 Mbps. It uses different packages to provide the industry's lowest Bluetooth power consumption for multi-field IoT applications, with a power consumption of only 62.5 nW in deep sleep mode and a peak reception power consumption of only 7 mW. Its high energy efficiency has been awarded the industry's highest EEMBC? ULPMark? score, and supports a wide power supply voltage range of 1.1 V to 3.3 V. It uses 384 kB flash memory, a dual-core processor (ARM Cortex-M3 processor, 32-bit Dual-Harvard DSP system), and supports the CEVA Bluetooth stack. In the absence of a high-voltage power supply, the RSL10 has a connection interval of 50 ms, providing a fast response when interacting with the user, with a peak current of 8 mA and an average current of only 42 ?A.
　

　　Figure 4: RSL10 block diagram
　　The adjustable output buck regulator
　　NCP786A is a high-performance high-voltage linear regulator with an input voltage range of 55 V to 450 VDC and an output current of 10 mA. The output voltage can be set by a resistor divider in the range of 1.27V to 15V, making it extremely suitable for high input voltage applications. It provides ultra-low quiescent current (typical value 10 ?A), ultra-high power supply rejection ratio (PSRR: 70 dB@60 Hz, 90 dB @100 kHz), self-consumption of no more than 25 ?A, and power consumption of only 8 mW, which is much lower than the commonly used switching power supply buck regulator.
　　Power consumption of RSL10 + NCP786A for dimming applications
　　At an input of 300 VDC, we measured the average current of the RSL10 + NCP786A dimmer to be 38 ?A when not connected, and the average current connected to be 57 ?A to 67 ?A, with a power consumption of only 22 mW.
　　

　　Figure 5: Dimmer Power Consumption – Vin 300 VDC
　　Standby Power Consumption The
　　measured standby power consumption (NCL30170 + RSL10) at 230 V AC input is about 140 mW to 150 mW, of which the NCL30170 consumes about 125 mW. The standby power consumption of the whole solution is less than 200 mW.
　　Summary
　　This Bluetooth low-power dimmable smart lighting solution adopts an innovative AC direct drive topology, without the need for traditional SMPS, and has advantages in cost, volume, service life and reliability. It can also flexibly expand the power range as needed. Based on ON Semiconductor's proprietary active constant power dimming control technology, the dimming range is from 5% to 100%, the power factor is 0.99, and the THDi at full power is only 11%. Even when dimming, it can maintain uniform lighting brightness. It integrates the industry's lowest power Bluetooth 5 SoC RSL10, providing advanced wireless functions without affecting system size. It provides ultra-high PSRR through the high-voltage linear regulator NCP786A, improves wireless application performance, and realizes high-performance, ultra-low power Bluetooth controlled dimmable smart lighting solutions with high cost performance.

华北小卿

After learning, if the solution is mature, it can be made into a central control system for smart homes