Dimmable intelligent lighting solution based on an ultra-low power Bluetooth control

The Internet of Things is growing at a high speed. In its segmented areas of smart home and building automation applications, intelligent lighting plays a pivotal role in achieving energy saving, reducing electricity costs, and facilitating people's lives. To design a smart lighting solution with competitive advantages, it is necessary to consider LED driving, communication, energy efficiency and so on. ON Semiconductor offers intelligent lighting solutions based on Bluetooth low energy, integrated linear LED AC direct drive NCL30170 with scalable power, industry's lowest power Bluetooth 5 system single-chip (SoC) RSL10 and high voltage linear regulator NCP786A, eliminating Switching Power Supply (SMPS) with analog dimming range from 5% to 100%, power factor (PF) of 0.99, total harmonic distortion (THDi) at full load is only 11%, and standby power consumption is less than 200 mW. A dimmable intelligent lighting solution that enables designers to achieve ultra-low power Bluetooth control at a cost-effective price.

Figure 1: Bluetooth Low Energy Smart Lighting Solution Demo NCL30170 + RSL10 + NCP786A

How to drive smart dimming?

A significant advantage of AC direct drive topologies is the elimination of traditional switching power supplies, reduced bill of materials (BoM) costs, reduced board space, improved EMI performance, and longer LED life.

ON Semiconductor's NCL30170 AC direct drive LED driver integrates a high-voltage start-up current source for fast start-up for intelligent lighting and phase-cut dimming applications. The controller manages multiple LED currents in series, using ON Semiconductor's proprietary Auto-commutation topology produces smooth sinusoidal currents with constant current accuracy of ±1% and THD of less than 10%, ensuring LED brightness remains constant and providing industry-leading power factor (0.99) .

Figure 2: NCL30170 achieves high precision constant current

Figure 3: The NCL30170 provides excellent PF and THD

The NCL30170 is also the first product on the market to drive multiple external MOSFET switches to support the connection of multiple LED strings. Power can be extended from 5 W to 300 W. The total number of connected LED strings and external switches are limited only by the highest power levels.

The NCL30170 is capable of analog dimming with a dimming range from 5% to 100% and maintains regulation over the entire dimming range, ensuring that the brightness of the slave LED remains constant even at low power. For phase-cut dimming with TRIAC, the NCL30170 achieves good thyristor compatibility.

In addition, the NCL30170 integrates input overvoltage protection, Rcs short-circuit protection, thermal shutdown and other protection features to ensure high reliability.

Control intelligent lighting with Bluetooth low energy

The RSL10 is a Bluetooth 5 certified radio system single chip that supports Bluetooth low energy and 2.4 GHz proprietary/custom protocols with data rates up to 2 Mbps. It offers the industry's lowest Bluetooth power consumption for deep ICT applications in a variety of IoT applications. With only 62.5 nW of power consumption and only 7 mW of peak receive power, it is the industry's highest EEMBC® ULPMarkTM score for energy efficiency and supports a wide supply voltage range of 1.1 V to 3.3 V with 384 kB flash and dual-core processors. (ARM Cortex-M3 processor, 32-bit Dual-Harvard DSP system), also supports CEVA Bluetooth stack. With no high-voltage power supply, the RSL10 has a connecTIon interval of 50 ms, providing fast response when interacting with the user, with a peak current of 8 mA and an average current of only 42 μA.

Figure 4: RSL10 block diagram

Adjustable output buck regulator

The 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 from 1.27V to 15V, making it ideal for high input voltages. application. Provides ultra-low quiescent current (typically 10 μA), ultra-high power supply rejection ratio (PSRR: 70 [email protected] Hz, 90 [email protected] kHz), self-consumption power not exceeding 25 μA, and power consumption is only 8 mW, much lower than A commonly used switching power supply buck regulator.

RSL10 + NCP786A for power consumption in dimming applications

At 300 VDC input, we measured the RSL10 + NCP786A dimmer with an average current of 38 μA when unconnected, an average current of 57 μA to 67 μA, and a power consumption of only 22 mW.

Figure 5: Dimmer power consumption – Vin 300 VDC

Standby power consumption

The standby power consumption (NCL30170 + RSL10) measured at 230 V AC input is approximately 140 mW to 150 mW, of which the NCL30170 consumes approximately 125 mW. The standby power consumption of the entire solution is less than 200 mW.

to sum up

The Bluetooth low-power dimmable smart lighting solution features an innovative AC direct drive topology that eliminates the need for traditional SMPS and offers cost, size, longevity and reliability advantages, and the ability to flexibly extend the power range as needed, based on Anson US Semiconductor's proprietary active constant power dimming control technology, dimming range from 5% to 100%, power factor of 0.99, THDi at full power is only 11%, even to maintain uniform illumination even when dimming Integrates the industry's lowest power Bluetooth 5 SoC RSL10, providing advanced wireless capabilities without compromising system size. High-voltage linear regulator NCP786A provides ultra-high PSRR, improves wireless application performance, and achieves high performance and ultra-low power with high cost performance. A dimmable intelligent lighting solution that consumes Bluetooth control.