High cost performance of ultra low power Bluetooth control

Release on : Jul 15, 2019

Ultra-low-power Bluetooth control cost-effective dimmable intelligent lighting solution


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), analog dimming range from 5% to 100%, power factor (PF) up to 0.99, total harmonic distortion (THDi) at full load conditions is only 11%, standby power consumption is less than 200mW, help The designer implements a dimmable intelligent lighting solution with 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 5W to 300W, and 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 and deep sleep mode for multi-domain IoT applications in different packages. With a power consumption of only 62.5nW and a peak receive power consumption of only 7mW, it is the industry's highest EEMBC® ULPMarkTM score, supports a wide supply voltage range of 1.1V to 3.3V, and uses 384kB flash memory for dual-core processors (ARM Cortex) -M3 processor, 32-bit Dual-Harvard DSP system), also supports CEVA Bluetooth stack. In the absence of high-voltage power, the RSL10 connection interval is 50ms, providing fast response when interacting with the user, with a peak current of 8mA and an average current of only 42μA.


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 55V to 450VDC and an output current of 10mA. The output voltage can be set by a resistor divider from 1.27V to 15V, making it ideal for high input voltage applications. Provides ultra-low quiescent current (typically 10μA), ultra-high power supply rejection ratio (PSRR: 70dB@60Hz, 90dB@100kHz), self-consumption power does not exceed 25μA, power consumption is only 8mW, much lower than the commonly used switching power supply Stabilizer.


RSL10+NCP786A for power consumption in dimming applications


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


Figure 5: Dimmer Power Consumption – Vin 300 VDC


Standby power consumption


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


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. Any electronic components you need can be purchased at https://www.barumelec.com/