Opto-Electronics


Linear LED drivers

2 May 2012 Opto-Electronics

Supertex has introduced CL8800 and CL8801 – sequential, linear LED drivers designed to drive long strings of low-cost, low-current LEDs in solid-state replacements for fluorescent tubes, incandescent bulbs and CFL bulbs.

Both ICs minimise driver circuit component counts, requiring just four or six resistors and a diode bridge in addition to the IC. Two to four additional components in the circuit provide transient protection, and neither capacitors nor magnetic components are required. Because the ICs are multi-stage linear current regulators, there are no high-frequency switching currents and, thus, no need for a front-end EMI filter.

The CL8800 is intended for 230 V a.c. input, while the CL8801 is for 120 V a.c. input. Luminous efficiencies of greater than 115 lm/W are achievable with both ICs. The CL8800 has six current regulator outputs while the CL8801 has four. These outputs tap a string of series parallel LEDs, and the regulators sink current at each tap and are sequentially turned on and off automatically, tracking the input sine wave voltage.

Voltage across each regulator is minimised when conducting, providing typical efficiency of greater than 90%. Output current at each tap is individually resistor-adjustable. Cross regulation, as the IC switches from one regulator to another, provides smooth transitions.

The current waveforms of both ICs can be tailored to optimise for input voltage range, line/load regulation, output power/current, efficiency, power factor, THD, dimmer compatibility and LED utilisation. Both ICs are compatible with phase dimming with the addition of an RC network.



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

VentoFlex modular LED lighting system
23 October 2019, Mimic Components , Opto-Electronics
Visual Communications Company (VCC) launched its VentoFlex flexible modular lighting system. The system is made up of flexible copper clad laminate (FCCL) sheets with 90 CRI Luxeon LEDs. VentoFlex was ...

Read more...
LED flicker, and how to prevent it
28 August 2019, Avnet South Africa , Opto-Electronics
With the growing popularity of LED lighting, especially now that very cheap LED luminaires are coming to the market, flicker is becoming more of a problem. Flicker, a repetitive switching on and off ...

Read more...
Digital fibre-optic sensor
28 August 2019, Vepac Electronics , Opto-Electronics
The DFS digital fibre-optic sensor series from Tri-Tronics is designed to provide reliable detection using plastic fibre-optic light guides. The slim-line housing with protective lid will fit in a variety ...

Read more...
All-in-one light pipe system
28 August 2019, Vepac Electronics , Opto-Electronics
Bivar’s Zero Light Bleed adaptor technology, with built-in surface-mount LED, channels light directly to the lens, eliminating disruptive light bleed. The all-in-one adaptor system is built with optimum ...

Read more...
High-intensity colour LEDs
31 July 2019, Würth Elektronik eiSos , Opto-Electronics
Würth Elektronik has expanded its LED portfolio with a particularly compact model family. The WL-SMCC series of SMT chip LEDs, available in 0402 and 0603 packages, is characterised by a full-surface lens ...

Read more...
RGB LEDs for decorative lighting
26 June 2019, Würth Elektronik eiSos , Opto-Electronics
Würth Elektronik’s new WL-SFTW and WL-SFTD series of RGB LEDs are targeted at accent and decorative lighting, optical displays as well as industrial applications. Thanks to their PLCC contacting design, ...

Read more...
4,3” TFT LCD module
26 June 2019, iCorp Technologies , Opto-Electronics
The RFE430W-AYW-DNN from Raystar is a 4,3” TFT display with a resolution of 480 x 270 pixels. It has a built-in SC7283 driver IC and supports an RGB 24-bit interface, with brightness of 500 nits, an aspect ...

Read more...
High-intensity colour LEDs
26 June 2019, Würth Elektronik eiSos , Opto-Electronics
Würth Elektronik has expanded its LED portfolio with a particularly compact model family. The WL-SMCC series of SMT chip LEDs, available in 0402 and 0603 packages, is characterised by a full-surface lens ...

Read more...
LEDs recognised for achieving natural light spectrum
29 May 2019, NuVision Electronics , Opto-Electronics
Seoul Semiconductor’s SunLike range of natural spectrum LEDs, first announced in 2017, have gone on to be recognised as an innovative technology for human-centric lighting at global lighting awards held ...

Read more...
Infrared detectors
29 May 2019, Würth Elektronik eiSos , Opto-Electronics
Würth Elektronik eiSos is expanding its optoelectronics portfolio. Following infrared LEDs, the company now also offers a wide range of matching detectors. Developers of various infrared applications ...

Read more...