LED modules in which the complete drive electronics is included simplify the design of modern luminaires. Acrich 2 modules, made by Seoul Semiconductor, are available in different brightness levels and can be driven direct from the AC network without a ballast.

Acrich 2 modules from Seoul Semiconductor are designed for general illumination and are intended to be connected with 2 leads directly to the AC network without any further rectification needed. The incorporated IC, designed especially for the optimized drive of each individual LED, allows the lack of a separate ballast or rectifier. This space saving concept gives the designer a new freedom for the layout of his product.

Applications of the module start from modern luminaries to complex illumination systems but also conventional replacement bulbs and tubes. Benefits of the Acrich 2 are reduced weight, high life time, high efficacy and good power factor which gives tremendous long term potential for power savings in many illumination application.

Integrated driver concept
The drive circuit on the Acrich 2 modules consists of an IC generating the necessary current for each LED directly out of the AC without using a rectifier. Depending on power class the IC has 4 or 8 output channels which are directly connected to the LED. Each output channel is activated separately by the IC. The IC comprised all diodes and passive components and is therefore a simple and effective LED solution for the design of luminaries. As there is no need for life time limiting components like electrolytic capacitors the driver circuit does not limit lifetime. The AC synchronic drive of the LED reduces the noise level on the connection cables. In normal operation mode no further components are necessary to stay below the allowed noise level. This keeps the cost low. The human eye does not observe any flicker and many standard Dimmers can be used without problems. 

Image 1: Drive principle and current level in relation to the AC input Voltage

Image 1 shows the basic trigger circuit and the current level in dependence of the phasing AC voltage. For which LED the current is turned on from 0 to 180 shows the table below. 

Acrich IC is designed for the standard network voltages

The Acrich2-IC is available for AC drive voltages of 90 – 120V (100V) / 100 – 144V (120V) / 200 – 264V (220V / 230V / 240V) and a nominal output power of 4 and 8 Watt. Based on that product range the typical AC drive voltages all over the world can be addressed. Power factor is 90%, lifetime with a minimum of 87.000h. The max. junction temperature is specified with Tj = 125°C, operating temperature Topr -30 to 100°C and a storage temperature of Tstg -40 to 120°C. 

Image 2: Circuit configuration and mechanical appearance of the 4 Watt module (230V.)


Image 3: Circuit configuration and mechanical appearance of the 8 Watt module (230V). 
For full resolution click here.


Image 4: Circuit configuration and mechanical appearance of the of the 12 Watt module (230V). It consists of a 8 W and a 4 W circuit. 
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Image 2 – 4 show the electrical circuit and the mechanic appearance of the 4, 8 and 12 module (230V DC). Meanwhile a 16W module has been launched.