Segmented dimming / color matching led + constant current chip - two in one scheme

With the improvement of people's living standards and the strengthening of the diversified and personalized demand for lighting, consumers have higher and higher requirements for improving the home environment and comfort, which makes the lighting (dimming, color matching, etc.) with good experience more favored by many consumers. Therefore, yuejiahong Co., Ltd. focuses on customer needs and selects different lighting schemes for lighting applications in different scenes. Widely used in bulb, spotlight, downlight, filament lamp, lamp strip, light source module and other products.

1. Main advantages of the scheme

Three sections of brightness / color temperature change, sequence adjustable, LED current detection;

The periphery is simple, no chip capacitor is required, and the cost is low;

A single IC drives about 10W, and the switch switches the brightness / color temperature

Application scheme: with electrolysis (pf0.5), no stroboscopic, lamp bead voltage drop vf250-270v

2. Main features of the scheme:

The peripheral circuit is simple and does not need magnetic components

High power multi chip parallel application

The three color temperature sequences can be adjusted by external resistance

Constant current accuracy ± 5%

Built in overtemperature compensation

Adjust the brightness in sections, and the proportion can be set externally

Built in 550V high voltage MOS tube

The chip application system has no EMI problem

Three gear current detection dimming mode, dimming sequence is adjustable, and the minimum brightness is optional between 1% and 50%

Schematic diagram of color matching chip

3. Introduction to dimming and color matching functions:

By switching the switch once, the system detects the current on the chip sampling resistance. When the current on the chip sampling resistance is 0, the system will switch to the next state by default.

The voltage on the electrolytic capacitor is detected by the chip during the reset time of the system. When the electrolytic discharge voltage is lower than 6V, the chip returns to the initial state by default.

4. Examples of actual schemes:

Key performance indexes of lamp tube

Starting time 630uS

Output ripple 7mA

Application schematic diagram

reference resources DEMO