Privacy statement: Your privacy is very important to Us. Our company promises not to disclose your personal information to any external company with out your explicit permission.
This LED lamp uses only three transistors, and only needs 0.71V voltage to start LED illumination. A 5th alkaline battery can be used to continuously illuminate the lamp for 170 hours, which greatly improves the battery utilization.
The power supply voltage of the LED lamp is set according to the voltage range of the alkaline battery of No. 5 from 0.9V to 1.7V. Figure 1 shows the measured battery power supply. This circuit can operate to a 0.71V supply voltage.
The circuit is shown in Figure 2. The forward current of the LED follows the supply voltage change. The transistors Tr1, Tr2 form a current mirror circuit to stabilize the bias (DC operating point). During the turn-off of Tr3, the bases of Tr1 and Tr2 are slightly reversed, and no current flows through R1. As a result, the circuit can oscillate stably over a wide temperature range and battery voltage, as well as the error range of the components. Fig. 3 is a collector voltage waveform of Tr1.
The DC resistance of the inductor L1 in Figure 2 is 4Ω. Its large resistance limits the current when Tr3 or LED is shorted.
October 22, 2024
October 21, 2024
On April 22, network activity named "FAST 2015 -! OPEN DAY" was launched by a brand LED high-power outdoor lighting manufacturer- Shenzhen Lead Optoelectronics Technology Co., Ltd.(Chinese name is...
Recently, the world's leading watch brand Hublot and brand ambassador, legendary track and field athlete Usain Bolt hand in hand into Kyoto, the ancient capital of Japan, with passion to ignite...
This article is reproduced, does not represent the world position of million table.
After two years of breakthrough in the laboratory's light efficiency of 200 lm/W, Cree has finally produced the series of LED chips with 200 lumens per watt at the end of 2012, and officially...
Email to this supplier
October 22, 2024
October 21, 2024
Privacy statement: Your privacy is very important to Us. Our company promises not to disclose your personal information to any external company with out your explicit permission.
Fill in more information so that we can get in touch with you faster
Privacy statement: Your privacy is very important to Us. Our company promises not to disclose your personal information to any external company with out your explicit permission.