Three temperature zone linear constant power led drive integrated circuit

Abstract

The invention relates to a linear constant power LED driving integrated circuit with three temperature zones. The constant current driving circuit of the constant current driving circuit adjusts the power of driving the LED lamp bead according to the working current of the LED lamp bead, the reference voltage of near-zero temperature drift and the reference voltage of negative temperature. Make the power loaded by the constant current drive circuit on the LED bead match the working temperature of the LED bead; when the working temperature of the LED bead is close to the limit junction temperature of the LED bead, the junction temperature protection circuit is turned off The constant current drive circuit drives the LED lamp bead. In the present invention, the output power is basically unchanged before the low temperature reaches the temperature at which the LED lamp bead does not have light decay; when the temperature range of the LED lamp bead is above the temperature range where the light decay occurs, the power is reduced; when the LED lamp bead or the driving circuit reaches the limit junction temperature and is damaged Shutdown before, and can guarantee the reliability in high voltage or high voltage transient shock.

Description

technical field [0001] The invention relates to a driving integrated circuit, in particular to a linear constant power LED driving integrated circuit with three temperature zones, belonging to the technical field of LED driving circuits. Background technique [0002] At present, in the prior art, in order to solve the burning problem of LED lamp beads under high temperature, the scheme of linear constant current lighting power supply is often adopted. At high temperature, such as 115°C, the circuit performs temperature protection, and the driving current is rapidly attenuated or turned off at this time. But in fact, when the temperature of the LED lamp bead rises above 80°C, it has already begun to affect the light decay of the lamp bead. Therefore, the ideal lamp bead drive circuit should have the same driving power at low temperature or room temperature, but at a high temperature such as 80°C Start slow power decay to reduce the operating temperature, and when the temperat...

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Problems solved by technology

[0003] In addition, the linear constant current LED drive circuit usually increases the output power when the input voltage increases, it is difficult to ensure that the LED drive circuit works in a constant power state

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