Electronic converter and related lighting system
An electronic converter, including a measurement circuit for determining a first signal indicative of the voltage or current supplied by the electronic converter, a regulation circuit for generating a regulation signal as a function of the first signal and one or more reference signals, and a driver circuit for driving the switching stage of the electronic converter as a function of the regulation signal. The electronic converter includes an optical, inductive or capacitive coupler and a transmission circuit configured to generate a pulse width modulated signal applied to the input of the optical, inductive or capacitive coupler, wherein the transmission circuit varies the duty cycle and the frequency of the pulse width modulated signal as a function of the first and second signal. The electronic converter includes a receiver circuit configured to monitor the received signal at the output of the optical, inductive or capacitive coupler.
1. An electronic converter comprising:
two input terminals for receiving an input voltage;
two output terminals for providing a DC voltage or a DC current;
a transformer comprising a primary winding and a secondary winding;
a switching stage configured to selectively transfer energy from the two input terminals to the primary winding of the transformer;
a rectification and filter circuit connected between the secondary winding of the transformer and the two output terminals;
a measurement circuit configured to determine a first signal indicative of the DC voltage or the DC current provided via the output terminals;
a regulation circuit configured to generate a regulation signal as a function of the first signal and one or more reference signals;
a driver circuit configured to drive the switching stage as a function of the regulation signal;
wherein the electronic converter comprises:
an optical, inductive or capacitive coupler;
a transmission circuit configured to generate a pulse width modulated signal applied to the input of the optical, inductive or capacitive coupler, wherein the transmission circuit is configured to vary the duty cycle and the frequency of the pulse width modulated signal as a function of the first signal and a second signal; and
a receiver circuit configured to monitor the received signal at the output of the optical, inductive or capacitive coupler, the receiver circuit comprising:
a first low-pass or band-pass filter circuit configured to generate a third signal indicative of the duty cycle of the received signal by a low-pass or band-pass filtering of the received signal; and
a pulse-generating circuit configured to generate a pulsed signal, wherein the pulse-generating circuit is configured to generate a pulse with a fixed duration in response to a rising edge and/or a falling edge of the received signal, and
a second low-pass or band-pass filter circuit configured to generate a fourth signal by a filtering of the pulsed signal, whereby the fourth signal is indicative of the frequency of the received signal.
2. The electronic converter according to claim 1 , wherein the transmission circuit is configured to vary the duty cycle of the pulse width modulated signal as a function of the first signal and the frequency of the pulse width modulated signal as a function of the second signal, such that the third signal is indicative of the first signal and the fourth signal is indicative of the second signal.
3. The electronic converter according to claim 1 , wherein the pulse-generating circuit configured to generate a pulsed signal is implemented with a monostable.
4. The electronic converter according to claim 1 , wherein the converter is adapted to power a lighting module via the two output terminals, and wherein the second signal is provided by:
a sensor configured to detect the type and/or the operation state of the lighting module; and/or
a light sensor configured to detect the ambient luminosity or the luminosity of the light emitted by the lighting module; and/or the color of the light emitted by the lighting module; and/or
a temperature sensor configured to detect a temperature of the electronic converter and/or a temperature of the lighting module; and/or
a sensor of other environmental data, such as the ambient temperature.
5. The electronic converter according to claim 1 , wherein one of the one or more reference signals corresponds to the fourth signal.
6. The electronic converter according to claim 1 , wherein the first signal is indicative of the DC current and the second signal is indicative of a maximum current.
7. The electronic converter according to claim 1 , wherein the electronic converter comprises a reference generating circuit configured to generate one or more of the reference signals as a function of:
the fourth signal, and
a further signal provided by the driver circuit, a sensor and/or a receiver, and/or received via a further terminal of the electronic converter.
8. The electronic converter according to claim 7 , wherein the first signal is indicative of the DC current, the second signal is indicative of a maximum current, and the further signal corresponds to a dimming signal.
9. The electronic converter according to claim 6 , wherein the regulation circuit is arranged on the primary side of the electronic converter and comprises:
a PI or PID regulator configured to generate the regulation signal by comparing the first signal with a reference signal;
a comparator with hysteresis configured to generate the regulation signal by comparing the first signal with a reference signal;
a comparison circuit configured to generate the regulation signal by comparing the first signal with a first reference signal indicative of a lower threshold and with a second reference signal indicative of an upper threshold.
10. The electronic converter according to claim 1 , wherein the first low-pass or band-pass filter circuit comprises an RC filter comprising a first resistor and a first capacitor.
11. The electronic converter according to claim 1 , wherein the second low-pass or band-pass filter circuit comprises an RC filter comprising a second resistor and a second capacitor.
12. A lighting system comprising a lighting module and an electronic converter comprising:
two input terminals for receiving an input voltage;
two output terminals for providing a DC voltage or a DC current;
a transformer comprising a primary winding and a secondary winding;
a switching stage configured to selectively transfer energy from the two input terminals to the primary winding of the transformer;
a rectification and filter circuit connected between the secondary winding of the transformer and the two output terminals;
a measurement circuit configured to determine a first signal indicative of the DC voltage or the DC current provided via the output terminals;
a regulation circuit configured to generate a regulation signal as a function of the first signal and one or more reference signals;
a driver circuit configured to drive the switching stage as a function of the regulation signal;
wherein the electronic converter comprises:
an optical, inductive or capacitive coupler;
a transmission circuit configured to generate a pulse width modulated signal applied to the input of the optical, inductive or capacitive coupler, wherein the transmission circuit is configured to vary the duty cycle and the frequency of the pulse width modulated signal as a function of the first signal and a second signal; and
a receiver circuit configured to monitor the received signal at the output of the optical, inductive or capacitive coupler, the receiver circuit comprising:
a first low-pass or band-pass filter circuit configured to generate a third signal indicative of the duty cycle of the received signal by a low-pass or band-pass filtering of the received signal;
a pulse-generating circuit configured to generate a pulsed signal, wherein the pulse-generating circuit is configured to generate a pulse with a fixed duration in response to a rising edge and/or a falling edge of the received signal, and
a second low-pass or band-pass filter circuit configured to generate a fourth signal by a filtering of the pulsed signal, whereby the fourth signal is indicative of the frequency of the received signal.