Hi,
I hope to start a discussion if single chip class-D amps needs DC speaker protection with relay's when designing products for paying customers.
Almost all class-A and class-AB amps are being designed with DC speaker protection relays, but when I look at class-D finished commercial product, many have no relays.
This is probably only for cost reasons. Many are bridge designs, DC speaker relay protection needs more components and space for bridged amps.
Some IC vendors claim their internal protection also protects the speakers, but this seems to me unlikely to be full proof.
As recent single chip amps become high quality and powerful it's now more likely expensive speakers will be used. Would be bad if your amp fries your customer's $10k speakers...
On the other side, adding 2 relays & related electronics almost doubles the PCB area in many designs.
Any thoughts? Any experience with class-D single chip amps failing and putting DC out?
I hope to start a discussion if single chip class-D amps needs DC speaker protection with relay's when designing products for paying customers.
Almost all class-A and class-AB amps are being designed with DC speaker protection relays, but when I look at class-D finished commercial product, many have no relays.
This is probably only for cost reasons. Many are bridge designs, DC speaker relay protection needs more components and space for bridged amps.
Some IC vendors claim their internal protection also protects the speakers, but this seems to me unlikely to be full proof.
As recent single chip amps become high quality and powerful it's now more likely expensive speakers will be used. Would be bad if your amp fries your customer's $10k speakers...
On the other side, adding 2 relays & related electronics almost doubles the PCB area in many designs.
Any thoughts? Any experience with class-D single chip amps failing and putting DC out?