Navajo
With Diamond Lateral MOSFET output stage.
THD 0.000044% at 1 Watt
16 Watt output with low distortion
With Diamond Lateral MOSFET output stage.
THD 0.000044% at 1 Watt
16 Watt output with low distortion
Last edited:
First time I've seen a amplifier/electronic circuit named after a Native American tribe.
The Navajo (Dine) people live in the Four Corners area of the USA. It is the largest tribe in the USA.
Very good THD, but I would have expected more power output for an amplifier named after the biggest Native American tribe in the USA?
The Navajo (Dine) people live in the Four Corners area of the USA. It is the largest tribe in the USA.
Very good THD, but I would have expected more power output for an amplifier named after the biggest Native American tribe in the USA?
Hi lineup,
I'm not very familiar with diamond topologies. What is the gained (or lost) in the OPS by using drivers in a diamond configuration versus the more traditional EF?
I'm not very familiar with diamond topologies. What is the gained (or lost) in the OPS by using drivers in a diamond configuration versus the more traditional EF?
In a typical diamond buffer, U3,U4 compensate the temperature coefficient of U7 and U8. No bias generator needed. This only works well if all transistors are of same type BJT / MOS and thermally coupled.
Also, dependent on circuit details, a diamond buffer may swing closer to the rails than an emitter follower.
Also, dependent on circuit details, a diamond buffer may swing closer to the rails than an emitter follower.
So in this case, what is gained? Lateral MOSFETs generally don't have issues with temperature stability. And the devices in the diamond are of different types.
Is it just the better efficiency by swinging closer to the rails?
I tried this in LTspice and it seems pretty good 👍 but it does need an output inductor/Zobel to maintain stability (as do most designs). Small capacitive loads cause instability.
This is at 1 watt and 213ma bias current. The results agree very closely with @lineup
View attachment 1342953
Might be worth looking at the slew rates. This is 20kHz.... and I think you have edited post #1 with different values on the diagram...
Giving:
This is at 1 watt and 213ma bias current. The results agree very closely with @lineup
View attachment 1342953
Might be worth looking at the slew rates. This is 20kHz.... and I think you have edited post #1 with different values on the diagram...
Giving:
Damn, that's some high distortion 😆 Though I don't know about biasing the output devices with resistors alone. What would happen if bootstrap caps were added to R15 and R16?
Probably OK with lateral MOSFETs. Many designs with laterals use just resistors since their tempco becomes positive around 125mA of bias.
There are many native american tribes.
I have decided to name my amplifiers after them 🙂
Thanks for the work of @Mooly
Yes I should add Zobel at the output and a low pass filter at the input.
Basic diamond could be significantly improved (attachment).
Plus a big capacitor ( https://www.tubecad.com/2022/06/blog0558.htm ):
These will give results.
Plus a big capacitor ( https://www.tubecad.com/2022/06/blog0558.htm ):
These will give results.