RMI-FC100, a single stage audio power amplifier

i can see in "rmi-fc100.zip" file that the pcb board of the amplifier is not completely finished ... do You have a completed board file in Eagle/Corel/*.jpg.... thanks....

:)


also You have said that it is 90W/8ohm amplifier - it seems to me that it is a bit to much when we look at power supply voltage (but i am not an expert) - is there an error in typing related power or is it really 90W amp???

nice boards btw.
 
sparkle said:
i can see in "rmi-fc100.zip" file that the pcb board of the amplifier is not completely finished ... do You have a completed board file in Eagle/Corel/*.jpg.... thanks....

:)


also You have said that it is 90W/8ohm amplifier - it seems to me that it is a bit to much when we look at power supply voltage (but i am not an expert) - is there an error in typing related power or is it really 90W amp???

nice boards btw.

Sparkle,

The Eagle board is finished. You have to generate planes by pressing "Ratsnets" button.
Regarding power, it depends on suppply voltage. A it is now on published schematics, it is rated at 6ohm speaker impedance (monitor audio gold GS20) and not at 8 ohm.
The ampplifier, for Zout 6ohm, is SOA underpowered and can generate much more power if you don't care about class A dissipation.

Mihai
 
Mihai - you are my hero - now i have learned something new related Eagle.... perfect really..... thank You - i am happy as a morning bird..... :)
thank You....

related power---- so what is an optimum power supply voltage for best performance in your opinion and how much power i will get out of the amp - i have speakers that are 4-6ohm impedance (not really sure right now).....

thanks again
 
one more....
2s5200/2sa1943 - can they be used in Your design without altering the schematic?
(pinout is different - but regarding the sound and the behaviour of the amp would it be problematic to use those transistors)...

if so... i am thinking - maybe to use those transistors and to use maybe soem TO220 diodes and to connect them to the heatsink and between eachother as in the schematic...or simply to use vbe multiplier.... how about that... i do not have those nice njl transistors - they are hard to find here...but i have c5200 and a1943 more than enough....

any opinions ?

thanks for any reply.....
 
Behind the excelent designer, there's an excelent daddy, a family man

that has a charming face, a kind expression and offering to be friend and to help me to construct his design.

I feel proud to have someone so good as Mihai is helping me.

He told me to substitute the LEDs into the simulator, by voltage sources...Fine!...he found solution to my problem

Clever folk.... i had not that idea.

Image is from Mihai and his wife Ioana...picture made in June of this year.

regards,

Carlos
 

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i have a question.....
i have found LED diodes on RS components catalogue....
red diode is L-383HDT - 2V/5mA (no. in catalogue 247-1274) and green one is L-383GDT 1.96V/5mA (no. in catalogue 247-1296)..........
would they be suitable....

one more question.... how is this amp behaving when driving "heavy" speakers.......
 
Sparkle,

Regarding Light Emitting Diode, you could use any type you can find as long as the shape is rectangular, 2.5x5mm, and forward biased voltage is in the range of 1.96V to 2.1V. Try to not use very bright LEDs.
Buy 10-15 pieces and put all of them in series with a current limiter resistor, then bias all string at 5...6mA (see ASCII figure below).

(+30..40V)--|>||----|>||----|>||-- ... --|>||----|>||--[===]--(GND)

Measure forward voltage for all LEDs and match them two by two for left and right channel LTP and cascode current sources.

Mihai
 
roender said:
Sparkle,

Regarding Light Emitting Diode, you could use any type you can find as long as the shape is rectangular, 2.5x5mm, and forward biased voltage is in the range of 1.96V to 2.1V. Try to not use very bright LEDs.
Buy 10-15 pieces and put all of them in series with a current limiter resistor, then bias all string at 5...6mA (see ASCII figure below).

(+30..40V)--|>||----|>||----|>||-- ... --|>||----|>||--[===]--(GND)

Measure forward voltage for all LEDs and match them two by two for left and right channel LTP and cascode current sources.

Mihai


that is what i have had in my mind :) thanks for info :)