- #1
Scott Black
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Hey all,
Im working on making a signal converter for a mod I've done on my car,
the plans for it are from zilvia.net - 164351-s15-cluster-sig-converter (edit: link was not working and apparently triggered spam detector)
yet I've been looking around a lot of places and can't find the lm340H-5 and lm340H-12 (or the lm140 it says could be used instead)
I have however found a place i can get lm340T-5 and lm340T-12
what I am wondering is can i use those regulators instead of the ones the schematics asks for?
thanks
Scott
ive copyed the info from the other thread that the link won't work to below
Here is the part list:
Part Value
C1 0.01U
C2 0.01U
C2A 1U
C2B 1U
C3 0.1U
C4 1U
C5 0.1U
C6 0.22U
C7 0.22U
C8 0.1U
C9 0.1U
IC1 LM340H-05 or LM140A-05
IC2 LM340H-12 or LM140A-12
IC3 74LS109N
IC4 LM331N
IC5 LM2917
R1 100K
R2 10K
R3 100K
R4 470
R5 100K
R6 47
R7 6.8K
R8 10K
R9 6.8K
R10 5K
All resistors are 5% or less and all the caps are ceramic or tantalum.
This is needed to keep the temp coef down. It can get hot under the dash.
Now let's get into what everything does.
-Power and logic levels-
IC1 and IC2 are the volatge regulators. IC2, C7 and C8 regulate the input voltage
to 12v which is used for power to the LM2917 and LM331. IC1,C6 and C5 then regulate
that to 5v for logic high and power for the 74LS109N.
-Input frequency to voltage converter-
IC5, R1, R2, R4, C9, C1, C2A, C2B are used to convert the speedo input from a
zero crossing signwave to a voltage.
C9 is a filter for the input since its really noisy. R4 is for voltage dropping
sice the LM2917 has a 7.6v internal zener regulator.
The output voltage is defined by Vout = Vcc * Fin * C1 * R1 * K
where K = 1 and VCC = 7.6
The output ripple is defined by Vripp = (Vcc / 2) * (C1/(C2A+C2B)) * (1 - ((Vcc * Fin * C1) / I3))
where VCC = 7.6, I3 = 180uA, Fin = input freq 4.5hz(1mph) - 810hz(180mph)
-Voltage to frequency converter primary-
IC4, R3, C3, C4, R5, R6, R7, C2, R9, R10 are used to convert the voltage back to a frequency.
That frequency is defined by Fout = (Vin/2.09) * ((R9+R10)/R5) * (1/ (R7 * C2))
Where Vin = Vout from the F-to-V converter.
R10 is adjustable so the conversion factor can be fully adjusted.
R6 and C4 are used to keep the internal referance stable.
R3 and C3 are for input filtering.
-Signal conditioning-
IC3 and R8 are used to form the 50% duty cycle square wave. IC3 is a dual J/K
flip flop so the output will change its state once per pulse and dividing the
primary output freq by 2. This is needed because the output pulse width from the LM331
is too small.
Output here should be 12.5hz/mph
Im working on making a signal converter for a mod I've done on my car,
the plans for it are from zilvia.net - 164351-s15-cluster-sig-converter (edit: link was not working and apparently triggered spam detector)
yet I've been looking around a lot of places and can't find the lm340H-5 and lm340H-12 (or the lm140 it says could be used instead)
I have however found a place i can get lm340T-5 and lm340T-12
what I am wondering is can i use those regulators instead of the ones the schematics asks for?
thanks
Scott
ive copyed the info from the other thread that the link won't work to below
Here is the part list:
Part Value
C1 0.01U
C2 0.01U
C2A 1U
C2B 1U
C3 0.1U
C4 1U
C5 0.1U
C6 0.22U
C7 0.22U
C8 0.1U
C9 0.1U
IC1 LM340H-05 or LM140A-05
IC2 LM340H-12 or LM140A-12
IC3 74LS109N
IC4 LM331N
IC5 LM2917
R1 100K
R2 10K
R3 100K
R4 470
R5 100K
R6 47
R7 6.8K
R8 10K
R9 6.8K
R10 5K
All resistors are 5% or less and all the caps are ceramic or tantalum.
This is needed to keep the temp coef down. It can get hot under the dash.
Now let's get into what everything does.
-Power and logic levels-
IC1 and IC2 are the volatge regulators. IC2, C7 and C8 regulate the input voltage
to 12v which is used for power to the LM2917 and LM331. IC1,C6 and C5 then regulate
that to 5v for logic high and power for the 74LS109N.
-Input frequency to voltage converter-
IC5, R1, R2, R4, C9, C1, C2A, C2B are used to convert the speedo input from a
zero crossing signwave to a voltage.
C9 is a filter for the input since its really noisy. R4 is for voltage dropping
sice the LM2917 has a 7.6v internal zener regulator.
The output voltage is defined by Vout = Vcc * Fin * C1 * R1 * K
where K = 1 and VCC = 7.6
The output ripple is defined by Vripp = (Vcc / 2) * (C1/(C2A+C2B)) * (1 - ((Vcc * Fin * C1) / I3))
where VCC = 7.6, I3 = 180uA, Fin = input freq 4.5hz(1mph) - 810hz(180mph)
-Voltage to frequency converter primary-
IC4, R3, C3, C4, R5, R6, R7, C2, R9, R10 are used to convert the voltage back to a frequency.
That frequency is defined by Fout = (Vin/2.09) * ((R9+R10)/R5) * (1/ (R7 * C2))
Where Vin = Vout from the F-to-V converter.
R10 is adjustable so the conversion factor can be fully adjusted.
R6 and C4 are used to keep the internal referance stable.
R3 and C3 are for input filtering.
-Signal conditioning-
IC3 and R8 are used to form the 50% duty cycle square wave. IC3 is a dual J/K
flip flop so the output will change its state once per pulse and dividing the
primary output freq by 2. This is needed because the output pulse width from the LM331
is too small.
Output here should be 12.5hz/mph
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