Frequency generator perfect waves till 1 mhz, 1 till 10 FET channels
#2 · date not recorded
Stevie,
The circuit you posted above is not properly implementing the VCO section of the 4046. By definition the oscillator is Voltage Controlled, yet the control signal is missing and the VCOIN pin 9 is left floating. Also, R2 (pin 12) is not being used. This means the user could adjust the frequency down to 0 hz, causing full current DC across the load. This will likely smoke a transformer.
When the 4046 VCO is implement properly, R1 and C1 set the range and center frequency. R2 sets the offset. Then a voltage at VCO IN (Pin 9) controls the frequency in the ICs linear range. This voltage will be from about . 5 Vdc to about 4.2 Vdc assuming a 5 V Vdd supply .
The output will then be a 50 percent duty cycle square wave from Fmin to Fmax (as set by C1, R1, and R2)
where ... .5v at VCO IN = Fmin Out and 4.2V at VCO IN = Fmax Out . R1 should not be used to control frequency, but rather to set the center frequency / range. Again I am assuming a VDD of 5V.
I would attach a schematic of an actual working circuit of a properly implemented 4046, but I cant see how to do that here. ( Thanks for the tip - file is attached now)
The NTE4046B is an overpriced replacement version of the CD4046. The 74HC4046 is a somewhat updated version with a better a PLL section and higher frequency capability. Both the 74HC4046 and the CD4046 are still available through Mouser for less than $1 each. The NTE4046 lists for over $3.50 each. NTE parts many times do not perform to spec. NTE does not even publish a Data Sheet for their 4046. Personally, I would avoid the NTE version. Texas Instruments still makes this somewhat obsolete CD4046 IC. These will probably be discontinued soon like many of the older logic series IC's.
Meyer could not have used an NTE4046 since NTE did not make a 4046 in 1985. Meyer probably used a National Semiconductor or ST Micro version of the 4046.
Stevie, you may want to double check your stated "400ma" output specification. These are low power devices designed to clock CMOS logic. 2- 4 ma would be about max. At 12 Volts out and 400ma that would be about 2.4 watts at 50 % duty cycle. Not likely to happen without some smoke since this chip can only dissipate 500mw max.
Another interesting IC is the older 74LS629. This is a dual VCO Chip ( NO PLL) good to about 20 mhz.
The circuit you posted above is not properly implementing the VCO section of the 4046. By definition the oscillator is Voltage Controlled, yet the control signal is missing and the VCOIN pin 9 is left floating. Also, R2 (pin 12) is not being used. This means the user could adjust the frequency down to 0 hz, causing full current DC across the load. This will likely smoke a transformer.
When the 4046 VCO is implement properly, R1 and C1 set the range and center frequency. R2 sets the offset. Then a voltage at VCO IN (Pin 9) controls the frequency in the ICs linear range. This voltage will be from about . 5 Vdc to about 4.2 Vdc assuming a 5 V Vdd supply .
The output will then be a 50 percent duty cycle square wave from Fmin to Fmax (as set by C1, R1, and R2)
where ... .5v at VCO IN = Fmin Out and 4.2V at VCO IN = Fmax Out . R1 should not be used to control frequency, but rather to set the center frequency / range. Again I am assuming a VDD of 5V.
I would attach a schematic of an actual working circuit of a properly implemented 4046, but I cant see how to do that here. ( Thanks for the tip - file is attached now)
The NTE4046B is an overpriced replacement version of the CD4046. The 74HC4046 is a somewhat updated version with a better a PLL section and higher frequency capability. Both the 74HC4046 and the CD4046 are still available through Mouser for less than $1 each. The NTE4046 lists for over $3.50 each. NTE parts many times do not perform to spec. NTE does not even publish a Data Sheet for their 4046. Personally, I would avoid the NTE version. Texas Instruments still makes this somewhat obsolete CD4046 IC. These will probably be discontinued soon like many of the older logic series IC's.
Meyer could not have used an NTE4046 since NTE did not make a 4046 in 1985. Meyer probably used a National Semiconductor or ST Micro version of the 4046.
Stevie, you may want to double check your stated "400ma" output specification. These are low power devices designed to clock CMOS logic. 2- 4 ma would be about max. At 12 Volts out and 400ma that would be about 2.4 watts at 50 % duty cycle. Not likely to happen without some smoke since this chip can only dissipate 500mw max.
Another interesting IC is the older 74LS629. This is a dual VCO Chip ( NO PLL) good to about 20 mhz.