CES CEM3394, Quick Start Manual

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Page 3
CEM3394 Electrical Specifications (cont)
PARAMETER MIN TYPICAL MAX UNITS
FINAL VCA
Attenuation at CV = 0
80 90 --- dB
CV for Maximum Output 3.8 4.0 4.3 V
CV Scale Factor (20-100dB) --- 20 --- dB/V
Triangle Wave Output Level 190 250 325 uA pp
Tr Sawtooth Output 255 330 430 uA pp
Sawtooth Output Level 150 200 260 uA pp
Square Wave Output Level 120 160 210 uA pp
All Waves On Output Level 300 400 520 uA pp
CV Feedthrough --- +-0.3 +-3.0 uA
CV Input Current --- 0.3 3.0 nA
POWER SUPPLIES
Positive Supply Range +4.75 --- +8.0 V
Negative Supply Range -4.75 --- -16.0 V
Positive Supply Current 13 16 21 mA
Negative Supply Current -13 -16 -21 mA
APPLICATION HINTS
POWER SUPPLY
The CEM3394 was designed to operate from +5V and -6.5V supplies. The non-standard negative
supply was necessary not to compromise the VCO frequency resolution, which ranges from -4 to +4
volts, in favor of a -5V supply (this is because there needs to be 4 diode drops for the current
mirrors…ed). Any one of the readily available 3-terminal regulators (LM337, for example) may be
used to supply the -6.5V negative supply. Since the stability and jitter of the VCO are directly
affected by noise on the positive supply, a supply as stable and clean as possible should be use (not
the +5V digital supply…ed.) Maximum supply allowable across the device is 25 volts.
VCO
The control scale of the VCO is temperature compensated with an in3300ppm tempco
generator and multiplier. Thus, as chip temperature changes, the control voltage applied to the
exponential generator changes proportional to temperature, effectively canceling the -3300ppm
tempco of the control scale.