The following couple of circuit diagrams provide a glimpse of the configuration for making a precision rectifier and direct coupled power source circuits.
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| Precission Rectifier circuit diagram. |
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| Direct Coupled Power Circuit Diagram |
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| CMOS Power Booster Circuit Diagram |
The MC1556 operational amplifier way be used as a voltage follower ln a
hid; amplifier application. The high input impedance avoids loading
effects on the bridge and transforms the impedance down to a level where
a third amplifier used in a differential mode can provide voltage gain,
ll) in this case. The third amplifier employs the standard offset
adjust circuit to provide nulling capability for the configuration.
Although the circuit is shown for complementary supply voltages, , it
lends itself well to operation from a single supply since the bridge can
be operated iust as well from the single supply. One must,
however,,provide for biasing the nowgrounded 100 kS2 resistor to half
the supply voltage using a simple resistive divider. Also.- of course,
the output is no longer referenced to ground, but to half the supply
voltage. In the circuit the output from an LM3900 N amplifier is fed to a
Darlington pair of power transistqrs. can deliver over three a suitable
load when the are correctly mounted on The current·sourcing and sinking
capability of the CA513O output stage is easily supplemented to pro-
vide powenboost capability. ln the ' circuit three COS/MOS transistor-
pairs in a single CA36OOE IC array are shown parallel connected with the
output stage in the CA5l30. Jn the Class A mode of CA36OOE shown, a
typical device consumes 20 mA of supply current at 1 5V operation. This
arrangement boosts the current- handling capability of the CA3l3O output
stage by about 2.5.courtesy - ETI Electronics