AE Techron 7800 Series Operation Manual page 32

STEP 3: Determine if Default or Custom Compensation is Required.
If your load inductance is between 200 microHen-
ries and 1 milliHenry, and your load resistance
is less than 5 ohms, then you can likely use the
default compensation provided by the amplifier's
factory-installed RC network. To select the factory-
default compensation, please see STEP 4 below.
STEP 4: (Optional) Verify Suitability of Default Compensation (CC1)
If desired, the following values of the components
contained in the default RC network can be used
with the formulas provided in STEP 5 below to
verify the suitability of the default compensation for
your uses.
STEP 5: Calculating Values for an RC Network for Custom Compensation
\If the default RC network does not provide suit-
able compensation for your intended load, you
will need to install a custom RC network that is
matched to your load. This network will require two
components (a resistor (R) and a capacitor (C))
to be installed on the main board. To calculate the
approximate values required for each component,
use the following formulas.
COMPENSATION FORMULAS:
To find the value for the resistor (Rc) in the RC
network:
Rc = 20,000 x 3.14 x L x BW where:
STEP 6: Installing and Enabling the Custom RC Network
Once an approximate Rc and Cc have been com-
puted, these values will need to be evaluated. To
do this, you will need to install the custom compo-
nents on the amplifier's main board and enable the
alternate compenation network (CC2).
32
If your load inductance falls outside of the mid-
range, or if your load resistance is greater than
5 ohms, then you must calculate your required
compensation. If, after calculating your required
compensation, you determine that the default com-
pensation will be insufficient for your load, then
you will need to enable and install a custom RC
network. See STEP 6 below.
Compensation Resistor: 68.1k ohms
Compensation Capacitor: 47 nF
Parallel Capacitor: 100 pF
Rc is compensation resistance in ohms.
L is load inductance in henries.
BW is bandwidth in hertz.
To find the value for the capacitor (Cc) in the
RC network:
Cc = L/ (R x Rc)
where:
Cc is compensation capacitance in farads.
L is load inductance in henries.
R is resistance of load in ohms.
Rc is compensation resistance in ohms.
The main board can be accessed by removing the
amplifier top cover. To remove the amplifier top
cover, complete the steps detailed in the following
section.
Information subject to change
7800 SERIES OPERATION – SECTION 5
96-8007105_07-14-23