MAX16974EVKIT+ Maxim Integrated Products, MAX16974EVKIT+ Datasheet - Page 17

• Manufacturer Part Number: MAX16974EVKIT+
• Description: Power Management Modules & Development Tools MAX16974 EVAL KIT MAX16974 EVAL KIT
• Manufacturer: Maxim Integrated Products

Specifications of MAX16974EVKIT+

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The total loop gain as the product of the modulator gain,
the feedback voltage-divider gain, and the error amplifier
gain at f
For the case where f
Therefore:
Solving for R
Set the error-amplifier compensation zero formed by R
and C
as follows:
If f
C
formed by R
value of C
As the load current decreases, the modulator pole also
decreases; however, the modulator gain increases
accordingly and the crossover frequency remains the
same.
For the case where f
The power-modulator gain at f
F
, from COMP to GND and set the compensation pole
zMOD
C
Down Converter with Low Operating Current
C
GAIN
GAIN
(f
GAIN
GAIN
is less than 5 x f
zEA
F
should be equal to 1. So:
High-Voltage, 2.2MHz, 2A Automotive Step-
R
as follows:
C
C
C
) at the f
MOD(fC)
MOD(fC)
:
MOD(fC)
MOD(fC)
and C
=
GAIN
C
g
C
______________________________________________________________________________________
m,EA
C
F
F
=
=
EA(fC)
zMOD
zMOD
pMOD
(f
=
2
2
=
×
×
×
pEA
π ×
π ×
GAIN
GAIN
V
V
V
V
V
OUT
OUT
FB
FB
FB
f
f
C
) at the f
=
pMOD
zMOD
V
is greater than f
is less than f
. Calculate the value of C
, add a second capacitor,
OUT
g
×
MOD(DC)
MOD(DC)
1
C
1
m,EA
×
GAIN
×
is:
GAIN
g
×
m,EA
×
R
R
×
zMOD
MOD(fC)
C
R
C
EA(fC)
C
×
×
×
R
f
f
f
pMOD
pMOD
zMOD
. Calculate the
C
C
f
:
C
=
=
C
1
1
:
C
C
The error-amplifier gain at f
Therefore:
Solving for R
Set the error-amplifier compensation zero formed by R
and C
If f
from COMP to GND. Set f
as follows:
Careful PCB layout is critical to achieve low switching
losses and clean, stable operation. Use a multilayer
board whenever possible for better noise immunity and
power dissipation. Follow these guidelines for good PCB
layout:
1) Use a large contiguous copper plane under the IC
2) Isolate the power components and high-current path
3) Keep the high-current paths short, especially at the
zMOD
package. Ensure that all heat-dissipating compo-
nents have adequate cooling. The bottom pad of the
device must be soldered down to this copper plane
for effective heat dissipation and getting the full
power out of the IC. Use multiple vias or a single large
via in this plane for heat dissipation.
from the sensitive analog circuitry. This is essential to
prevent any noise coupling into the analog signals.
ground terminals. This practice is essential for stable,
jitter-free operation. The high-current path composed
of input capacitor, high-side FET, inductor, and the
output capacitor should be as short as possible.
GAIN
C
R
at the f
is less than 5 O f
C
MOD(fC)
=
GAIN
C
g
:
m,EA
pMOD
EA(fC)
C
C
×
F
C
×
V
=
V
=
V
(f
OUT
FB
2
FB
=
zEA
2
π ×
π ×
g
×
C
pEA
V
m,EA
, add a second capacitor, C
×
GAIN
f
PCB Layout Guidelines
C
OUT
= f
f
zMOD
pMOD
g
is:
m,EA
pMOD
1
= f
1
×
×
MOD(fC)
R
zMOD
f
×
C
C
×
×
R
):
R
R
×
C
C
C
f
zMOD
and calculate C
×
f
×
C
f
zMOD
f
zMOD
f
C
=
1
17
F
C
F
,