ADP3203JRU-10-RL7 AD [Analog Devices], ADP3203JRU-10-RL7 Datasheet - Page 11

• Manufacturer Part Number: ADP3203JRU-10-RL7
• Description: 2-Phase IMVP-II & IMVP-III Core Controller for Mobile CPUs
• Manufacturer: AD [Analog Devices]

REV. PrD
6. An external "antiparallel" schottky diode (across the
7. The VCC bypass capacitor should be close to the VCC
Output Filter
Output Inductor and Capacitors, Current Sense Resistor
8. Locate the current sense resistors very near to the output
9. The load-side heads of two sense resistors should join as
10. PCB trace resistances from the current sense resistors to
11. Whenever high currents must be routed between PCB
Control Circuitry
ADP3203, Control Components
12. If the ADP3203 cannot be placed as previously recom-
13. Noise immunity can be improved by the use of a
14. If critical signal lines (i.e., signals from the current sense
near the MOSFETs will help. Even just small airflow
can help tremendously. Paralleled MOSFETs to achieve
a given resistance will help spread the heat.
bottom MOSFET) may help efficiency a small amount
(< ~1 %) depending on its forward voltage drop com-
pared to the MOSFET's body diode at a given current; a
MOSFET with a built in antiparallel schottky is more
effective. For an external schottky, it should be placed
next to the bottom MOSFET or it may not be effective
at all.
pin and connected on either a very short trace to the
GND pin or to the GND plane.
voltage plane.
closely as possible for accurate current signal measure-
ment of each phase.
the regulation point should be minimized, known
(calculated or measured), and compensated for as part
of the design if it is significant. (Remote sensing is not
sufficient for relieving this requirement!) A square
section of 1-ounce copper trace has a resistance of
~500 m
resistance of the power converter. The output capaci-
tors should similarly be close to the regulation point and
well tied into power planes as impedance here will add
to the "AC output resistance" (i.e., the ESR) that is
implicitly specified as well.
layers, vias should be used liberally to create parallel
current paths so that the resistance and inductance is
minimized and the via current rating is not exceeded.
mended, at the least care should be taken to keep the
device and surrounding components away from radia-
tion sources (e.g., from power inductors) and capacitive
coupling from noisy power nodes.
devoted signal ground plane for the power controller
and its surrounding components. Space for a ground
plane might readily be available on a signal plane of the
PCB since it is often unused in the vicinity of the power
controller.
resistor leading back to the ADP3203) must cross
through power circuitry, it is best if a signal ground
plane can be interposed between those signal lines and
the traces of the power circuitry. This serves as a shield
to minimize noise injection into the signals.
and this adds to the specified DC output
PRELIMINARY TECHNICAL DATA
–11–
15. Absolutely avoid crossing any signal lines over the
16. Accurate voltage positioning depends on accurate
17. The RC filter used for the current sense signal should be
VID4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
switching power path loop, described previously.
current sensing, so the control signals which monitor the
voltage differentially across the current sense resistor
should be kelvin connected. Please refer to ADI Evalua-
tion Board of the ADP3203 and its documentation for
control signal connection with sense resistors.
located near the control components as this serves the
dual purpose of filtering out the effect of the current
sense resistors' parasitic inductance and noise picked up
along the routing of the signal. The former purpose is
achieved by having the time constant of the RC filters
approximately matched to that of the sense resistors and
is important for maintaining the accuracy of the current
signal.
VID3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
VID2
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
TABLE 1. VID CODE
VID1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
VID0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
ADP3203
VOUT
1.750
1.700
1.650
1.600
1.550
1.500
1.450
1.400
1.350
1.300
1.250
1.200
1.150
1.100
1.050
1.00
0.975
0.950
0.925
0.900
0.875
0.850
0.825
0.800
0.775
0.750
0.725
0.700
0.675
0.650
0.625
0.600