ADP3211AMNR2G ON Semiconductor, ADP3211AMNR2G Datasheet - Page 28

• Manufacturer Part Number: ADP3211AMNR2G
• Description: IC CTLR BUCK 7BIT 2PHASE 32QFN
• Manufacturer: ON Semiconductor

Specifications of ADP3211AMNR2G

• Applications: Controller, Power Supplies for Next-Generation Intel Processors
• Voltage - Input: 3.3 ~ 22 V
• Number Of Outputs: 1
• Voltage - Output: 0.0125 ~ 1.5 V
• Operating Temperature: -10°C ~ 100°C
• Mounting Type: Surface Mount
• Package / Case: 32-TFQFN Exposed Pad
• Output Voltage: 1.1 V
• Output Current: 10 A
• Input Voltage: 19 V
• Supply Current: 6 mA
• Switching Frequency: 400 KHz
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 100 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

for the poles and zeros in the system and are intended to
yield an optimal starting point for the design; some
adjustments may be necessary to account for PCB and
component parasitic effects (see the Tuning Procedure for
ADP3211 section):
where:
R’ is the PCB resistance from the bulk capacitors to the
ceramics and is approximately 0.4 mW (assuming an
8−layer motherboard).
R
A
V
L
Panasonic SP capacitors).
the tuning procedure described in the Tuning Procedure for
ADP3211 section.
C
of the high−side MOSFET is approximately a square wave
with a duty ratio equal to V
voltage transients, use a low ESR input capacitor sized for
the maximum RMS current.
T
T
R
T
X
IN
T
DS
D
RT
The expressions that follow compute the time constants
The compensation values can be calculated as follows:
The standard values for these components are subject to
In continuous inductor−current mode, the source current
A
B
E
C
D
is the ESL of the bulk capacitors (450 pH for the two
is 5.
+ C
+ (R
Selection and Input Current D
+ R
is the total low−side MOSFET for on resistance.
is 1.25 V.
+
+
2
V
C
R
C
C
C
X
O
X
RT
A
A
FB
B
X
C
) A
) R * R
+
+
+
L
X
+
(R
V
C
(R
R
C
R
T
T
R
R
D
VID
O
X
C
D
E
A
T
A
(1 * D)
L *
O
O
R
FB
* R ) )
B
O
* R ) ) C
R
C
R
A
O
T
DS
R
2 f
Z
FB
D
)
A
V
E
)
VID
R
SW
R
R
C
DS
L
V
R
O
X
O
X
RT
DCR
Z
2
OUT
V
VID
R
R
O
/V
O
R
I
V
/D
* R
IN
X
RT
T
. To prevent large
Reduction
)
(eq. 35)
(eq. 36)
(eq. 37)
(eq. 38)
(eq. 39)
(eq. 40)
(eq. 41)
(eq. 42)
(eq. 43)
http://onsemi.com
28
The maximum RMS capacitor current occurs at the lowest
input voltage and is given by:
where I
is achieved by using MLC capacitors or a mixture of MLC
capacitors and bulk capacitors. In this example, the input
capacitor bank is formed by four pieces of 10 mF, 25 V MLC
capacitors, with a ripple current rating of about 1.5 A each.
Tuning Procedure for ADP3211
Set Up and Test the Circuit
Set the DC Load Line
In a typical notebook system, the battery rail decoupling
1. Build a circuit based on the compensation values
2. Connect a dc load to the circuit.
3. Turn on the ADP3211 and verify that it operates
4. Check for jitter with no load and full load
1. Measure the output voltage with no load (V
2. Measure the output voltage with a full load when
3. Repeat Step 2 until no adjustment of R
4. Compare the output voltage with no load to that
5. If the difference between R
6. Repeat Steps 4 and 5 until no adjustment of R
R
computed from the design spreadsheet.
properly.
conditions.
and verify that this voltage is within the specified
tolerance range.
the device is cold (V
run for ~10 minutes with a full load and then
measure the output when the device is hot
(V
measured voltages is more than a few millivolts,
adjust R
needed.
with a full load using 5 A steps. Compute the
load line slope for each change and then find the
average to determine the overall load line slope
(R
than 0.05 mW, use the following equation to
adjust the R
is needed. Once this is achieved, do not change
R
procedure.
O
I
I
CS2(NEW)
CRMS
CRMS
R
PH
is the output current.
FLHOT
OMEAS
PH(NEW)
, R
+ D
+ 0.15
CS1
CS2
). If the difference between the two
).
+ R
, R
+ R
PH
using Equation 45.
CS2
CS2(OLD)
I
O
values:
PH(OLD)
15 A
, or R
FLCOLD
D
1
TH
* 1
V
R
for the rest of the
V
0.15
NL
OMEAS
NL
OMEAS
R
1
). Allow the board to
* V
O
* V
* 1 + 5.36 A
FLCOLD
FLHOT
and R
CS2
O
(eq. 44)
(eq. 45)
(eq. 46)
is more
is
NL
PH
)