L6713A STMicroelectronics, L6713A Datasheet - Page 36

• Manufacturer Part Number: L6713A
• Description: IC CTRLR 2/3PH W/DRIVERS 64-TQFP
• Manufacturer: STMicroelectronics

Specifications of L6713A

• Applications: Controller, Intel VR10, VR11, AMD CPU
• Voltage - Input: 12V
• Number Of Outputs: 3
• Voltage - Output: 0.3 ~ 1.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 64-TQFP Exposed Pad, 64-eTQFP, 64-HTQFP, 64-VQFP
• Output Current: 2 A
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Voltage positioning
12.2
36/64
Droop function (Optional)
This method "recovers" part of the drop due to the output capacitor ESR in the load
transient, introducing a dependence of the output voltage on the load current: a static error
proportional to the output current causes the output voltage to vary according to the sensed
current.
As shown in
the total deviation of the output voltage is minimized. Moreover, more and more high-
performance CPUs require precise load-line regulation to perform in the proper way.
DROOP function is not then required only to optimize the output filter, but also beacomes a
requirement of the load.
Connecting DROOP pin and FB pin together, the device forces a current I
proportional to the read current, into the feedback resistor (R
load regulation dependence. Since I
phases, the output characteristic vs. load current is then given by (neglecting the OFFSET
voltage term):
Where DCR is the inductor parasite resistance (or sense resistor when used) and I
output current of the system. The whole power supply can be then represented by a "real"
voltage generator with an equivalent output resistance R
R
Droop function is optional, in case it is not desired, the DROOP pin can be disconnected
from the FB and an information about the total delivered current becomes available for
debugging, and/or current monitoring. When not used, the pin can be shorted to SGND.
FB
resistor can be also designed according to the R
Figure
V
REF
11, the ESR drop is present in any case, but using the droop function
–
(
R
FB
V
+
OUT
R
R
FB
OFFSET
=
=
V
DROOP
R
REF
DROOP
)
⋅
DCR
------------ - I
–
Rg
(
depends on the current information about the N
R
FB
⋅
⋅
------------ - R
DCR
Rg
+
OUT
R
OFFSET
–
=
DROOP
V
OFFSET
REF
DROOP
) I
⋅
–
specifications as follow:
FB
DROOP
R
+R
DROOP
and a voltage value of V
OFFSET
⋅
I
OUT
) implementing the
DROOP
,
OUT
L6713A
is the
REF
.