L6714 STMicroelectronics, L6714 Datasheet - Page 53

• Manufacturer Part Number: L6714
• Description: IC CTRLR 4PH W/DRIVERS 64-TQFP
• Manufacturer: STMicroelectronics

Specifications of L6714

• Applications: Controller, Intel VR10, VR11, AMD CPU
• Voltage - Input: 12V
• Number Of Outputs: 4
• 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
• Mounting Style: SMD/SMT
• Case: QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

L6714
18.2
Inductor sense over current
The device detects an over current when the II
Since the device always senses the current across the inductor, the I
happen during the HS conduction time: as a consequence of OCP detection, the device will
turn OFF the HS MOSFET and turns ON the LSMOSFET of that phase until I
the threshold or until the next clock cycle. This implies that the device limits the peak of the
inductor current.
In any case, the inductor current won't overcome the I
maximum peak value to consider in the OC design.
The device works in Constant-Current, and the output voltage decreases as the load
increase, until the output voltage reaches the UVP threshold. When this threshold is
crossed, all MOSFETs are turned off and the device stops working. Cycle the power supply
or the OUTEN pin to restart operation.
The transconductance resistor Rg can be designed considering that the device limits the
inductor current ripple peak. Moreover, when designing D-VID systems, the additional
current due to the output filter charge during dynamic VID transitions must be considered.
where
I
OCPx
Rg
=
=
I
-----------------------------------------------------------------------
OCPx max
I
-------------------------- -
OUT OCP
N
I
OCTH min
NFOx
+
R
----------- -
SENSE max
I
2
PP
overcome the fixed threshold I
OCPx
+
I
----------------- -
D VID
–
N
value and this will represent the
Over current protection
OCTH
crossing will
INFOx
OCTH
re-cross
53/70
.