L6711TR STMicroelectronics, L6711TR Datasheet - Page 37

• Manufacturer Part Number: L6711TR
• Description: IC CTRLR 3PHASE VID/DACS 48-TQFP
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L6711TR

• Internal Switch(s): No
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 0.8 ~ 1.55 V
• Current - Output: 2A
• Frequency - Switching: 150kHz
• Voltage - Input: 12V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 48-TQFP Exposed Pad, 48-eTQFP, 48-HTQFP, 48-VQFP
• Power - Output: 2.5W
• Output Voltage: 0.8 V to 1.581 V
• Output Current: 95 A
• Input Voltage: 13.8 V
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-5363-2; L6711TR

L6711
14.6
Figure 18. Constant current operation
Inductor sense over current (CS_SEL = SGND)
The device detects an over current when the I
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 LS mosfet of that phase until I
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, the FAULT pin is driven high 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.
Rg
=
I
-------------------------------------------------------------------- -
OCPx max
T o n M
I
a) Maximum current for each phase
OC TH min
A X
R
SENSE max
T o n M
where
A X
I
OCPx
=
INFOx
I
-------------------------- -
OUT OCP
Output voltage monitor and protections
3
overcome the fixed threshold I
I p e a k
I
I
M
O C P x
A X
OCPx
+
----------- -
value and this will represent the
I
2
b) Output Characteristic
PP
V o u t
U V P
+
I
--------------
D-VID
3
OCTH
D r o o p e f f e c t
INFOx
3 · I
crossing will
O C P x
( I
D R O O P
re-cross the
I
M
A X , T O
= 1 0 5A )
OCTH
T
I o u t
37/50
.