
Obsolete
Product(s)
- Obsolete
Product(s)
L6711
Pins description and connection diagrams
9/50
17
CS2+
Channel 2 Current Sense Positive Input pin.
It must be connected through an Rg resistor to the LS mosfet source (or to the GND-side of
the sense resistor placed in series to the LS mosfet) if LS mosfet sense is performed
(CS_SEL=OPEN). Otherwise (CS_SEL=SGND), it must be connected to the phase-side of
the output inductor (or the inductor-side of the sense resistor used and placed between the
channel 2 inductor and the output of the converter) through Rg resistor and an R-C network
across the inductor.
The net connecting the pin to the sense point must be routed as close as possible to the CS2-
net in order to couple in common mode any picked-up noise.
18
CS3-
Channel 3 Current Sense Negative Input pin.
It must be connected through an Rg resistor to the LS mosfet drain (or to the LS-side of the
sense resistor placed in series to the LS mosfet) if LS mosfet sense is performed
(CS_SEL=OPEN). Otherwise (CS_SEL=SGND), it must be connected to the output-side of
the output inductor (or the output-side of the sense resistor used and placed between the
channel 3 inductor and the output of the converter) through Rg resistor.
The net connecting the pin to the sense point must be routed as close as possible to the CS3+
net in order to couple in common mode any picked-up noise.
19
CS3+
Channel 3 Current Sense Positive Input pin.
It must be connected through an Rg resistor to the LS mosfet source (or to the GND-side of
the sense resistor placed in series to the LS mosfet) if LS mosfet sense is performed
(CS_SEL=OPEN). Otherwise (CS_SEL=SGND), it must be connected to the phase-side of
the output inductor (or the inductor-side of the sense resistor used and placed between the
channel 3 inductor and the output of the converter) through Rg resistor and an R-C network
across the inductor.
The net connecting the pin to the sense point must be routed as close as possible to the CS3-
net in order to couple in common mode any picked-up noise.
20
TC
Temperature Compensation pin.
Connect through a resistor RTC and filter with 10nF vs. SGND to program the temperature
compensation effect.
Short to SGND to disable the compensation effect.
21
CS_SEL
Current Reading Selection pin, internally 5V pulled-up.
Leave floating to sense current across low-side mosfets or a sense resistor placed in series to
the LS mosfet source. Maximum duty cycle is dynamically limited and Track&Hold is enabled
to assure proper reading of the current.
Short to SGND to read current across inductors or a sense resistor placed in series to the
output inductors. No duty cycle limitation and no Track&Hold performed in this case.
22
OSC /
FAULT
Oscillator pin.
It allows programming the switching frequency of each channel: the equivalent switching
frequency at the load side results in being tripled.
Internally fixed at 1.24V, the frequency is varied proportionally to the current sunk (forced)
from (into) the pin with an internal gain of 6kHz/
A (See relevant section for details).
If the pin is not connected, the switching frequency is 150kHz for each channel (450kHz on the
load).
The pin is forced high (5V Typ.) when an Over/Under Voltage is detected; to recover from this
condition, cycle VCC or the OUTEN pin.
Table 1.
Pins description (continued)
N°
Name
Description