L6740L datasheet(9/44 Pages) STMICROELECTRONICS

9 / 44 page

L6740L

Pins description and connection diagrams

9/44

FBG

Remote ground sense.

Connect to the negative side of the load for remote sensing. See

Section 9 for proper layout of this connection.

8OS

Offset programming pin.

Internally set to 1.24V. Connecting a ROS resistor to SGND allows to set

a current that is mirrored into FB pin in order to program a positive off-

set according to the selected RFB.

Short to SGND to disable the function. See Section 6.4 for details.

9LTB

LTB TechnologyTM Input pin.

Connect through an RLTB - CLTB network to the regulated voltage

(CORE Section) to detect load transient. See Section 10 for details.

OVP / V_FIX

OVP. Over Voltage Programming Pin. Internally pulled-up to 3.3V by

µA. Connect to SGND through a R

OVP resistor and filter with 10nF

(typ) to set a fixed voltage according to the ROVP resistor. If floating it

will program 3.3V threshold. See Section 7 for details.

V_FIX - Hardware override. Short to SGND to enter VFIX mode

(WARNING: this condition overrides any code programmed on the VIDx

lines). In this case, the device will use SVI inputs as static VIDs and

OVP threshold will be set to 1.8V. See Section 5.4.5 for details.

LTB_GAIN

LTB TechnologyTM gain pin.

Connect to SGND through a resistor RLTBGAIN to program the LTB

Gain. See Section 10 for details.

PSI_L

Power Saving Indicator (SVI Mode).

Open-drain Input/Output pin. See Section 5.4.3 for details.

CS1+

Channel 1 Current Sense Positive Input. Connect through an R-C filter

to the phase-side of the channel 1 inductor.