Datasheet

L6730 - L6730B Pin connections and functions
Doc ID 11938 Rev 3 9/52
4
T
MASK
The user can select two different values for the leading edge blanking
time on the peak overcurrent protection by connecting this pin to V
CCDR or
GND. The device captures the analog value present at this pin at the
start-up when VCC meets the UVLO threshold.
5GND
All the internal references are referenced to this pin. Connect to the PCB
signal ground.
6FB
This pin is connected to the error amplifier inverting input. Connect it to
Vout through the compensation network. This pin is also used to sense
the output voltage in order to manage the over voltage conditions and the
PGood signal.
7COMP
This pin is connected to the error amplifier output and used to
compensate the voltage control loop.
8 SS/INH
The soft-start time is programmed connecting an external capacitor from
this pin and GND. The internal current generator forces a current of 10mA
through the capacitor. This pin is also used to inhibit the device: when the
voltage at this pin is lower than 0.5V the device is disabled.
9 EAREF
It is possible to set two internal references 0.6V / 1.2V or provide an
external reference from 0V to 2.5V:
V
EAREF
from 0% to 80% of V
CCDR
-> external reference
V
EAREF
from 80% to 95% of V
CCDR
-> V
REF
=1.2V
V
EAREF
from 95% to 100% of V
CCDR
-> V
REF
=0.6V
An internal clamp limits the maximum V
EAREF
at 2.5V (typ.). The device
captures the analog value present at this pin at the start-up when V
CC
meets the UVLO threshold.
10 OSC
Connecting an external resistor from this pin to GND, the external
frequency can be increased according with the following equation:
Connecting a resistor from this pin to V
CCDR
(5V), the switching frequency
can be lowered according with the following equation:
If the pin is left open, the switching frequency is 400 KHz. Normally this
pin is at a voltage of 1.2V. In OVP the pin is pulled up to 4.5V (only in
latched mode). Don’t connect a capacitor from this pin to GND.
Table 4. Pin connection (continued)
Pin n. Name Description
)(
1088.9
400
6
Ω
⋅
+=
KR
KHzFsw
OSC
)(
1001.3
400
7
Ω
⋅
−=
KR
KHzFsw
OSC