LTC3607
pin FuncTions (QFN/MSE)
PV , PV , SV (Pins6, 7, 3/Pins4, 5, 1):Main Power
PGOOD1 (Pin 2/Pin 16): Regulator 1 Power Good. This
common-drain logic output is pulled to SGND when the
channel1outputvoltageisnotwithin 8.5%ofregulation.
IN1
IN2
IN
Supply. Must be closely decoupled to GND. These inputs
may each be powered from different supply voltages.
Connect SV to either PV or PV , whichever one
IN
IN1
IN2
V
(Pin 14/Pin 12): Regulator 2 Output Feedback.
FB2
is higher. For applications where it’s not known which
Receives the feedback voltage from the external resistor
divider across the regulator 2 output. Nominal voltage for
this pin is 0.6V.
PV ishigher,connectexternaldiodesbetweenSV
IN(1or2)
IN
to both PV and PV to ensure that SV is less than a
IN1
IN2
IN
IN2
diode drop from the higher of PV or PV
.
IN1
SW2 (Pin 8/Pin 6): Regulator 2 Switch Node Connection
PGND1,PGND2,SGND,PGND(Pins4,9,10,12,Exposed
to the Inductor. This pin switches from PV to PGND2.
IN2
Pad Pin 17/Pins 2, 7, 8, 10, Exposed Pad Pin 17): Main
RUN2 (Pin 13/Pin 11): Regulator 2 Enable. Forcing this
pin high (above 3.0V) enables regulator 2, while forcing
it to SGND causes regulator 2 to shut down. It is possible
Ground. Connect to the (–) terminals of C
, C
, and
OUT1 OUT2
C . The exposed pad must be soldered to PCB ground for
IN
electricalcontactandratedthermalperformance.AllSGND
to use a 3.3V source to drive this pin, or tie it to SV .
and PGND pins must be externally connected to ground.
IN
An internal soft-start limits the rise time to a minimum
V
(Pin 15/Pin 13): Regulator 1 Output Feedback.
FB1
of 0.35ms.
Receives the feedback voltage from the external resistor
divider across the regulator 1 output. Nominal voltage for
this pin is 0.6V.
PGOOD2 (Pin 11/Pin 9): Regulator 2 Power Good. This
common-drain logic output is pulled to SGND when the
channel2outputvoltageisnotwithin 8.5%ofregulation.
SW1 (Pin 5/Pin 3): Regulator 1 Switch Node Connection
to the Inductor. This pin switches from PV to PGND1.
MODE/SYNC (Pin 1/Pin 15): Combination Mode Selec-
tion and Oscillator Synchronization. This pin controls the
light-load behavior of the device. Forcing this pin to SGND
selects pulse-skipping mode. Floating this pin or forcing
it above 1V selects Burst Mode operation. The internal
oscillation frequency can be synchronized to an external
oscillator applied to this pin and pulse-skipping mode is
automatically selected.
IN1
RUN1 (Pin 16/Pin 14): Regulator 1 Enable. Forcing this
pin high (above 3V) enables regulator 1, while forcing it
to SGND causes regulator 1 to shut down. It is possible
to use a 3.3V source to drive this pin, or tie it to SV .
IN
An internal soft-start limits the rise time to a minimum
of 0.35ms.
3607fb
6
For more information www.linear.com/LTC3607
Linear Systems [ Linear Systems ]
