LT3980EDE#TRPBF Linear Technology, LT3980EDE#TRPBF Datasheet - Page 7

• Manufacturer Part Number: LT3980EDE#TRPBF
• Description: IC SWITCHING REG STP-DN 2A 14DFN
• Manufacturer: Linear Technology
• Type: Step-Down (Buck)r

Specifications of LT3980EDE#TRPBF

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 0.79 ~ 52.2 V
• Current - Output: 2A
• Frequency - Switching: 100kHz ~ 2.4MHz
• Voltage - Input: 3.6 ~ 58 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 14-DFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -

BLOCK DIAGRAM
SYNC (Pin 1/Pin 1): This is the external clock synchro-
nization input. Ground this pin for low ripple Burst Mode
operation at low output loads. Tie to a clock source for
synchronization. Clock edges should have rise and fall
times faster than 1μs. Tie pin to GND if not used. See the
Synchronization section in Applications Information.
NC (Pins 2, 13/Pins 3, 5, 13, 16): No Connect. These
pins are not connected to internal circuitry.
PG (Pin 3/Pin 2): The PG pin is the open collector output
of an internal comparator. PG remains low until the FB pin
is within 9% of the fi nal regulation voltage. PG output is
valid when V
FB (Pin 4/Pin 4): The LT3980 regulates the FB pin to 0.790V.
Connect the feedback resistor divider tap to this pin.
V
error amplifi er. The voltage on this pin controls the peak
switch current. Tie an RC network from this pin to ground
to compensate the control loop.
RT (Pin 6/Pin 7): Oscillator Resistor Input. Connecting
a resistor to ground from this pin sets the switching
frequency.
GND (Pin 7, 15/Pin 8, 17): Ground. The exposed pads
must be soldered to the PCB.
PIN FUNCTIONS
C
(Pin 5/Pin 6): The V
V
IN
IN
R
C1
T
is above 3.6V and RUN/SS is high.
V
RUN/SS
RT
PG
SYNC
IN
SOFT-START
C
pin is the output of the internal
GND
(DFN, MSOP)
INTERNAL 0.79V REF
+
–
R2
0.725V
FB
R1
ERROR AMP
+
–
100kHzTO2.4MHz
SLOPE COMP
OSCILLATOR
–
+
RUN/SS (Pin 8/Pin 9): The RUN/SS pin is used to put the
LT3980 in shutdown mode. Tie to ground to shut down
the LT3980. Tie to 2.5V or more for normal operation. If
the shutdown feature is not used, tie this pin to the V
pin. RUN/SS also provides a soft-start function; see the
Applications Information section.
BD (Pin 9/Pin 10): This pin connects to the anode of the
boost Schottky diode. BD also supplies current to the
internal regulator.
BOOST (Pin 10/Pin 11): This pin is used to provide a drive
voltage, higher than the input voltage, to the internal bipolar
NPN power switch.
SW (Pin 11/Pin 12): The SW pin is the output of the
internal power switch. Connect this pin to the inductor,
catch diode and boost capacitor.
V
LT3980’s internal regulator and to the internal power switch.
This pin must be locally bypassed.
DA (Pin 14/Pin 15): This pin measures catch diode current
and pauses the oscillator during overcurrent conditions.
IN
(Pin 12/Pin 14): The V
BurstMode
V
R
S
SWITCH
DETECT
C
LATCH
CLAMP
DISABLE
Q
BOOST
SW
BD
DA
V
C
IN
pin supplies current to the
R
C
C
D1
C
C3
L1
C
F
C2
3680 BD
LT3980
V
OUT
7
3980f
IN