LTC3428 Datasheet, PDF (4/12 Pages) Linear Technology – 4A, 2MHz Dual Phase Step-Up DC/DC Converter in 3mm 3mm DFN

LTC3428
TYPICAL PERFOR A CE CHARACTERISTICS
Peak Current Limit vs
Temperature
3.4
3.2
3.0
2.8
2.6
2.4
2.2
2.0
–45 –25 –5 15 35 55
TEMPERATURE (°C)
75 95
3428 G10
PI FU CTIO S
PGNDA, PGNDB (Pins 1, 10, 11 (Exposed Pad)): Power
Ground for the IC. Tie directly to local ground plane.
SWB (Pin 2), SWA (Pin 9): Phase B and Phase A Switch
Pins. The inductor and Schottky diodes for each phase are
connected to these pins. Minimize trace length to reduce
EMI.
V_OUT (Pin 3): Power Supply Output and Bootstrapped
Power Source for the IC. Connect low ESR output filter
capacitors from this pin to the ground plane.
SHDN (Pin 4): Shutdown Pin. Grounding this pin shuts
down the IC. Connect to a voltage greater than 1.5V to
enable.
V_C (Pin 5): Error Amp Output. A frequency compensation
network is connected to this pin to compensate the boost
converter loop.
FB (Pin 6): Feedback Pin. A resistor divider from V_OUT is
connected here to set the output voltage according to
V_OUT = 1.243 • (1 + R1 / R2)
AGND (Pin 7): Signal Ground for the IC. Connect to ground
plane near feedback resistor divider.
V_IN (Pin 8): Input Supply Pin. Bypass V_IN with a low ESR
ceramic capacitor of at least 4.7µF. X5R and X7R dielec-
trics are preferred for their superior voltage and tempera-
ture characteristics.
3428f
4