MP1495S – SYNCHRONOUS STEP-DOWN CONVERTER
PIN FUNCTIONS
Package
Pin #
Name Description
Advanced Asynchronous Modulation. Connect the tap of 2 resistor dividers to force the
MP1495S into non-synchronous mode under light loads. Drive AAM pin high (VCC) to
force the MP1495S into CCM.
1
AAM
Supply Voltage. The MP1495S operates from a 4.5V to 16V input rail. Requires C1 to
decouple the input rail. Connect using a wide PCB trace.
2
3
IN
SW
Switch Output. Connect using a wide PCB trace.
System Ground. This pin is the reference ground of the regulated output voltage, and
PCB layout requires special care. For best results, connect to GND with copper traces
and vias.
4
5
GND
BST
Bootstrap. Requires a capacitor connected between SW and BST pins to form a floating
supply across the high-side switch driver. A 10Ω resistor placed between SW and BST
cap is strongly recommended to reduce SW spike voltage.
Enable/Synchronize. EN high to enable the MP1495S. Apply an external clock to the EN
pin to change the switching frequency.
6
7
EN/SYNC
VCC
Bias Supply. Decouple with 0.1μF-to-0.22μF capacitor. Select a capacitor that does not
exceed 0.22μF. VCC capacitor should be put closely to VCC pin and GND pin.
Feedback. Connect to the tap of an external resistor divider from the output to GND, to
set the output voltage. The frequency fold-back comparator lowers the oscillator
frequency when the FB voltage is below 400mV to prevent current limit runaway during a
short-circuit fault condition.
8
FB
MP1495S Rev. 1.0
12/13/2013
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