Microchip Technology TC1303BDM-DDBK1 Data Sheet
TC1303A/TC1303B/TC1303C/TC1304
DS21949C-page 20
© 2008 Microchip Technology Inc.
3.8
Buck Regulator Shutdown Input
Pin (SHDN1)
Pin (SHDN1)
SHDN1 is a logic-level input used to turn the buck
regulator on and off. A logic-high (> 45% of V
regulator on and off. A logic-high (> 45% of V
IN
), will
enable the regulator output. A logic-low (< 15% of V
IN
)
will ensure that the output is turned off.
3.9
Buck Regulator Input Voltage Pin
(V
(V
IN1
)
V
IN1
is the buck regulator power input supply pin.
Connect a variable input voltage source to V
IN1
.
Connect V
IN1
and V
IN2
together with board traces as
short as possible.
3.10
Buck Inductor Output Pin (L
X
)
Connect L
X
directly to the buck inductor. This pin
carries large signal-level current; all connections
should be made as short as possible.
should be made as short as possible.
3.11
Power Ground Pin (P
GND
)
Connect all large-signal level ground returns to P
GND
.
These large-signal, level ground traces should have a
small loop area and length to prevent coupling of
switching noise to sensitive traces. Please see the
physical layout information supplied in Section 5.0
“Application Circuits/Issues” for grounding
recommendations.
small loop area and length to prevent coupling of
switching noise to sensitive traces. Please see the
physical layout information supplied in Section 5.0
“Application Circuits/Issues” for grounding
recommendations.
3.12
Exposed Pad (EP)
For the DFN package, connect the EP to A
GND
, with
vias into the A
GND
plane.