Datasheet

ADP2442 Data Sheet
Rev. 0 | Page 6 of 36
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
Figure 3. Pin Configuration, Top View
Table 4. Pin Function Descriptions
Pin No. Mnemonic Description
1 FB Feedback. The FB regulation voltage is 0.6 V. Connect this pin to a resistor divider from the output of the dc-to-dc
regulator.
2
COMP
Error Amplifier Compensation. Connect a resistor and a capacitor in series to ground.
3 EN Precision Enable. This features offers ±5% accuracy when using a 1.25 V reference voltage. Pull this pin high to
enable the regulator and pull it low to disable the regulator. Do not leave this pin floating.
4 PGOOD Active High Power Good Output. This pin is pulled low when the output is out of regulation.
5 FREQ Switching Frequency. A resistor to AGND sets the switching frequency (see the Setting the Switching Frequency
section). Do not leave this pin floating.
6
SYNC/MODE
External Clock Synchronization/Mode Pin. This pin can be used for external frequency synchronization and for
setting forced fixed frequency mode or pulse skip mode. SYNC/MODE accepts an external clock signal, and when
pulled high to 5 V, it sets the mode as forced fixed frequency mode. When this pin is tied to AGND, pulse skip
mode is enabled. Do not leave the SYNC/MODE pin floating.
7 PGND Power Ground. Connect a decoupling ceramic capacitor as close as possible between the VIN pin and PGND.
Connect this pin directly to the exposed pad.
8 SW Switch. The midpoint for the drain of the low-side N-channel power MOSFET switch and the source for the high-
side N-channel power MOSFET switch.
9 VIN Power Supply Input. Connect this pin to the input power source, and connect a bypass ceramic capacitor directly
from this pin to PGND, as close as possible to the IC. The operation voltage is 4.5 V to 36 V.
10 BST Boost. Connect a 10 nF ceramic capacitor between the BST and SW pins as close to the IC as possible to form a
floating supply for the high-side N-channel power MOSFET driver. This capacitor is required to drive the gate of
the N-channel power MOSFET above the supply voltage.
11 VCC Output of the Internal Low Dropout Regulator. This pin supplies power for the internal controller and driver
circuitry. Connect a 1 µF ceramic capacitor between VCC and AGND and a 1 µ F ceramic capacitor between VCC
and PGND. The VCC output is active when the EN pin voltage is more than 0.7 V.
12
AGND
Analog Ground. This pin is the internal ground for the control functions. Connect this pin to the exposed pad.
EP Exposed Pad. Connect the exposed pad to the system AGND plane and PGND plane.
FB
COMP
EN
VIN
SW
PGND
PGOOD
FREQ
SYNC/MODE
AGND
VCC
BST
10667-003
9
8
7
1
2
3
4
5
6
12
11
10
TOP
VIEW
ADP2442
NOTES
1. THE EXPOSED PAD SHOULD BE CONNECTED
TO THE SYSTEM AGND PLANE AND PGND PLANE.