Datasheet

ADP2441 Data Sheet
Rev. A | Page 6 of 32
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
FB
COMP
NOTES
1. THE EXPOSED PAD SHOULD BE CONNECTED
TO THE SYSTEM AGND PLANE AND PGND PLANE.
EN
VIN
SW
PGND
PGOOD
FREQ
SS/TRK
AGND
VCC
BST
10581-003
9
8
7
1
2
3
4
5
6
12
11
10
TOP
VIEW
ADP2441
Figure 3. Pin Configuration, Top View
Table 4. Pin Function Descriptions
Pin No. Mnemonic Description
1 FB Feedback 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 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 low to disable the regulator. Do not leave the EN 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 the FREQ pin floating.
6 SS/TRK
Soft Start/Tracking Input. A capacitor to ground is required to program the soft start time, which gradually ramps
up the output. A resistive divider to an external reference is required on this pin to track an external voltage.
7 PGND
Power Ground. Connect a decoupling ceramic capacitor as close as possible between the VIN pin and this pin.
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 needed 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 μF 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 directly to the exposed pad.
EP Exposed Thermal Pad. The exposed pad should be connected to AGND and PGND.