| 1, 2, 3, 4, 5 | SWO | Switch (Output): This is the output of the PFM
Switcher. |
| 6, 23, 24, 25, 26, 27, 28 | SW | Switch Node: Attach external resistor from LPF to
increase hysteric frequency. |
| 7, 22 | EPAD | Exposed Heat-sink Pad. Connect externally to
PGND. |
| 8 | AVIN | Analog Supply Voltage: Supply for the analog control
circuitry. Requires bypass capacitor to ground. Nominal bypass capacitor is 1
μF. |
| 9 | LPF | Low Pass Filter: Attach external resistor from SW to
increase hysteretic frequency. |
| 10 | AGND | Analog Ground. |
| 11 | FB | Feedback: Input to the error amplifier. Connect to
the external resistor divider network to set the output voltage. |
| 12, 13 | LDOOUT | LDO Output: Output of voltage regulator. Place
capacitor to ground to bypass the output voltage. Nominal bypass capacitor is 10
μF. |
| 14, 15 | LDOIN | LDO Input: Connect to SW output. Requires a bypass
capacitor to ground. Nominal bypass capacitor is 10 μF. |
| 16, 17 | PVIN | Input Supply Voltage (Input): Requires bypass
capacitor to GND. Nominal bypass capacitor is 10 μF. |
| 18 | EN | Enable (Input): Logic low will shut down the device,
reducing the quiescent current to less than 50 μA. This pin can also be used as an
under-voltage lockout function by connecting a resistor divider from EN pin-to-VIN and
GND. It should be not left open. |
| 19, 20, 21 | PGND | Power Ground. |
