Datasheet

LM3103

SNVS523F –SEPTEMBER 2007–REVISED APRIL 2013

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Typical Application

Connection Diagram

Figure 1. 16-Lead Plastic HTSSOP

Package Number PWP0016A

PIN DESCRIPTIONS

Pin Name Description Application Information

1, 2 VIN Input supply voltage Supply pin to the device. Nominal input range is 4.5V to 42V.

3, 4 SW Switch Node Internally connected to the source of the main MOSFET and the drain of the synchronous

MOSFET. Connect to the output inductor.

5 BST Connection for Connect a 33 nF capacitor from the SW pin to this pin. This capacitor is charged through an

bootstrap capacitor internal diode during the main MOSFET off-time.

6 AGND Analog Ground Ground for all internal circuitry other than the PGND pin.

7 SS Soft-start A 70 µA internal current source charges an external capacitor of larger than 22 nF to provide

the soft-start function.

8 NC No Connection This pin should be left unconnected.

9, 10 GND Ground Must be connected to the AGND pin for normal operation. The GND and AGND pins are not

internally connected.

11 FB Feedback Internally connected to the regulation and over-voltage comparators. The regulation setting is

0.6V at this pin. Connect to feedback resistors.

12 EN Enable pin Internal pull-up. Connect to a voltage higher than 1.6V to enable the device.

13 RON On-time Control An external resistor from the VIN pin to this pin sets the main MOSFET on-time.

14 VCC Startup regulator Nominally regulated to 6V. Connect a capacitor of larger than 1 µF between the VCC and

Output AGND pins for stable operation.

15, 16 PGND Power Ground Synchronous MOSFET source connection. Tie to a ground plane.

DAP EP Exposed Pad Thermal connection pad. Connect to the ground plane.

These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam

during storage or handling to prevent electrostatic damage to the MOS gates.

Product Folder Links: LM3103