L6928

Pin settings

3/16

1

Pin settings

1.1

Pin connection

Figure 1.

Pin connection (top view)

1.2

Pin description

RUN

COMP

VFB

GND

1

3

2

4LX

SYNC

PGOOD

8

7

6

5

D01IN1239AMOD

Table 1. Pin description

Pin N°

Name

Description

1RUN

Shutdown input. When connected to a low level (lower than 0.4V) the device

stops working. When high (higher than 1.3V) the device is enabled.

2COMP

Error amplifier output. A compensation network has to be connected to this pin.

Usually a 220pF capacitor is enough to guarantee the loop stability.

3VFB

Error amplifier inverting input. The output voltage can be adjusted from 0.6V up

to the input voltage by connecting this pin to an external resistor divider.

4

GND

Ground.

5LX

Switch output node. This pin is internally connected to the drain of the internal

switches.

6VCC

Input voltage. The start up input voltage is 2.2V (typ) while the operating input

voltage range is from 2V to 5.5V. An internal UVLO circuit realizes a 100mV

(typ.) hysteresis.

7

SYNC

Operating mode selector input. When high (higher than 1.3V) the Low

Consumption Mode is selected. When low (lower than 0.5V) the Low Noise

Mode is selected. If connected with an appropriate external synchronization

signal (from 500KHz up to 1.4MHz) the internal synchronization circuit is

activated and the device works at the same switching frequency.

8

PGOOD

Power good comparator output. It is an open drain output. A pull-up resistor

should be connected between PGOOD and VOUT (or VCC depending on the

requirements). The pin is forced low when the output voltage is lower than 90%

of the regulated output voltage and goes high when the output voltage is greater

than 90% of the regulated output voltage. If not used the pin can be left floating.