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Revision 1.03

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AS1335

Datasheet - P i n o u t

4 Pinout

Pin Assignments

Figure 2. Pin Assignments (Top View)

Pin Descriptions

Table 1. Pin Descriptions

Pin

Number

Pin Name

Description

1VIN

Positive Supply Voltage. This pin must be closely decoupled to PGND with a

≥ 22µF

ceramic capacitor.

2NC

Not Connected.

3EN

Enable Input. Driving this pin above 1.4V enables the device. Driving this pin below 0.3V

puts the device in shutdown mode. In shutdown mode all functions are disabled, drawing

≤1µA supply current.

Note: This pin should not be left floating.

4POK

Power-OK Output. Open-drain output with 215ms delay. Connect a 100k

Ω pull-up resistor

not used.

LOW Signal: Out of regulation

HIGH signal: Within Regulation (after 215ms delay)

5GND

Analog Ground.

6RSI

Reset Input for POK. This input resets the 215ms timer of the POK signal.

As long as RSI is low the POK signal will work as described above.

A high input to RSI will reset the 215ms POK timer and delay the signal as long as RSI

stays high. A RSI low-to-high transition restarts the 215ms counter as long as the output

voltage is within regulation.

Note: Do not leave this pin floating.

7FB

Feedback Pin. Feedback input to the gm error amplifier. Connect a resistor divider tap to

8GND

Analog Ground. GND and PGND should only have one point connection.

9PGND

Power-Ground. Connect all power grounds to this pin.

10

SW

Switch Node Connection to Inductor. This pin connects to the drains of the internal main

and synchronous power MOSFET switches.

11

Exposed Pad. The exposed pad must be connected to PGND. Ensure a good connection

to the PCB to achieve optimal thermal performance.

AS1335

4

POK

3

EN

2

NC

1

VIN

7 FB

9 PGND

10 SW

8GND

5

GND

6RSI

11