AS1330
Datasheet - Pin Assignments
4 Pin Assignments
Figure 2. Pin Assignments (Top View)
VIN
8
7
6
5
SENSE 1
FB
VOUT
SW
2
AS1330
EN 3
POK
GND
4
9
Pin Descriptions
Table 1. Pin Descriptions
Pin Number
Pin Name
Description
Sense Input. Represents the input for the Power-OK behaviour. This input can be
used to supervise the input or the output voltage via a resistor divider. If connected
to GND the POK output is related to VOUT.
1
SENSE
Feedback Pin. Feedback input to the gm error amplifier. Connect a resistor divider
tap to this pin. The output voltage can be adjusted from 1.8 to 3.3V by: VOUT =
0.8V[1 + (R1/R2)]
If the fixed output voltage version ist used, connect this pin to VOUT.
Active-High Enable Input. A logic LOW reduces the supply current to < 1µA.
Connect to pin VIN for normal operation.
2
3
FB
EN
Power-OK Output. Active-High, open-drain output indicates an out-of-regulation
condition. Connect a 100kΩ pull-up resistor to pin OUT for logic levels. Leave this
pin unconnected if the Power-OK feature is not used.
Low Level:
High Level:
Signal and Power Ground. Provide a short, direct PCB path between this pin and
the negative side of the output capacitor(s).
Switch Pin. Connect an inductor between this pin and VIN. Keep the PCB trace
lengths as short and wide as is practical to reduce EMI and voltage overshoot. If
the inductor current falls to zero, or pin EN is low, an internal 100Ω anti-ringing
switch is connected from this pin to VIN to minimize EMI.
4
5
6
POK
GND
SW
Note: An optional Schottky diode can be connected between this pin and VOUT.
Output Voltage. Bias is derived from VOUT when VOUT exceeds VIN. PCB trace
length from VOUT to the output filter capacitor(s) should be as short and wide as is
practical.
Input Voltage. The AS1330 gets its start-up bias from VIN unless VOUT exceeds
VIN, in which case the bias is derived from VOUT. Thus, once started, operation is
completely independent from VIN. Operation is only limited by the output power
level and the internal series resistance of the supply.
7
VOUT
VIN
8
9
Exposed Pad. The exposed pad must be connected to GND. Ensure a good
connection to the PCB to achieve optimal thermal performance.
www.austriamicrosystems.com/DC-DC_Step-Up/AS1330
Revision 1.04
2 - 16
AMSCO [ AMS(艾迈斯) ]
