03541

5/29/2009

Rev:A

EP5358LUI/EP5358HUI

©Enpirion 2009 all rights reserved, E&OE

12

www.enpirion.com

()

Rb

Ra

OUT

V

V

+

=

1

6

.

0

10

μF

0603

2.2uF

0603

AGND

ENABLE

Ra

Rb

PGND

AVIN

PVIN

Figure 8: EP5358LUI using external divider

Ω

−

=

6

.

0

10

2

.

142

3

OUT

b

V

x

R

NOTE:

Dynamic Voltage Scaling is not allowed

between internal preset voltages and external

divider.

EP5358HUI High VID Range Programming

for higher nominal voltages such as those

required to power IO, RF, or IC memory. The

preset voltages range from 1.8V to 3.3V.

There are eight (8) preset output voltage

settings. The EP5358HUI does not have an

external

divider

option.

As

with

the

EP5358LUI, the VID pin settings can be

changed while the device is enabled.

Table 2 shows the VS0-VS2 pin logic states for

the EP5358HUI and the associated output

voltage levels.

A logic “1” indicates a

connection to AVIN or to a “high” logic voltage

level.

A logic “0” indicates a connection to

AGND or to a “low” logic voltage level. These

pins can be either hardwired to AVIN or AGND

or alternatively can be driven by standard logic

levels. Logic levels are defined in the electrical

characteristics table. Any level between the

logic high and logic low is indeterminate.

These pins must not be left floating.

Table 2: EP5358HUI VID Voltage Select Settings

VS2

VS1

VS0

VOUT

00

0

3.3

00

1

3.0

01

0

2.9

01

1

2.6

10

0

2.5

10

1

2.2

11

0

2.1

11

1

1.8

Input Filter Capacitor

The input filter capacitor requirement is a

2.2µF 0603 low ESR MLCC capacitor. The

input capacitor must use a X5R or X7R or

equivalent dielectric formulation.

Y5V or

equivalent

dielectric

formulations

lose

capacitance with frequency, bias, and with

temperature, and are not suitable for switch-

mode DC-DC converter input filter applications.

Output Filter Capacitor

The output filter capacitor requirement is a

minimum of 10µF 0603 MLCC for VIN<4.3V

and 10uF 0805 for VIN>4.3V.

Ripple

performance can be improved by using 2x10µF

0603 MLCC capacitors (for any allowed VIN).

The maximum output filter capacitance next to

the output pins of the device is 60µF low ESR

the last output filter capacitor next to the

EP5358xUI.

Additional bulk capacitance for decoupling and

bypass can be placed at the load as long as

Sense point and the bulk capacitance.

Excess total capacitance on the output (Output

Filter + Bulk) can cause an over-current

condition at startup. Refer to the section on

Soft-Start for the maximum total capacitance

on the output.

The output capacitor must use a X5R or X7R

or equivalent dielectric formulation.

Y5V or

equivalent

dielectric

formulations

lose

capacitance

with

frequency,

bias,

and

temperature and are not suitable for switch-

mode

DC-DC

converter

output

filter

applications.