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L6712A L6712

The device offers a bi-directional pin REF_IN/OUT: the internal reference used for the regulation is usually

available on this pin with 3mA of maximum current capability except when VID code 111 is programmed;

in this case the device accepts an external reference through the REF_IN/OUT pin and regulates on it.

When external reference is used, it must range from 0.800V up to 3.300V to assure proper functionality of

the device.

Figure 2 shows a block schematic of how the Reference for the regulation is managed when internal or

external reference is used.

The voltage identification (VID) pin configuration or the external reference provided also sets the power-

good thresholds (PGOOD) and the Over/Under voltage protection (OVP/UVP) thresholds.

Figure 2. Reference Management

The output regulated voltage accuracy can be extracted from the following relationships (worst case con-

dition):

(worst case with internal reference)

(worst case with external reference)

tion (see relevant section).

A statistical analysis could consider applying the root-sum-square (RSS) method to calculate the precision

since all the variables are statistically independent as follow:

(with internal reference)

BAND-GAP

REFERENCE

(1.235V)

DAC

VID3

VID2

VID1

REF_IN/OUT

CONTROL

LOGIC

VIDx

DIGITAL

SOFT-START

ERROR

AMPLIFIER

FB

COMP

INTERNAL REFERENCE

EXTERNAL REFERENCE

V

[]

V

[] K

OS

V

OS_RA

V

OUT

-------------------- 100

⋅⋅

+

0.9%

±

() K

OS

8mV

±

()

V

OUT

--------------------- 100

⋅⋅

+

==

V

[] EXT_REF_Accuracy[%]

V

PR O G

REF_IN/OUT

------------------------------------- [%]

V

OS_EA

EXT_REF

--------------------------- 100

⋅





K

OS

V

OS_RA

V

OUT

-------------------- 100=

⋅⋅

++

+

=

EXT_REF_Accuracy[%]

2.0%

±

()

5mV

±

()

EXT_REF

--------------------------- 100

⋅





K

OS

8mV

±

()

V

out

--------------------- 100

⋅⋅

++

+

=

V

V

()

2

K

OS

V

OS_RA

V

OUT

-------------------- 100

⋅⋅





+

2

=