L6712A L6712

10/29

Figure 6. 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)

(with external 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

PROG

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

=

V

EXT_REF_Accuracy[%]

()

2

+

V

PROG

REF_IN/OUT

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

⎝⎠

⎛⎞

2

+

V

OS_EA

EXT_REF

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

⋅

⎝⎠

⎛⎞

2

+K

OS

V

OS_RA

V

OUT

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

⋅⋅

⎝⎠

⎛⎞

2