L6712QTR STMicroelectronics, L6712QTR Datasheet - Page 10

• Manufacturer Part Number: L6712QTR
• Description: IC CTRLR DC/DC 2PH SYNC 36VFQFPN
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L6712QTR

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 0.9 ~ 3.3 V
• Current - Output: 2A
• Frequency - Switching: 150kHz
• Voltage - Input: 12V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 36-VFQFN, 36-VFQFPN
• Power - Output: 3.5W
• Operating Temperature Range: - 40 C to + 125 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-4219-2

L6712A L6712
Figure 6. Reference Management
The output regulated voltage accuracy can be extracted from the following relationships (worst case con-
dition):
where V
tively and K
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:
10/29
V
OUT_TOT_ACC
V
OUT_TOT_ACC
OS_RA
REF_IN/OUT
V
OS
OUT_TOT_ACC
[%] =
VID3
VID2
VID1
and V
= 1+1/RA_Gain reflects the impact of the Remote Amplifier Gain (RA_Gain) on the regula-
=
[ ]
%
EXT_REF_Accuracy[%]
(
OS_EA
=
EXT_REF_Accuracy[%]
EXT_REF_Accuracy[%]
V
[ ]
OUT_TOT_ACC
%
REFERENCE
are the offsets related to the Error Amplifier and the Remote Amplifier respec-
BAND-GAP
(1.235V)
=
DAC
V
OUT_ACC
(worst case with external reference)
(worst case with internal reference)
[%]
(with external reference)
(with internal reference)
[ ]
=
%
+
± (
)
2
(
+
SOFT-START
+
2.0%
V
+
CONTROL
K
⎛
⎝
OUT_ACC
DIGITAL
------------------------------------ - [%]
REF_IN/OUT
------------------------------------ - [%]
REF_IN/OUT
LOGIC
OS
)
V
V
⋅
+
V
-------------------- 100
PROG
PROG
V
⎛
⎝
OS_RA
-------------------------- - 100
EXT_REF
OUT
± (
[%]
5mV
)
2
⋅
+
)
⎛
⎝
K
⎞
⎠
VIDx
+
⋅
OS
2
=
⎛
⎝
+
-------------------------- - 100
EXT_REF
⎛
⎝
V
± (
⋅
V
-------------------------- - 100
EXT_REF
PROG
⎞
⎠
V
-------------------- 100
OS_EA
V
0.9%
V
+
OS_RA
OS_EA
OUT
K
OS
)
+
⋅
⋅
⋅
± (
-------------------- - 100
K
⋅
OS
INTERNAL REFERENCE
EXTERNAL REFERENCE
V
8mV
FB
out
⎞
⎠
⎞
⎠
AMPLIFIER
⋅
2
⎞
⎠
+
± (
-------------------- - 100
2
ERROR
K
)
V
+ K
8mV
⋅
OS
OUT
⎛
⎝
OS
⋅
V
-------------------- 100=
)
V
⋅
OS_RA
⋅
OUT
V
-------------------- 100
COMP
V
OS_RA
OUT
⋅
⋅
⎞
⎠
2