EVAL6730 STMicroelectronics, EVAL6730 Datasheet - Page 19

• Manufacturer Part Number: EVAL6730
• Description: EVAL BOARD FOR L6730XX
• Manufacturer: STMicroelectronics
• Type: Motor / Motion Controllers & Driversr

Specifications of EVAL6730

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Power - Output: 66W
• Voltage - Output: 3.3V
• Current - Output: 20A
• Voltage - Input: 4.5 ~ 14V
• Regulator Topology: Buck
• Frequency - Switching: 400kHz
• Board Type: Fully Populated
• Utilized Ic / Part: L6730
• Input Voltage: 8 V to 52 V
• Product: Power Management Modules
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: L6208
• Other names: 497-5501

Figure 19. Over Current Operation.
The maximum value reached by the current depends on its slew-rate, so on the short circuit nature and supply
voltage, and on the total intervention delay (t
imum value reached by the output current becomes lower, because the capacitor on EN pin is discharged start-
ing from a lower voltage, resulting in a shorter t
The following approximate relations estimate the disable time and the first OCD intervention delay after the short
circuit (worst case).
The time the device remains disabled is:
where
V
The total intervention time is
where
t
OCD(OFF)
EN(LOW)
I
S OVER
t
OCD(ON)
V
, t
is the minimum voltage reached by the EN pin, and can be estimated with the relation:
TH(OFF)
OCD(ON)
t
OCD(OFF)
t
DELAY
, t
D(ON)EN
t
EN(FALL)
t
, t
D(OFF)EN
D(OFF)EN
V
t
EN RISE
Output Current
EN LO W
t
t
EN FAL L
DISABLE
t
t
DELAY
DISABLE
, and R
EN
= t
= t
=
=
OCD(ON)
DELAY
=
OCD(OFF)
R
V
OPDR
DELAY
EN
T H O FF
R
OPDR
). It can be noticed that after the first current peak, the max-
C
are device intrinsic parameters, V
+ t
.
EN
+ t
EN(FALL)
C
EN(RISE)
e
ln
EN
t
---------------------------------------------------------- -
D OFF EN
V
-------------------------------------------- -
V
DD
DD
R
ln
+ t
OP DR
V
–
V
+ t
-------------------------
V
t
TH(ON)
–
DISABLE
D(OFF)EN
EN(LOW)
V
TH O FF
V
+
D(ON)EN
V
E N L O W
t
TH O N
O CD OFF
DD
C
EN
AN1451 APPLICATION NOTE
t
D(ON)EN
t
EN(RISE)
Output Current
DD
is the pull-up voltage
EN
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