Data Sheet

PROFET
®
BTS 6133D
Data Sheet Page 11 of 17 Rev. 1.0, 2007-02
Short circuit detection
Fault Condition: V
ON
> V
ON(SC)
(3.5 V typ.) and t> t
d(SC)
(typ.650 µs).
Overload detection
Fault Condition: V
ON
> 1 V typ.
detection
circuit
Logic
unit
+ V
bb
OUT
V
ON
Short circuit
Short circuit is a combination of primary and
secondary impedance’s and a resistance’s.
PROFET
V
IN
OUT
IS
bb
R
SC
I
IN
V
bb
Z
L
SC
L
SC
10mOhm
5uH
Allowable combinations of minimum, secondary
resistance for full protection at given secondary
inductance and supply voltage for single short circuit
event
:
0
5
16V
10
0 100 200
R
SC
[mOhm]
15
L
SC
300
[uH]
V :
bb
18V
24V
30V
Inductive load switch-off energy
dissipation
PROFET
V
IN
OUT
IS
bb
E
E
E
E
AS
bb
L
R
E
Load
L
R
L
{
Z
L
R
IS
I
IN
V
bb
i (t)
L
Energy stored in load inductance:
E
L
=
1
/
2
·L·I
2
L
While demagnetising load inductance, the energy
dissipated in PROFET is
E
AS
= E
bb
+ E
L
- E
R
=
∫
V
ON(CL)
·i
L
(t) dt,
with an approximate solution for R
L
> 0
Ω:
E
AS
=
I
L
· L
2
·R
L
(V
bb
+ |V
OUT(CL)
|) ln (1+
I
L
·R
L
|V
OUT(CL)
|
)
Maximum allowable load inductance for
a single switch off
L = f (I
L
); T
j,start
=
150°C, V
bb
= 12 V, R
L
= 0 Ω
0,01
0,1
1
10
100
1000
110100
I_L [A]
L [mH]