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VB326SP
ELECTRICAL CHARACTERISTICS (continued)
Symbol Parameter Test Conditions Min Typ Max Unit
I
EH
High Level Sinked Enable
Current
V
E
=5V 500 µA
I
EL
Low Level Sinked Enable
Current
V
E
<0.4V - 200 µA
V
BD(off)
Base Darlington Voltage Off V
E
=V
EH
1V
V
BD(on)
Base Darlington Voltage On V
IN
=V
INH
; V
E
=V
EL
; I
C
=6.5A 1.8 V
1
PRINCIPLE OF OPERATION
The VB326SP is mainly intended as a high voltage
power switch device driven by a logic level input
and interfaces directly to a high energy electronic
ignition coil.
The input V
IN
of the VB326SP is fed from a low
power signal generated by an external controller
that determinesboth dwell time and ignition point.
During Vin high (≥ 4V) the VB326SP increases
current in the coil to the desired, internally set
current level.
After reaching this level, the coil current remains
constant until the ignition point, that corresponds
to the transition of Vin from high to low (typ. 1.9V
threshold).
During the coil current switch-off, the primary
voltage HV
C
is clamped at an internally set value
V
cl
, typically 380V. The transition from saturation
to desaturation, coil current limiting phase, must
have the ability to accomodate an overvoltage.
A maximum overshoot of 20V is allowed.
FEEDBACK
When the collector current exceeds 6.5A, the
feedback signal is turned high and it remains so,
until the input voltage is turned-off.
OVERVOLTAGE
The VB326SP can withstand the following
transients of the battery line:
-100V/2msec(R
i
=10 Ω)
+100V/0.2msec (R
i
=10 Ω)
+50V/400msec (R
i
= 4.2 Ω, with V
IN
= 3V)
Figure 1: Flag current Vs. temperature Figure 2: Single pulse avalanche energy capability
0
50
100
150
200
250
300
350
400
450
500
550
600
650
700
0 102030405060708090100110
L (mH)
E (mJ)
Tc=25º
Tc=150º
Obsolete Product(s) - Obsolete Product(s)
