Datasheet

UCC27423-Q1
GND
1
2
3
4
INB
INA
7
6
5
8
OUTA
VDD
OUTB
INPUT
CER
AL EL
VDD
C2 C3
+
5.5 V
ENBB
ENBA
100 mF
1 mF
0.1 W
100 mF
1 mF
VSNS
DADJ
RSNS
DSCHOTTKY
10 W
UCC27423-Q1
GND
1
2
3
4
INB
INA
7
6
5
8
OUTA
VDD
OUTB
INPUT
CER
AL EL
VDD
C2 C3
+
5.5 V
ENBB
ENBA
100 mF
1 mF
0.1 W
100 mF
1 mF
VSNS
VSUPPLY
RSNS
DSCHOTTKY
10 W
UCC27423-Q1
UCC27424-Q1
UCC27425-Q1
www.ti.com SGLS274F –SEPTEMBER 2008–REVISED SEPTEMBER 2012
Two circuits are used to test the current capabilities of the UCC27423-Q1 driver. In each case external circuitry is
added to clamp the output near 5 V while the IC is sinking or sourcing current. An input pulse of 250 ns is
applied at a frequency of 1 kHz in the proper polarity for the respective test. In each test there is a transient
period where the current peaked up and then settled down to a steady-state value. The noted current
measurements are made at a time of 200 ns after the input pulse is applied, after the initial transient.
The circuit in Figure 29 is used to verify the current sink capability when the output of the driver is clamped
around 5 V, a typical value of gate-source voltage during the Miller plateau region. The UCC27423-Q1 is found
to sink 4.5 A at V
DD
= 15 V and 4.28 A at V
DD
= 12 V.
Figure 29. Current Sinking
The circuit shown in Figure 30 is used to test the current source capability with the output clamped to around 5 V
with a string of Zener diodes. The UCC27423-Q1 is found to source 4.8 A at V
DD
= 15 V and 3.7 A at V
DD
= 12
V.
Figure 30. Current Sourcing
The current sink capability is slightly stronger than the current source capability at lower V
DD
. This is due to the
differences in the structure of the bipolar-MOSFET power output section, where the current source is a P-
channel MOSFET and the current sink has an N-channel MOSFET.
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