BTM7745G Datasheet, PDF (21/24 Pages) Infineon Technologies AG – High Current H-Bridge Trilith IC 3G

High Current H-Bridge
BTM7745G
Application Information
It is recommended to do the freewheeling in the low side path to ensure a proper function and avoid unintended
overtemperature detection and shutdown. For proper operation it is also recommended to put a pull-down resistor
R_Dx on each output OUTx to GND with a value in the range of e.g. 1...10 kΩ. These resistors can also be used for
open load detection.
Considerations for Open Load Detection Mode
As mentioned in Chapter 6.4.1 both high side switches can be switched on independently while all other switches
are off. This will be realized by setting the corresponding IN signal to high while INH and the other IN are low.
Device State
Inputs
Outputs
INH IN1 IN2 HS1 LS1 HS2 LS2 ST
Open-Load detection 0 0
1
OFF OFF ON OFF 1
mode
01 0
ON OFF OFF OFF 1
01
1
ON OFF ON OFF 1
Mode
HS2 active
HS1 active
both HSx are active
Together with the recommended pull-down resistors on the outputs OUTx to GND this provides the possibility to
do an open load detection in H-bridge configuration.
In case of one high side is active while the other half bridge is off (HS off and LS off) a current of up to 2mA will
be sourced out of the OUT of the high ohmic half bridge. This has to be considered while choosing the right value
of the pull-down resistor.
Data Sheet
21
Rev. 1.0, 2010-05-28