Datasheet

Application ideas L7986TA
38/43 Doc ID 022098 Rev 3
The GND pin of the device is connected to the output voltage so, given the output voltage,
input voltage range is limited by the maximum voltage the device can withstand across VCC
and GND (38 V). Therefore, if the output is -5 V the input voltage can range from 4.5 V to 33
V.
As in the positive buck-boost, the maximum output current according to application
conditions is shown in Figure 36. The dashed line considers a more accurate estimation of
the duty cycles given by Equation 46, where power losses across diodes and the internal
power MOSFET are taken into account.
Equation 46
Figure 36. Maximum output current according to switch max. peak current (3.0 A):
V
O
=-5 V
D
V
OUT
V
D
–
V–
IN
V
SW
V
OUT
V
D
–+–
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