a5975d STMicroelectronics, a5975d Datasheet - Page 26

• Manufacturer Part Number: a5975d
• Description: Up To 3 A Step-down Switching Regulator For Automotive Applications
• Manufacturer: STMicroelectronics

Application information
8.2
26/50
Equation 21
and it can be seen that if the inductor value decreases, the peak current (which must be
lower than the current limit of the device) increases. So, when the peak current is fixed, a
higher inductor value allows a higher value for the output current. In
manufacturers are listed.
Table 8.
Layout considerations
The layout of the switching DC-DC converters is very important to minimize noise and
interference. Power-generating portions of the layout are the main cause of noise and so
high switching current loop areas should be kept as small as possible and lead lengths as
short as possible.
High impedance paths (in particular the feedback connections) are susceptible to
interference, so they should be as far as possible from the high current paths. A layout
example is provided in
The input and output loops are minimized to avoid radiation and high frequency resonance
problems. The feedback pin connections to the external divider are very close to the device
to avoid pick-up noise. Another important issue is the ground plane of the board. As the
package has an exposed pad, it is very important to connect it to an extended ground plane
in order to reduce the thermal resistance junction-to-ambient.
Coilcraft
Coilcraft
Wurth Elektronik
Manufacturer
Inductor selection
Figure 13
MSS1260T
Doc ID 018760 Rev 1
DO3316T
WE-PD L
Series
below.
I
PK
=
I
O
+
Inductor value (µH)
ΔI
---- -
2
5.6 to 12
5.6 to 15
4.7 to 27
Table
Saturation current (A)
8, some inductor
3.5 to 4.7
3.55 to 6
3.5 to 8
A5975D