
Ericsson Internal
PRODUCT SPEC.
3 (5)
Prepared (also subject responsible if other)
No.
SEC/D KEVIN YAN
3/1301-BMR 652 8 Uen
Approved
Checked
Date
Rev
Reference
SEC/D Julia You
2006-12-26
B
Auto-Track Function
The AutoTrack function is designed so that 2 or more POL
regulators can track each others output voltage tightly
together. This can be accomplished by connection the
AutoTrack pin to the output of another POL regulator or by
feeding an external voltage ramp on the pin. The AutoTrack
will automatically track any external voltage that is applied
within the given rules in Application Note POLA (AN205).
Thermal Consideration
General
The POL regulators are designed to operate in different
thermal environments and sufficient cooling must be provided
to ensure reliable operation.
Cooling is achieved mainly by conduction, from the pins to
the host board, and convection, which is dependant on the
airflow across the regulator. Increased airflow enhances the
cooling of the POL regulator.
The Output Current Derating graph found in the Output
section for each model provides the available output current
vs. ambient air temperature and air velocity at Vin = 12 V.
The POL regulator is tested on a 254 x 254 mm,
35 m (1 oz), 8-layer test board mounted vertically in a wind
tunnel with a cross-section of 305 x 305 mm.
Proper cooling of the POL regulator can be verified by
measuring the temperature at positions P1, P2 and P3. The
temperature at these positions should not exceed the max
values provided in the table below.
Note that the max value is the absolute maximum rating
(non destruction) and that the electrical Output data is
guaranteed up to Tamb +85°C.
See Design Note 019 for further information.
Position
Device
Designation
max value
P1
Pcb
TBD
P2
Controller
Tref
TBD
P3
Inductor
TBD
E
PMD 5000 series
POL regulator, Input 4.5-14 V, Output 2.25 A/12.375 W
EN/LZT 146 351 R1D Dec 2006
Ericsson Power Modules AB
Technical Specication
E
PMD 5000 series
POL regulator, Input 4.5-14 V, Output 2.25 A/12.375 W
EN/LZT 146 351 R1E Jan 2009
Ericsson Power Modules AB
Technical Specication
38