Ericsson Internal
PRODUCT SPECIFICATION
3 (4)
Prepared (also subject responsible if other)
No.
SEC/D ESECZHW
3/1301-BMR643 8/M Uen
Approved
Checked
Date
Rev
Reference
SEC/D LINDA
ESKEVIN
2006-2-27
A
Thermal Consideration continued
Definition of reference temperature (Tref)
The reference temperature is used to monitor the temperature
limits of the product. Temperatures above maximum Tref are
not allowed and may cause degradation or permanent
damage to the product. Tref is also used to define the
temperature range for normal operating conditions.
Tref is defined by the design and used to guarantee safety
margins, proper operation and high reliability of the module.
Ambient Temperature Calculation
TBD
Thermal Consideration
General
The 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 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 DC/DC 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 DC/DC 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 Tref +85°C.
See Design Note 019 for further information.
Position
Device
Designation
max value
P1
PCB
110 C
P2
MOSFET
Tref
120 C
P3
INDUCTOR
120 C
Connections
v F
TOP VIEW
Pin
Designation
Function
1
GND
Common ground connection for the Vin
and VTT power connections.
2
VIN
The positive input voltage power node to
the module.
3
Inhibit
Applying a low-level ground signal to this
input disables the module’s output.
4
No Connect
5
VoSENSE
The Vo sense allows the regulation circuit
to compensate for voltage drop between
the module and load. For optimal voltage
accuracy Vo Sense should be connected
to VTT.
6
VTT
Regulated power output with respect to
the GND node and required bus
termination supply voltage.
7
GND
Common ground connection for the Vin
and VTT power connections.
8
VREF
Reference voltage for the system bus
receiver comparators.
9
No Connect
10
No Connect
E
PMF 8000F series
POL regulator, Input 10.8-13.2 V, Output 10 A/18 W
EN/LZT 146 333 R1B April 2006
Ericsson Power Modules AB
Technical Specication
E
PMF 8000F series
POL regulator, Input 10.8-13.2 V, Output 10 A/18 W
EN/LZT 146 333 R1C April 2007
Ericsson Power Modules AB
Technical Specication
10