Limited Internal
TABLE OF CONTENTS 1 (1)
Prepared (also subject responsible if other) No.
SEC/D Kevin Chen 00152-EN/LZT146 382
Approved Checked Date Rev Reference
SEC/D Julia You 2007-6-21 A
Contents
General Information ............................................................. 2
Safety Specification ............................................................. 3
Absolute Maximum Ratings ............................................................. 4
Product Program Ordering No.
7.2 V/10.5 A Electrical Specification PKB 4717 PINB ................................... 5
EMC Specification ............................................................. 8
Operating Information ............................................................. 9
Thermal Consideration ........................................................... 10
Connections ........................................................... 11
Mechanical Information ........................................................... 12
Soldering Information ........................................................... 13
Delivery Information ........................................................... 13
Product Qualification Specification ........................................................... 14
Ericsson Internal
PRODUCT SPECIFICATION 1 (3)
Prepared (also subject responsible if other) No.
SEC/S Kevin Chen 1/1301-BMR636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/S Kevin Chen 2007-6-21 A
Key Features
• Industry standard Eighth-brick
58.4 x 22.7 x 8.10 mm (2.300 x 0.894 x 0.323 in.)
• High efficiency, typ. 92 % at half load
• 2250 Vdc input to output isolation
• Meets isolation requirements equivalent to basic
insulation according to IEC/EN/UL 60950
• More than 1.5 million hours predicted MTBF at +40ºC
ambient temperature
General Characteristics
• Suited for narrow board pitch applications
(15 mm/0.6 in)
• Output over voltage protection
• Input under voltage shutdown
• Over temperature protection
• Output short-circuit protection
• Remote sense
• Remote control
• Output voltage adjust function
• Highly automated manufacturing ensures quality
• ISO 9001/14001 certified supplier
• Optimized for high capacity load
Safety Approvals Design for Environment
Pending Meets requirements in high-
temperature lead-free soldering
processes.
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
Ericsson Internal
PRODUCT SPECIFICATION 2 (3)
Prepared (also subject responsible if other) No.
SEC/S Kevin Chen 1/1301-BMR636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/S Kevin Chen 2007-6-21 A
General Information
Ordering Information
See Contents for individual product ordering numbers.
Option Suffix Ordering No.
Positive Remote Control Logic
Increased stand-off height
Lead length 3.69 mm (0.145 in)
Lead length 4.57 mm (0.180 in)
P
M
LA
LB
PKB 4717 PIPNB
PKB 4717 PINBM
PKB 4717 PINBLA
PKB 4717 PINBLB
Note: As an example a positive logic, increased standoff, short pin product
would be PKB 4717 PIPNBMLA.
Reliability
The Mean Time Between Failure (MTBF) is calculated at full
output power and an operating ambient temperature (TA) of
+40°C, which is a typical condition in Information and
Communication Technology (ICT) equipment. Different
methods could be used to calculate the predicted MTBF
and failure rate which may give different results. Ericsson
Power Modules currently uses Telcordia SR332.
Predicted MTBF for the series is:
- 1.5 million hours according to Telcordia SR332, issue
1, Black box technique.
The Ericsson failure rate data system is based on field
tracking data. The data corresponds to actual failure rates
of components used in ICT equipment in temperature
controlled environments (TA = -5...+65°C).
Telcordia SR332 is a commonly used standard method
intended for reliability calculations in ICT equipment. The
parts count procedure used in this method was originally
modelled on the methods from MIL-HDBK-217F, Reliability
Predictions of Electronic Equipment. It assumes that no
reliability data is available on the actual units and devices
for which the predictions are to be made, i.e. all predictions
are based on generic reliability parameters.
Compatibility with RoHS requirements
The products are compatible with the relevant clauses and
requirements of the RoHS directive 2002/95/EC and have a
maximum concentration value of 0.1% by weight in
homogeneous materials for lead, mercury, hexavalent
chromium, PBB and PBDE and of 0.01% by weight in
homogeneous materials for cadmium.
Exemptions in the RoHS directive utilized in Ericsson
Power Modules products include:
- Lead in high melting temperature type solder (used to
solder the die in semiconductor packages)
- Lead in glass of electronics components and in
electronic ceramic parts (e.g. fill material in chip
resistors)
- Lead as an alloying element in copper alloy containing
up to 4% lead by weight (used in connection pins
made of Brass)
Quality Statement
The products are designed and manufactured in an
industrial environment where quality systems and methods
like ISO 9000, 6σ (sigma), and SPC are intensively in use to
boost the continuous improvements strategy. Infant
mortality or early failures in the products are screened out
and they are subjected to an ATE-based final test.
Conservative design rules, design reviews and product
qualifications, plus the high competence of an engaged
work force, contribute to the high quality of our products.
Warranty
Warranty period and conditions are defined in Ericsson
Power Modules General Terms and Conditions of Sale.
Limitation of Liability
Ericsson Power Modules does not make any other
warranties, expressed or implied including any warranty of
merchantability or fitness for a particular purpose
(including, but not limited to, use in life support
applications, where malfunctions of product can cause
injury to a person’s health or life).
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
2
Ericsson Internal
PRODUCT SPECIFICATION 3 (3)
Prepared (also subject responsible if other) No.
SEC/S Kevin Chen 1/1301-BMR636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/S Kevin Chen 2007-6-21 A
Safety Specification
General information
Ericsson Power Modules DC/DC converters and DC/DC
regulators are designed in accordance with safety
standards IEC/EN/UL60950, Safety of Information
Technology Equipment.
IEC/EN/UL60950 contains requirements to prevent injury
or damage due to the following hazards:
• Electrical shock
• Energy hazards
• Fire
• Mechanical and heat hazards
• Radiation hazards
• Chemical hazards
On-board DC-DC converters are defined as component
power supplies. As components they cannot fully comply
with the provisions of any Safety requirements without
“Conditions of Acceptability”. It is the responsibility of the
installer to ensure that the final product housing these
components complies with the requirements of all
applicable Safety standards and Directives for the final
product.
Component power supplies for general use should comply
with the requirements in IEC60950, EN60950 and
UL60950 “Safety of information technology equipment”.
There are other more product related standards, e.g.
IEEE802.3af “Ethernet LAN/MAN Data terminal equipment
power”, and ETS300132-2 “Power supply interface at the
input to telecommunications equipment; part 2: DC”, but
all of these standards are based on IEC/EN/UL60950 with
regards to safety.
Ericsson Power Modules DC/DC converters and DC/DC
regulators are UL60950 recognized and certified in
accordance with EN60950.
The flammability rating for all construction parts of the
products meets requirements for V-0 class material
according to IEC 60695-11-10.
The products should be installed in the end-use
equipment, in accordance with the requirements of the
ultimate application. Normally the output of the DC/DC
converter is considered as SELV (Safety Extra Low
Voltage) and the input source must be isolated by
minimum Double or Reinforced Insulation from the primary
circuit (AC mains) in accordance with IEC/EN/UL60950.
Isolated DC/DC converters
It is recommended that a slow blow fuse with a rating
twice the maximum input current per selected product be
used at the input of each DC/DC converter. If an input filter
is used in the circuit the fuse should be placed in front of
the input filter.
In the rare event of a component problem in the input filter
or in the DC/DC converter that imposes a short circuit on
the input source, this fuse will provide the following
functions:
• Isolate the faulty DC/DC converter from the input
power source so as not to affect the operation of
other parts of the system.
• Protect the distribution wiring from excessive
current and power loss thus preventing
hazardous overheating.
The galvanic isolation is verified in an electric strength test.
The test voltage (Viso) between input and output is
1500 Vdc or 2250 Vdc for 60 seconds (refer to product
specification).
Leakage current is less than 1 μA at nominal input voltage.
24 V DC systems
The input voltage to the DC/DC converter is SELV (Safety
Extra Low Voltage) and the output remains SELV under
normal and abnormal operating conditions.
48 and 60 V DC systems
If the input voltage to Ericsson Power Modules DC/DC
converter is 75 Vdc or less, then the output remains SELV
(Safety Extra Low Voltage) under normal and abnormal
operating conditions.
Single fault testing in the input power supply circuit should
be performed with the DC/DC converter connected to
demonstrate that the input voltage does not exceed
75 Vdc.
If the input power source circuit is a DC power system, the
source may be treated as a TNV2 circuit and testing has
demonstrated compliance with SELV limits and isolation
requirements equivalent to Basic Insulation in accordance
with IEC/EN/UL60950.
Non-isolated DC/DC regulators
The input voltage to the DC/DC regulator is SELV (Safety
Extra Low Voltage) and the output remains SELV under
normal and abnormal operating conditions.
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
3
Ericsson Internal
PRODUCT SPECIFICATION 1 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 2/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (LINDA ZHONG) 2007-5-15 A
Absolute Maximum Ratings
Characteristics min typ max Unit
Tref Operating Temperature (see Thermal Consideration section) -45 +110 °C
TS Storage temperature -55 +125 °C
VI Input voltage -0.5 +80 V
Viso Isolation voltage (input to output test voltage) 2250 Vdc
Vtr Input voltage transient (tp 100 ms) 100 V
Positive logic option -0.5 6 V
VRC Remote Control pin voltage
(see Operating Information section) Negative logic option -0.5 40 V
Vadj Adjust pin voltage (see Operating Information section) -0.5 2xVoi V
Stress in excess of Absolute Maximum Ratings may cause permanent damage. Absolute Maximum Ratings, sometimes referred to as no destruction limits, are
normally tested with one parameter at a time exceeding the limits of Output data or Electrical Characteristics. If exposed to stress above these limits, function and
performance may degrade in an unspecified manner.
Fundamental Circuit Diagram
Bias supply Isolated
Feedback
Primary
Driver
+ In
RC
- In
+ Out
Secondary
Driver
Control and
Supervision
+ Sense
- Sense
- Out
V
adj
Primary Secondar
y
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
4
Ericsson Internal
PRODUCT SPECIFICATION 2 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 2/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (LINDA ZHONG) 2007-5-15 A
7.2 V/10.5 A Electrical Specification PKB 4717 PINB
Tref = -40 to +90ºC, VI = 36 to 75 V, sense pins connected to output pins unless otherwise specified under Conditions.
Typical values given at: Tref = +25°C, VI= 53 VI max IO, unless otherwise specified under Conditions.
Characteristics Conditions min typ max Unit
VI Input voltage range 36 75 V
VIoff Turn-off input voltage Decreasing input voltage 30 31 35 V
VIon Turn-on input voltage Increasing input voltage 32 34 36 V
CI Internal input capacitance 3 μF
PO Output power Output voltage initial setting 0 75 W
SVR Supply voltage rejection (ac) f = 100 Hz sinewave, 1 Vp-p 66 dB
50 % of max IO 91.7
max IO 90.7
50 % of max IO, VI = 48 V 92.0
η Efficiency
max IO, VI = 48 V 90.7
%
Pd Power Dissipation max IO 7.8 9.8 W
Pli Input idling power IO = 0 A, VI = 53 V 1.7 W
PRC Input standby power VI = 53 V (turned off with RC) 0.15 W
fs Switching frequency 0-100 % of max IO (see Note 1) 200 kHz
VOi Output voltage initial setting and
accuracy Tref = +25°C, VI = 53 V, IO = 10.5 A 7.05 7.2 7.35 V
Output adjust range See operating information (see Note
2) 6 8 V
Output voltage tolerance band 10-100 % of max IO 6.98 7.42 V
Idling voltage IO = 0 A 7.05 7.35 V
Line regulation max IO 2 4 mv
VO
Load regulation VI = 53 V, 0-100 % of max IO 2 4 mv
Vtr Load transient
voltage deviation ±330 mv
ttr Load transient recovery time
VI = 53 V, Load step 25-75-25 % of
max IO, di/dt = 1 A/μs 100 μs
tr Ramp-up time
(from 10−90 % of VOi) 6.5 11.6 ms
ts Start-up time
(from VI connection to 90 % of VOi)
10-100 % of max IO
9.8 23.5 ms
max IO 0.2 ms
tf VI shut-down fall time
(from VI off to 10 % of VO) IO = 0 A 2.6 s
RC start-up time max IO 8 ms
max IO 0.2 ms
tRC RC shut-down fall time
(from RC off to 10 % of VO) IO = 0 A 2.6 s
IO Output current 0 10.5 A
Ilim Current limit threshold Tref < max Tref 14 A
Isc Short circuit current Tref = 25ºC 16 A
VOac Output ripple & noise See ripple & noise section,
max IO, VOi 50 120 mVp-p
OVP Over voltage protection Tref = +25°C, VI = 53 V, 0-100 % of
max IO 10 11 V
Note 1: Frequency may be adjusted with RT-pin. See Operating Information section.
Note 2: When input voltage is 36 V and output is trimmed up to 8V, output current can only be 20%~50% Max Io.
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
5
Ericsson Internal
PRODUCT SPECIFICATION 3 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 2/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (LINDA ZHONG) 2007-5-15 A
7.2 V/10.5 A Typical Characteristics PKB 4717 PINB
Efficiency Power Dissipation
70
75
80
85
90
95
024681012[A]
[%]
36 V
48 V
53 V
75 V
0
2
4
6
8
10
024681012[A]
[W]
36 V
48 V
53 V
75 V
Efficiency vs. load current and input voltage at Tref = +25°C Dissipated power vs. load current and input voltage at
Tref = +25°C
Output Current Derating Thermal Resistance
0
2
4
6
8
10
12
0 20 40 60 80 100 [°C]
[A]
3.0 m/s
2.5 m/s
2.0 m/s
1.5 m/s
1.0 m/s
Nat. Conv. 0
2
4
6
8
10
0.0 0.5 1.0 1.5 2.0 2.5 3.0[m/s]
[°C/W]
Available load current vs. ambient air temperature and airflow at
VI = 53 V. See Thermal Consideration section.
Thermal resistance vs. airspeed measured at the converter.
Tested in wind tunnel with airflow and test conditions as per
the Thermal consideration section.
Output Characteristics Current Limit Characteristics
7.10
7.15
7.20
7.25
7.30
024681012[A]
[V]
36 V
48 V
53 V
75 V
0.00
2.00
4.00
6.00
8.00
5 8 11 14 17 [A]
[V]
36 V
48 V
53 V
75 V
Output voltage vs. load current at Tref = +25°C
Output voltage vs. load current at IO > max IO , Tref = +25°C
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
6
Ericsson Internal
PRODUCT SPECIFICATION 4 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 2/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (LINDA ZHONG) 2007-5-15 A
7.2 V/10.5 A Typical Characteristics PKB 4717 PINB
Start-up Shut-down
Start-up enabled by connecting VI at:
Tref = +25°C, VI = 53 V,
IO = 10.5 A resistive load.
Top trace: output voltage (2V/div.).
Bottom trace: input voltage (20V/div.).
Time scale: (5ms/div.).
Shut-down enabled by disconnecting VI at:
Tref = +25°C, VI = 53 V,
IO = 10.5 A resistive load.
Top trace: output voltage (2V/div.).
Bottom trace: input voltage (50V/div.).
Time scale: (0.1ms/div.).
Output Ripple & Noise Output Load Transient Response
Output voltage ripple at:
Tref = +25°C, VI = 53 V,
IO = 10.5 A resistive load.
Trace: output voltage (20mV/div.).
Time scale: (2μs/div.).
Output voltage response to load current step-
change (2.5-7.5-2.5 A) at:
Tref =+25°C, VI = 53 V.
Top trace: output voltage (200mV/div.).
Bottom trace: load current (5A/div.).
Time scale: (0.1ms/div.).
Output Voltage Adjust (see operating information)
Passive adjust
The resistor value for an adjusted output voltage is calculated by
using the following equations:
Output Voltage Adjust Upwards, Increase:
()
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛−
×−×
−×
=22.10
2.7225.1225.1 225.12.711.5
out
out
VV
Radj kΩ
Output Voltage Adjust Downwards, Decrease:
()
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
−
−×
=
out
out
V
V
Radj 2.7 2.7211.5 kΩ
Example: Upwards =>Vout = 7.85 Vdc
()
⎟
⎠
⎞
⎜
⎝
⎛−
×−×
−× 22.10
2.7225.185.7225.1 225.185.72.711.5 kΩ = 296 kΩ
Active adjust
The output voltage may be adjusted using a voltage applied to the
Vadj pin. This voltage is calculated by using the following equations:
⎟
⎠
⎞
⎜
⎝
⎛−
×+= 2.7 2.7
45.2225.1 Vdesired
Vadj V
Example: Upwards => 7.85 V
⎟
⎠
⎞
⎜
⎝
⎛−
×+ 2.7 2.785.7
45.2225.1 V = 1.45 V
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
7
Ericsson Internal
PRODUCT SPECIFICATION 1 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 3/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (Julia You) ECHWANG 2007-6-18 A
EMC Specification
Conducted EMI measured according to EN55022, CISPR 22
and FCC part 15J (see test set-up). See Design Note 009 for
further information. The fundamental switching frequency is
200 kHz for PKB 4717 PINB @ VI = 53 V, max IO.
Conducted EMI Input terminal value (typ)
EMI without filter
External filter (class B)
Required external input filter in order to meet class B in
EN 55022, CISPR 22 and FCC part 15J.
Filter components:
C1,2,6 = 1 μF/100 V
Ceramic
C3, 4 = 2.2 nF/1500 V
Ceramic
C5 = 100 μF/100 V
Electrolytic
L1,L2 = 1.47 mH
2.8 A, Common Mode
EMI with filter
Test set-up
Layout recommendation
The radiated EMI performance of the DC/DC converter will
depend on the PCB layout and ground layer design.
It is also important to consider the stand-off of the DC/DC
converter.
If a ground layer is used, it should be connected to the output
of the DC/DC converter and the equipment ground or
chassis.
A ground layer will increase the stray capacitance in the PCB
and improve the high frequency EMC performance.
Output ripple and noise
Output ripple and noise measured according to figure below.
See Design Note 022 for detailed information.
Output ripple and noise test setup
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
8
Ericsson Internal
PRODUCT SPECIFICATION 2 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 3/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (Julia You) ECHWANG 2007-6-18 A
Operating information
Input Voltage
The input voltage range 36 to 75Vdc meets the requirements
{of the European Telecom Standard ETS 300 132-2 for
normal input voltage range in —48 and —60 Vdc systems, -40.5
to -57.0 V and —50.0 to -72 V respectively.
At input voltages exceeding 75 V, the power loss will be
higher than at normal input voltage and Tref must be limited to
absolute max +110°C. The absolute maximum continuous
input voltage is 80 Vdc.
Turn-off Input Voltage
The DC/DC converters monitor the input voltage and will turn
on and turn off at predetermined levels.
The minimum hysteresis between turn on and turn off input
voltage is 1V.
Remote Control (RC)
The products are fitted with a
remote control function referenced
to the primary negative input
connection (- In), with negative
logic option available. The RC
function allows the converter to be
turned on/off by an external device
like a semiconductor or mechanical
switch. The RC pin has an internal
pull up resistor to + In.
The maximum required sink current is 1 mA. When the RC pin
is left open, the voltage generated on the RC pin is
12 — 15 V.
See Design Note 021 for detailed information.
Input and Output Impedance
The impedance of both the input source and the load will
interact with the impedance of the DC/DC converter. It is
important that the input source has low characteristic
impedance. The converters are designed for stable operation
without external capacitors connected to the input or output.
The performance in some applications can be enhanced by
addition of external capacitance as described under External
Decoupling Capacitors. If the input voltage source contains
significant inductance, the addition of a 100 μF capacitor
across the input of the converter will ensure stable operation.
The capacitor is not required when powering the DC/DC
converter from an input source with an inductance below
10 μH.
External Decoupling Capacitors
When powering loads with significant dynamic current
requirements, the voltage regulation at the point of load can
be improved by addition of decouplin
g
capacitors at the load.
The most effective technique is to locate low ESR ceramic
and electrolytic capacitors as close to the load as possible,
using several parallel capacitors to lower the effective ESR.
The ceramic capacitors will handle high-frequency dynamic
load changes while the electrolytic capacitors are used to
handle low frequency dynamic load changes. Ceramic
capacitors will also reduce any high frequency noise at the
load.
It is equally important to use low resistance and low
inductance PCB layouts and cabling.
External decoupling capacitors will become part of the
control loop of the DC/DC converter and may affect the
stability margins. As a “rule of thumb”, 100 μF/A of output
current can be added without any additional analysis. The
ESR of the capacitors is a very important parameter. Power
Modules guarantee stable operation with a verified ESR value
of >10 mΩ across the output connections.
For further information please contact your local Ericsson
Power Modules representative.
Output Voltage Adjust (Vadj)
The DC/DC converters have an Output Voltage Adjust pin
(Vadj). This pin can be used to adjust the output voltage above
or below Output voltage initial setting.
When increasing the output voltage, the voltage at the output
pins (including any remote sense compensation ) must be
kept below the threshold of the over volta
g
e protection, (OVP)
to prevent the converter from shutting down. At increased
output voltages the maximum power rating of the converter
remains the same, and the max output current must be
decreased correspondingly.
To increase the voltage the resistor should be connected
between the Vadj pin and +Sense pin. The resistor value of the
Output voltage adjust function is according to information
given under the Output section for the respective product.
To decrease the output voltage, the resistor should be
connected between the Vadj pin and —Sense pin.
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
9
Ericsson Internal
PRODUCT SPECIFICATION 3 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 3/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (Julia You) ECHWANG 2007-6-18 A
Operating information continued
Remote Sense
The DC/DC converters have remote sense that can be used
to compensate for voltage drops between the output and the
point of load. The sense traces should be located close to the
PCB ground layer to reduce noise susceptibility. The remote
sense circuitry will compensate for up to 10% voltage drop
between output pins and the point of load.
If the remote sense is not needed +Sense should be
connected to +Out and -Sense should be connected to -Out.
Over Temperature Protection (OTP)
The converters are protected from thermal overload by an
internal over temperature shutdown function of the control IC.
When Tref as defined in thermal consideration section
exceeds 120°C the converter will shut down. The DC/DC
converter will make continuous attempts to start up (non-
latching mode) and resume normal operation automatically
when the temperature has dropped >10°C below the
temperature threshold.
Over Voltage Protection (OVP)
The converters have output over voltage protection that will
shut down the converter in over voltage conditions. The
converter will make continuous attempts to start up (non-
latching mode) and resume normal operation automatically
after removal of the over voltage condition.
Over Current Protection (OCP)
The converters include current limiting circuitry for protection
at continuous overload.
The output voltage will decrease towards zero for output
currents in excess of max output current (max IO). The
converter will resume normal operation after removal of the
overload. The load distribution should be designed for the
maximum output short circuit current specified.
Thermal Consideration
General
The converters 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 converter. Increased airflow enhances the
cooling of the converter.
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 = 53 V.
The DC/DC converter is tested on a 254 x 254 mm,
35 μm (1 oz), 16-layer test board mounted vertically in a wind
tunnel with a cross-section of 305 x 305 mm.
Proper cooling of the DC/DC converter 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 +90°C.
See Design Note 019 for further information.
Position Device Designation max value
P1 Pcb
Tref 110º C
P2 Mosfet
Tref 120º C
P3 Mosfet
Tref 120º C
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
10
Ericsson Internal
PRODUCT SPECIFICATION 4 (5)
Prepared (also subject responsible if other) No.
EJUNGYA 3/1301-BMR 636 01/A4 Uen
Approved Checked Date Rev Reference
SEC/D (Julia You) ECHWANG 2007-6-18 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
By using the thermal resistance the maximum allowed
ambient temperature can be calculated.
1. The power loss is calculated by using the formula
((1/η) - 1) × output power = power losses (Pd).
η = efficiency of converter. E.g 89.5 % = 0.895
2. Find the thermal resistance (Rth) in the Thermal Resistance
graph found in the Output section for each model.
Calculate the temperature increase (ΔT).
ΔT = Rth x Pd
3. Max allowed ambient temperature is:
Max Tref - ΔT.
E.g PKB 4717 PINB at 1m/s with full load:
1. (( ) - 1) × 75 W = 8.79 W
2. 8.79 W × 6.0°C/W = 53°C
3. 110 °C - 53°C = max ambient temperature is 57°C
The actual temperature will be dependent on several factors
such as the PCB size, number of layers and direction of
airflow.
Connections
Pin Designation Function
1 +In Positive input
2 RC Remote control
3 -In Negative input
4 -Out Negative output
5 -Sen Negative remote sense
6 Vadj Output voltage adjust
7 +Sen Positive remote sense
8 +Out Positive output
1
0.895
E
PKB 4717 PINB
DC/DC converters, Input 36-75 V, Output 10.5 A/75 W
EN/LZT 146 382 R1A June 2007
© Ericsson Power Modules AB
Technical Specification
11