Ericsson Internal
E
SECSUND
PRODUCT SPECIFICATION
3 (7)
Prepared (also subject responsible if other)
No.
30/1301-BMR 451 0002 Uen
14
Technical Specification
Approved
Checked
Date
Rev
Reference
EN/LZT 146 401 R4A May 2015
BMR 451 Digital PoL Regulators
Input 4.5-14 V, Output up to 40 A / 132 W
2015-05-15
PJ1
© Ericsson AB
The following table shows recommended resistor values for
RSET.
others on the same synchronization bus should be configured
with SYNC Input or SYNC Auto Detect (Default configuration)
for correct operation. When the FLEX pin is configured in auto
detect mode the product will automatically check for a clock
signal on the FLEX pin. The switching frequency can also be
set to any value between 200 kHz and 400 kHz using the
PMBus interface. Please contact your local Ericsson Power
Modules representative for design support of custom
configurations or appropriate SW tools for design and down-
load of new configurations.
Rset[kΩ]
Rset[kΩ]
Max VOUT [V] Min Typ Max
VOUT
[V]
Min
Typ
0.7 155.00 159.00 169.00 0.991 21.38 21.60 21.82
0.752 109.89 111.00 112.11
0.758 99.00 100.00 101.00
0.765 89.10 90.00 90.90
0.772 80.09 80.90 81.71
0.79 64.35 72.50 73.23
0.80 57.52 58.10 58.68
0.821 51.38 51.90 52.42
0.848 40.69 41.10 41.51
0.88 36.04 36.40 36.76
0.899 31.88 32.20 32.52
0.919 28.02 28.30 28.58
0.965 24.55 24.80 25.05
1.00 18.51 18.70 18.89
1.10 15.94 16.10 16.26
1.158 13.56 13.70 13.84
1.20 11.39 11.50 11.62
1.25 9.50 9.60 9.70
1.50 7.72 7.80 7.88
1.669 6.14 6.20 6.26
1.80 4.65 4.70 4.75
2.295 3.27 3.30 3.33
2.506 2.08 2.10 2.12
3.30 0.99 1.00 1.01
Interleaving
When multiple DC/DC regulators share a common DC input
supply, interleaving, or spreading of the switching clock phase
between the regulators can be utilized. This dramatically
reduces input capacitance requirements and efficiency losses,
since the peak current drawn from the input supply is
effectively spread out over the whole switch period. This
requires that the DC/DC regulators are synchronized. Up to 16
different interleaving phases can be used. The interleaving of
the product can be reconfigured using the PMBus interface.
Please contact your local Ericsson Power Modules
representative for design support of custom configurations or
appropriate SW tools for design and down-load of new
configurations.
Output Voltage Adjust using PMBus
Parallel Operation
The output voltage of the product can be reconfigured using
the PMBus interface in the range 0.6 V to 3.6 V with the
resolution of 1 mV. Please contact your local Ericsson Power
Modules representative for design support of custom
configurations or appropriate SW tools for design and down-
load of new configurations.
Parallel operation is not recommended.
Over Temperature Protection (OTP)
The products are protected from thermal overload by an
internal over temperature shutdown circuit.
When TP1 as defined in thermal consideration section exceeds
120°C the product will shut down. The product will make
continuous attempts to start up (non-latching mode) and
resume normal operation automatically when the temperature
has dropped >15°C below the temperature threshold. Please
contact your local Ericsson Power Modules representative for
design support of custom configurations or appropriate SW
tools for design and down-load of new configurations.
Maximum Output Voltage Protection
The regulator can be configured for maximum output voltage
protection. The Analog Voltage Adjust sets the maximum
output voltage equal to 10% higher than the nominal output
value set by the RSET. This works as a hardware protection for
the load, avoiding destroying the load by an over voltage.
Please contact your local Ericsson Power Modules
representative for design support of custom configurations or
appropriate SW tools for design and down-load of new
configurations.
Over Current Protection (OCP)
The product includes current limiting circuitry for protection at
continuous overload. The product will shut down immediately
for output currents in excess of the current limit, Ilim. The
product will try to restart every 70 ms, i.e., hiccup mode, and
resume normal operation after removal of the overload. The
load distribution should be designed for the maximum output
short circuit current specified Please contact your local
Ericsson Power Modules representative for design support of
custom configurations or appropriate SW tools for design and
down-load of new configurations.
Synchronization
Synchronization is a feature that allows multiple DC/DC
regulators to be synchronized to a common frequency.
Synchronized regulators powered from the same bus eliminate
beat frequencies reflected back to the input supply, and also
reduces EMI filtering requirements. Eliminating the slow beat
frequencies (usually < 10 kHz) allows the EMI filter to be
designed to attenuate only the synchronization frequency.
Synchronization can also be utilized for interleaving, described
in section Interleaving. The product FLEX pin can be
configured for synchronization. Hence, Analog Voltage Adjust
is disabled, when the synchronization is enabled. The
regulators can be synchronized with an external oscillator or
one regulator can be configured with the FLEX pin as an SYNC
Output working as a master driving the synchronization. All
Soft-start Power Up
The soft-start control introduces a time-delay (default setting 10
ms) before allowing the output voltage to rise. The default rise
time of the ramp up is 10 ms. Power-up is hence completed
within 20 ms in default configuration using remote control.
ERICSSON [ ERICSSON ]
