OKDY-T Datasheet, PDF (22/41 Pages) Murata Power Solutions Inc. – 50A Digital PoL DC-DC Converter Series

OKDx-T/50-W12-C
50A Digital PoL DC-DC Converter Series
A = 3289.56,
B = -6248.12,
C = 2964.06
Write 0x7CB941FDC3417CCD99 to PID_TAPS register and write
command STORE_USER_ALL
Note that if DLC is enabled, for best results VI must be stable before
DLC algorithm begins.
Load Transient Response Optimization
The product incorporates a Non-Linear transient Response, NLR, loop
that decreases the response time and the output voltage deviation
during a load transient. The NLR results in a higher equivalent loop
bandwidth than is possible using a traditional linear control loop. The
product is pre-configured with appropriate NLR settings for robust and
stable operation for a wide range of input voltage and a capacitive
load range as defined in the section External Decoupling Capacitors.
For an application with a specific input voltage, output voltage, and
capacitive load, the NLR configuration can be optimized for a robust
and stable operation and with an improved load transient response.
This will also reduce the amount of output decoupling capacitors and
yield a reduced cost. However, the NLR slightly reduces the effi-
ciency. In order to obtain maximal energy efficiency the load transient
requirement has to be met by the standard control loop compensation
and the decoupling capacitors. The NLR settings can be reconfigured
using the PMBus interface.
Remote Sense
The product has 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 PWB ground layer to reduce
noise susceptibility. Due to derating of internal output capacitance
the voltage drop should be kept below V_DROPMAX = (5.5–V_O)/2. A large
voltage drop will impact the electrical performance of the regulator. If
the remote sense is not needed, +S should be connected to VOUT and
−S should be connected to GND.
Output Voltage Adjust using Pin-strap Resistor
Using an external Pin-strap resis-
tor, RSET, the output voltage can
VSET
be set in the range 0.6 V to 3.3
R _SET
PREF
V at 28 different levels shown
in the table below. The resistor
should be applied between the
VSET pin and the PREF pin.
RSET also sets the maximum output voltage, see section “Output
Voltage Range Limitation.” The resistor is sensed only during product
start-up. Changing the resistor value during normal operation will
not change the output voltage. The input voltage must be at least 1
V larger than the output voltage in order to deliver the correct output
voltage. See Ordering Information for output voltage range.
The following table shows recommended resistor values for RSET.
Maximum 1% tolerance resistors are required.
www.murata-ps.com/support
V_O [V]
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
1.05
1.10
1.15
1.20
1.25
1.30
1.40
R_SET[kΩ]
10
11
12.1
13.3
14.7
16.2
17.8
19.6
21.5
23.7
26.1
28.7
31.6
34.8
38.3
42.2
V_O [V]
1.50
1.60
1.70
1.80
1.90
2.00
2.10
2.20
2.30
2.50
3.00
3.30
R_SET[kΩ]
46.4
51.1
56.2
61.9
68.1
75
82.5
90.9
100
110
121
133
The output voltage and the maximum output voltage can be pin
strapped to three fixed values by connecting the VSET pin according
to the table below.
V_O [V]
0.60
1.2
2.5
VSET
Shorted to PREF
Open “high impedance”
Logic High, GND as reference
Output Voltage Adjust using PMBus
The output voltage set by pin-strap can be overridden by configuration
file or by using a PMBus command. See Electrical Specification for
adjustment range.
When setting the output voltage by configuration file or by a PMBus
command, the specified output voltage accuracy is valid only when
the set output voltage level falls within the same bin range as the
voltage level defined by the pin-strap resistor RSET. The applicable bin
ranges are defined in the table below. Valid accuracy for voltage levels
outside the applicable bin range is two times the specified.
Example:
Nominal VO is set to 1.10 V by RSET = 26.1 kΩ. 1.10 V falls within the
bin range 0.988-1.383 V, thus specified accuracy is valid when adjust-
ing VO within 0.988-1.383V.
V_O bin ranges [V]
0.600 – 0.988
0.988 – 1.383
1.383 – 1.975
1.975 – 2.398
2.398 – 2.963
2.963 – 3.753
Output Voltage Range Limitation
The output voltage range that is possible to set by configuration or
by the PMBus interface is limited by the pin-strap resistor RSET. The
maximum output voltage is set to 110% of the nominal output value
defined by RSET, V_O,MAX = 1.1 x V_O,RSET. This protects the load from an
over voltage due to an accidental wrong PMBus command.
MDC_OKDx-T/50-W12-C.A04 Page 22 of 41