UDT020A0X3-SRZ Lineage Power, UDT020A0X3-SRZ Datasheet - Page 19

• Manufacturer Part Number: UDT020A0X3-SRZ
• Description: DC/DC Converters & Regulators 3-14.4Vin .6-5.5Vout 20A Neg SMT Digital
• Manufacturer: Lineage Power

Specifications of UDT020A0X3-SRZ

• Product: Non-Isolated / POL
• Input Voltage Range: 3 VDC to 14.4 VDC
• Input Voltage (nominal): 12 V
• Output Voltage (channel 1): 0.6 VDC to 5.5 VDC
• Output Current (channel 1): 20 A
• Output Voltage: 0.6 VDC to 5.5 VDC
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Preliminary Data Sheet
May 10, 2011
Digital Feature Descriptions
PMBus Interface Capability
The 20A Digital Micro DLynx
PMBus interface that supports both communication
and control. The PMBus Power Management Protocol
Specification can be obtained from
The modules support a subset of version 1.1 of the
specification (see Table 6 for a list of the specific
commands supported). Most module parameters can
be programmed using PMBus and stored as defaults
for later use.
All communication over the module PMBus interface
must support the Packet Error Checking (PEC)
scheme. The PMBus master must generate the correct
PEC byte for all transactions, and check the PEC byte
returned by the module.
The module also supports the SMBALERT response
protocol whereby the module can alert the bus master
if it wants to talk. For more information on the SMBus
alert response protocol, see the System Management
Bus (SMBus) specification.
The module has non-volatile memory that is used to
store configuration settings. Not all settings
programmed into the device are automatically saved
into this non-volatile memory, only those specifically
identified as capable of being stored can be saved
(see Table 6 for which command parameters can be
saved to non-volatile storage).
PMBus Data Format
For commands that set thresholds, voltages or report
such quantities, the module supports the “Linear” data
format among the three data formats supported by
PMBus. The Linear Data Format is a two byte value
with an 11-bit, two’s complement mantissa and a 5-bit,
two’s complement exponent. The format of the two
data bytes is shown below:
The value is of the number is then given by
PMBus Addressing
The power module can be addressed through the
PMBus using a device address. The module has 64
possible addresses (0 to 63 in decimal) which can be
set using resistors connected from the ADDR0 and
ADDR1 pins to GND. Note that some of these
addresses (0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 40 in decimal)
are reserved according to the SMBus specifications
and may not be useable. The address is set in the
form of two octal (0 to 7) digits, with each pin setting
LINEAGE
MSB
7 6 5 4 3
Exponent
Data Byte High
POWER
Value = Mantissa x 2
MSB
2 1 0 7 6 5 4 3 2 1 0
TM
Mantissa
power modules have a
Data Byte Low
3 – 14.4Vdc input; 0.45Vdc to 5.5Vdc output; 20A output current
20A Digital Micro DLynx
www.pmbus.org.
Exponent
one digit. The ADDR1 pin sets the high order digit and
ADDR0 sets the low order digit. The resistor values
suggested for each digit are shown in Table 4 (1%
tolerance resistors are recommended). Note that if
either address resistor value is outside the range
specified in Table 4, the module will respond to
address 127.
The user must know which I
in a system for special functions and set the address of
the module to avoid interfering with other system
operations. Both 100kHz and 400kHz bus speeds are
supported by the module. Connection for the PMBus
interface should follow the High Power DC
specifications given in section 3.1.3 in the SMBus
specification V2.0 for the 400kHz bus speed or the
Low Power DC specifications in section 3.1.2. The
complete SMBus specification is available from the
SMBus web site, smbus.org.
Figure 47. Circuit showing connection of resistors
used to set the PMBus address of the module.
PMBus Enabled On/Off
The module can also be turned on and off via the
PMBus interface. The OPERATION command is used
to actually turn the module on and off via the PMBus,
while the ON_OFF_CONFIG command configures the
combination of analog ON/OFF pin input and PMBus
commands needed to turn the module on and off. Bit
[7] in the OPERATION command data byte enables
the module, with the following functions:
This module uses the lower five bits of the
ON_OFF_CONFIG data byte to set various ON/OFF
options as follows:
TM
: Non-isolated DC-DC Power Modules
0
1
:
:
Digit
Output is disabled
Output is enabled
0
1
2
3
4
5
6
7
SIG_GND
ADDR1
ADDR0
Resistor Value (KΩ)
Table 4
2
C addresses are reserved
15.4
23.7
36.5
54.9
84.5
130
200
10
R
ADDR0
R
ADDR1
19