Features
• Wide-Input Voltage Range:
18 V to 60 V
• 20 A Total Output Current
• 90% Efficiency
• Wide-Adjust Output Voltage:
1.8 V to 3.6 V
• Over-Current Protection
• Output Over-Voltage Protection
• Over-Temperature Shutdown
• Output Enable Control
• Auto-Track Compatible
Sequenced Output
• Smart-Sense Remote Sensing
• Under-voltage Lockout
• Industry Standard Footprint
• Surface Mountable
• 1500 VDC Isolation
• Agency Approvals (Pending):
UL/cUL 60950, EN 60950

Description
The PTB78520W is a 20-A rated,
wide-input (18-60 V) isolated DC/DC
converter that incorporates Auto-Track™
power-up sequencing. This allows these
modules to simultaneously power up with
any other downstream non-isolated, Auto-
Track compliant module.
The PTB78520W module provides
two outputs, each regulated to the same
voltage. During power up, the voltage at
‘VO Bus’ rises first, allowing this output
to provide input power to any downstream
non-isolated module. The voltage from
‘VO Seq’ is then allowed to rise simultaneously,
under the control of Auto-Track,
along with the outputs from the downstream
modules.
Whether used to facilitate power-up
sequencing, or operated as a stand-alone
module, the PTB78520W includes many
features expected of high-performance
DC/DC converter modules. The combi-
nation of input-output isolation and a
wide-input voltage range, allows operation
from either +24 V or –48 V. The wideoutput
adjust enables the output voltage
to be set to to any voltage over the range,
1.8 V to 3.6 V, using a single external
resistor. Precise output voltage regulation
is assured using Smart-Sense. This
is a differential remote sense that will
intelligently regulate the sequenced output,
depending on its sequence status.
Other operational features include an
input under-voltage lockout (UVLO) and
an output enable control. Over-current,
over-voltage, and over-temperature protection
assures the module’s ability to
survive any load fault.
Typical applications include distributed
power architectures in both telecom and
computing environments, particularly
complex digital systems requiring powersequencing
of multiple power supply rails.