PTEA420025 Datasheet, PDF (5/16 Pages) Texas Instruments – 20-A, 48-V INPUT, ISOLATED, 1/8th BRICK DC-DC CONVERTER

PTEA420025, PTEA420033
www.ti.com
SLTS288C – JUNE 2007 – REVISED OCTOBER 2010
PIN DESCRIPTIONS
+V_I: The positive input for the module with respect to –V_I. When powering the module from a –48-V telecom
central office supply, this input is connected to the primary system ground.
–V_I: The negative input supply for the module, and the 0 VDC reference for the Remote On/Off input. When
powering the module from a +48-V supply, this input is connected to the 48-V return.
Remote On/Off: This input controls the On/Off status of the output voltage. It is either driven low (–V_I potential),
or left open-circuit. For units identified with the NEN option, applying a logic low to this pin will enable the output.
And for units identified with the PEN option, the output will be disabled.
V_O Adjust: Allows the output voltage to be trimmed by up or down between +10% and –20% of its nominal
value. The adjustment method uses a single external resistor. Connecting the resistor between V_O Adjust and
–V_O adjusts the output voltage lower, and placing it between V_O Adjust and +V_O adjusts the output higher. The
calculations for the resistance value follows industry standard formulas. For further information consult the
application note on output voltage adustment.
+V_O: The positive power output with respect to –V_O, which is DC isolated from the input supply pins. If a negative
output voltage is desired, +V_O should be connected to the secondary circuit common and the output taken from
–V_O.
–V_O: The negative power output with respect to +V_O, which is DC isolated from the input supply pins. This output
is normally connected to the secondary circuit common when a positive output voltage is desired.
Sense(+): Provides the converter with an output sense capability to regulate the set-point voltage directly at the
load. When used with Sense(-), the regulation circuitry will compensate for voltage drop between the converter
and the load. The pin may be left open circuit, but connecting it to +V_O will improve load regulation.
Sense(–): Provides the converter with an output sense capability when used in conjunction with Sense(+) input.
For optimum output voltage accuracy this pin should always be connected to –V_O.
PTEA4200xx
(Top View)
1
+V_I
2
On/Off
3
−V_I
+V_O
8
Sense(+)
7
Adjust
6
5
Sense(−)
−V_O
4
Copyright © 2007–2010, Texas Instruments Incorporated
Submit Documentation Feedback
5
Product Folder Link(s): PTEA420025 PTEA420033