LMZ23610 Datasheet, PDF (1/16 Pages) National Semiconductor (TI) – Sharing Evaluation Board power modules are easy-to-use DC-DC

LMZ23610/8/6 and
LMZ22010/8/6 Current
Sharing Evaluation Board
National Semiconductor
Application Note 2093
Marc Davis-Marsh
April 7, 2010
Introduction
The LMZ23610/8/6 and LMZ22010/8/6 SIMPLE SWITCH-
ER® power modules are easy-to-use DC-DC solution capa-
ble of driving up to a 10, 8 or 6 ampere load. They are
available in an innovative package that enhances thermal
performance and allows for hand or machine soldering. The
LMZ23610/8/6 can accept an input voltage rail between 6V
and 36V and the LMZ22010/8/6 can accept an input voltage
rail between 6V and 20V.
The current sharing evaluation board is designed so that four
modules can be easily connected to supply up to a 40 amp
load. More can be connected as long as care is taken to not
exceed the current capabilities of the banana plug connectors
and the 5-amp per pin rating of the edge board connector.
The current sharing evaluation board is highly configurable.
The output voltage can be changed to 5V, 3.3V, 2.5V or 1.2V
with a jumper change. The external soft-start capacitor facil-
itates a controlled and adjustable startup rise time of the
output. The board temperature can be measured with the on-
board resistor. The UVLO can be adjusted by adding one
resistor. To simplify the synchronization of the modules an
onboard 555 timer provides an adjustable frequency clock
from 350 to 600 kHz.
The LMZ23610 and LMZ22010 family is a reliable and robust
solution with the following features: loss-less cycle-by-cycle
valley current limit to protect for over current or short-circuit
fault, thermal shutdown, input under-voltage lockout, and will
start up into a pre-biased output.
Board Specifications
• V_IN = 6V to 36V (LMZ23610/8/6)
• V_IN = 6V to 20V (LMZ22010/8/6)
• V_OUT = 1.2V, 2.5V, 3.3V or 5V (minimum input voltage of
7V required for 5V output)
• I_OUT = 0 to 10, 8, or 6 Amps
• θ_JA = 8.8 °C / W, θ_JC = 1.0 °C/W
• Designed on four layers; Inner are 2 oz copper; Outer are
2 oz copper.
• Measures 3.54" x 3.54" (90 mm x 90 mm) and is 62 mils
(1.57 mm) thick of FR4 laminate material
For additional circuit considerations, including additional out-
put voltage options, refer to the Applications Section section
of the LMZ23610/8/6 or LMZ22010/8/6 data sheets. For neg-
ative output voltage connections see AN-2027.
Simplified Schematic
© 2011 National Semiconductor Corporation 301387
FIGURE 1.
30138708
www.national.com