LM5026EVAL National Semiconductor, LM5026EVAL Datasheet - Page 2

• Manufacturer Part Number: LM5026EVAL
• Description: BOARD EVALUATION LM5026
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM5026EVAL

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Isolated
• Voltage - Output: 3.3V
• Current - Output: 30A
• Voltage - Input: 36 ~ 78V
• Regulator Topology: Buck
• Frequency - Switching: 230kHz
• Board Type: Fully Populated
• Utilized Ic / Part: LM5026
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• Power - Output: -

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Order Number
LM5026MT
LM5026MTX
LM5026SD
LM5026SDX
Connection Diagrams
Ordering Information
Pin Descriptions
Pin
1
2
3
4
5
6
7
8
OUT_A
Name
UVLO
TIME
RES
REF
VCC
VIN
CS
16-Lead TSSOP
Input Voltage Source
Line Under-Voltage Lockout An external voltage divider from the power source sets the shutdown and
Current Sense input for
current mode control and
current limit
Restart Timer
Gate Drive Overlap or
Deadtime Control
Output of 5V Reference
Output of the high voltage
start-up regulator. The VCC
voltage is regulated to 7.6 V.
Main Output Driver
Package Type
TSSOP-16
TSSOP-16
LLP-16
LLP-16
Description
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Input to the Start-up Regulator. Operating input range is 13V to 100V with
transient capability to 105V. For power sources outside of this range, the
LM5026 can be biased directly at VCC by an external regulator.
standby comparator levels. When UVLO reaches the 0.4V threshold the
VCC and REF regulators are enabled. At the 1.25V threshold the SS pin is
released and the device enters the active mode.
If CS exceeds 0.5V the output pulse will be terminated, entering cycle-by-
cycle current limit. An internal switch holds CS low for 100nS after OUT_A
switches high to blank leading edge transients.
If cycle-by-cycle current limit is reached during any cycle, a 10uA current
is sourced to the RES pin capacitor. If the RES capacitor voltage reaches
2.5V, the soft-start capacitor will be fully discharged and then released with
a pull-up current of 1uA. After the first output pulse at OUT_A (when SS
=1.4V), the SS pin charging current will revert back to 50 µA.
An external resistor (RSET) sets either the overlap time or deadtime for the
active clamp output. An RSET resistor connected between TIME and
AGND produces in-phase OUT_A and OUT_B pulses with overlap. An
RSET resistor connected between TIME and REF produces out-of-phase
OUT_A and OUT_B pulses with deadtime.
Maximum output current is 10mA. Locally decouple with a 0.1µF capacitor.
If an auxiliary winding raises the voltage on this pin above the regulation
setpoint, the internal start-up regulator will shutdown, thus reducing the IC
power dissipation.
Output of the main switch PWM gate driver. Capable of 3A peak sink
current.
2
NSC Package Drawing
MTC16
MTC16
SDA16A
SDA16A
Application Information
16-Lead LLP
Supplied As
92 Units per anti-static tube
2500 Units on Tape and Reel
1000 Units on Tape and Reel
4500 Units on Tape and Reel
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