LM34914EVAL National Semiconductor, LM34914EVAL Datasheet - Page 2

• Manufacturer Part Number: LM34914EVAL
• Description: BOARD EVALUATION LM34914
• Manufacturer: National Semiconductor

Specifications of LM34914EVAL

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 5V
• Current - Output: 1A
• Voltage - Input: 8 ~ 40V
• Regulator Topology: Buck
• Frequency - Switching: 275kHz
• Board Type: Fully Populated
• Utilized Ic / Part: LM34914
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Power - Output: -

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Pin Number
Connection Diagram
Ordering Information
Pin Descriptions
Order Number
LM34914 SDX
LM34914 SD
10
1
2
3
4
5
6
7
8
9
RON/SD
SGND
Name
ISEN
RTN
BST
Package Type
V
VIN
SW
FB
SS
EP
LLP-10 (3x3)
LLP-10 (3x3)
CC
Switching Node
Boost pin for bootstrap capacitor
Current sense
Sense Ground
Circuit Ground
Feedback input from the regulated
output
Softstart
On-time control and shutdown
Output from the startup regulator
Input supply voltage
Exposed Pad
NSC Package
Drawing
SDA10A
SDA10A
Description
10-Lead LLP
Junction Temperature Range
2
−40°C to + 125°C
−40°C to + 125°C
Internally connected to the buck switch source. Connect to
the inductor, diode, and bootstrap capacitor.
Connect a 0.022 µF capacitor from SW to this pin. The
capacitor is charged each off-time via an internal diode.
The re-circulating current flows out of this pin to the free-
wheeling diode.
Re-circulating current flows into this pin to the current sense
resistor.
Ground for all internal circuitry other than the current limit
detection.
Internally connected to the regulation and over-voltage
comparators. The regulation level is 2.5V.
An internal current source charges an external capacitor to
2.5V, providing the softstart function.
An external resistor from VIN to this pin sets the buck switch
on-time. Grounding this pin shuts down the regulator.
Nominally regulated at 7.0V. Connect a 0.1 µF capacitor
from this pin to RTN. An external voltage (8V to 14V) can be
applied to this pin to reduce internal dissipation. An internal
diode connects VCC to VIN.
Operating input range is 8.0V to 40V.
Exposed metal pad on the underside of the device. It is
recommended to connect this pad to the PC board ground
plane to aid in heat dissipation.
20197302
Application Information
1000 Units on Tape and Reel
3500 Units on Tape and Reel
Supplied As