LM34923EVAL/NOPB National Semiconductor, LM34923EVAL/NOPB Datasheet - Page 2

• Manufacturer Part Number: LM34923EVAL/NOPB
• Description: BOARD EVALUATION FOR LM34923
• Manufacturer: National Semiconductor
• Series: -r

Specifications of LM34923EVAL/NOPB

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Power - Output: -
• Voltage - Output: 5V
• Current - Output: 500mA
• Voltage - Input: 6 ~ 75 V
• Regulator Topology: Buck
• Frequency - Switching: 200kHz
• Board Type: Fully Populated
• Utilized Ic / Part: LM34923
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

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Pin
10
1
2
3
4
5
6
7
8
9
Connection Diagram
Ordering Information
Pin Descriptions
RT/SD
Name
UVO
RTN
VCC
BST
N/C
SW
VIN
UV
FB
Order Number
LM34923MMX
LM34923MM
Switching Node
Boost Pin
Do not connect
Ground pin
Input pin for the under voltage
indicator
Under voltage status indicator
Feedback Input from Regulated
Output
On-time set pin and shutdown input
Output from the internal high voltage
series pass regulator. Regulated at
7.5V.
Input Voltage
Description
Package Type
MSOP-10
Power switching node. Connect to the output inductor, re-circulating diode or
synchronous FET, and bootstrap capacitor.
An external capacitor is required between the BST and the SW pins (0.01uF
or greater ceramic). The BST pin capacitor is charged from Vcc through an
internal diode when SW is low.
Ground for the entire circuit.
A resistor divider from VIN, or some other system voltage, programs the under-
voltage detection threshold. An internal current sink is enabled when UV is
below 2.5V to provide hysteresis.
This open drain output is high when the UV pin voltage is below 2.5V, or when
the VCC
This pin is connected to the inverting input of the internal regulation
comparator. The regulation level is 2.5V.
A resistor between this pin and Vin sets the switch on-time as a function of Vin,
and the frequency. The minimum recommended on-time is 200 ns at max input
voltage. Taking this pin to ground shuts off the regulator.
The internal regulator provides bias supply for the Buck switch gate driver and
other internal circuitry. A 1uF ceramic capacitor to ground is required. The
regulator is current limited to
The operating input range is 6V to 75V
10–Lead MSOP
Top View
UVLO
2
function or the shutdown function is invoked.
NSC Package Drawing
MUB10A
Application Information
≈
30 mA.
30141702
1000 Units on Tape and Reel
3500 Units on Tape and Reel
Supplied As