LM34910C - High Voltage (50V, 1.25A) Step Down Switching Regulator

Datasheet	Packaging	Samples & Pricing	Reliability	Design Tools	Application Notes	Knowledge Base

Features

•	Integrated 55V, N-Channel buck switch
•	Integrated start-up regulator
•	Input Voltage Range: 8V to 50V
•	No loop compensation required
•	Ultra-Fast transient response
•	Operating frequency remains constant with load current and input voltage
•	Maximum Duty Cycle Limited During Start-Up
•	Adjustable output voltage
•	Valley Current Limit At 1.25A
•	Precision internal reference
•	Low bias current
•	Highly efficient operation
•	Thermal shutdown

General Description

The LM34910C Step Down Switching Regulator features all of the functions needed to implement a low cost, efficient, buck bias regulator capable of supplying 1.25A to the load. More...

Typical Application

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Parameters Values

Output Current 1250 mA

Input Min Voltage 8 Volt

Input Max Voltage 50 Volt

Output Min 2.5 Volt

Output Max 45 Volt

Frequency Min Undefined kHz

Frequency Max 1000 kHz

Efficiency (peak) 92 %

On/Off Pin Yes

Error Flag No

SoftStart Yes

Sync Pin No

Inverting Yes

Flyback No

RegType Switching Regulator

Temperature Min -40 deg C

Temperature Max 125 deg C

Adjustable Output Yes

Adj Switch Frequency Yes

PWM Mode Constant on-time

Topology Buck

Special Features No compensation req'rd; ultra fast transient response

Step-Down Yes

Multiple Output Capability No

Output Power Undefined Watt

Output Voltage Undefined Volt

Output Range 2.5V to 45V

Switching Frequency 1000 kHz

Feedback Voltage 2.5 Volt

Regulator Family Undefined

Automotive Yes

Synchronous Rectification No

WEBENCH Live Simulation!

LM34910C
8.00 <=	V in Lower V	<=	V in Upper V	<= 50.00
V out	2.50 <=		V	<= 47.00
I out			A	<= 1.00
Ambient Temperature			°C	<= 100
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Additional Resources

Design Tools

Application Notes

Connection Diagram

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Datasheet

RoHS Compliance Information	Size in Kbytes	Date
LM34910C High Voltage (50V, 1.25A) Step Down Switching Regulator	271 Kbytes	24-Aug-07	Download

If you have trouble printing or viewing PDF file(s), see Printing Problems.

Package Availability, Models, Samples & Pricing

Part Number

Package

Factory Lead Time

Models

Samples &
Electronic
Orders

Budgetary Pricing

Std
Pack
Size

Package
Marking
Format

Type

Pins

Spec.

MSL
Rating

Peak
Reflow

RoHS
Report

CAD
Symbols

Weeks

Qty

$US each

LM34910CSDE

LLP

NOPB

260

RoHS

Download

Full production

N/A

1K+

$1.35

reel
of
250

NS
UZXYTT
L34910C

6 weeks

N/A

LM34910CSD

LLP

NOPB

260

RoHS

Download

Full production

N/A

1K+

$1.35

reel
of
1000

NS
UZXYTT
L34910C

6 weeks

N/A

LM34910CSDX

LLP

NOPB

260

RoHS

Download

Full production

N/A

1K+

$1.35

reel
of
4500

NS
UZXYTT
L34910C

6 weeks

N/A

General Description

The LM34910C Step Down Switching Regulator features all of the functions needed to implement a low cost, efficient, buck bias regulator capable of supplying 1.25A to the load. This buck regulator contains a 55V N-Channel Buck Switch, and is available in the thermally enhanced LLP-10 package. The hysteretic regulation scheme requires no loop compensation, results in fast load transient response, and simplifies circuit implementation. The operating frequency remains constant with line and load variations due to the inverse relationship between the input voltage and the on-time. The current limit detection is set at 1.25A. Additional features include: VCC under-voltage lockout, thermal shutdown, gate drive under-voltage lockout, and maximum duty cycle limiter.

Reliability Metrics

Part Number	Process	EFR Sample Size	LTA Device Hours	FITS	MTTF (Hours)
LM34910CSD	ABCD150XV1	3868	2595000	2	736338335
LM34910CSDE	ABCD150XV1	3868	2595000	2	736338335
LM34910CSDX	ABCD150XV1	3868	2595000	2	736338335

Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

For more information on Reliability Metrics, please click here.

Design Tools

Title	Size in Kbytes	Date
LM34910C Quick Start Calculator	365 Kbytes	28-Jul-2009	View

If you have trouble printing or viewing PDF file(s), see Printing Problems.

More Application Notes

Title	Size in Kbytes	Date
AN-1349: Application Note 1349 LM34910 Evaluation Board	562 Kbytes	18-Nov-04	Download

If you have trouble printing or viewing PDF file(s), see Printing Problems.

[Information as of 8-Nov-2009]