LT3905

PRODUCTION

LT3905

Boost DC/DC Converter with APD Current Monitor

PRODUCTION

Not the part you were looking for?

Go to Product Selection Table

View All Documentation

Ask a Question

Submit your question below and we will return the best answer from ADI’s knowledge database:

Other places you can find help

Support

Analog Devices Support Portal is a one-stop shop to answer all your ADI questions.

Visit the ADI Support Page

Ask the ADI community for help.

Ask the EngineerZone Community

FAQs

Sales & Ordering FAQs

Part Models 4

1ku List Price Starting From $3.07

Features

65V, 350mA Internal DMOS Switch
Integrated Schottky Diode
2% Accurate APD Current Monitoring Over the 3μA to 3mA Range
Single Resistor Programs Maximum APD Current
Fast APD Current Limiter with Indicator
Programmable Loss-of-Signal Indicator
CTRL Pin Adjusts Output Voltage
Programmable V_IN Undervoltage Lockout
High Efficiency Step-Up Converter
Selectable 1MHz/2MHz Switching Frequency
Internally Compensated
Internal Soft-Start
2.7V to 12V V_IN Range
Low Shutdown Current: <1μA

Additional Details

The LT3905 is a fixed frequency current-mode step-up converter designed to bias avalanche photodiodes (APD) in optical receivers. The LT3905 features high side APD current monitoring over four decades of dynamic range with better than 2% relative accuracy over the 3μA to 3mA range.

The maximum APD current is programmed with a single resistor, and a fast current limiter with indicator protects the APD during overload conditions. Adjustable output voltage provides dynamic bias control, and an adjustable loss-of-signal indicator flags low APD current.

Coupled with the integrated DMOS power switch and Schottky rectifier, the LT3905 provides a compact total solution with few external components and low solution cost. Constant switching frequency results in predictable output noise that is easy to filter.

The LT3905 is available in the tiny footprint (3mm × 3mm) 16-Lead QFN Package.

Applications

APD Bias
PIN Diode Bias
Optical Receivers and Modules
Fiber Optic Network Equipment

View All Documentation

Ask a Question

Submit your question below and we will return the best answer from ADI’s knowledge database:

Other places you can find help

Support

Analog Devices Support Portal is a one-stop shop to answer all your ADI questions.

Visit the ADI Support Page

Ask the ADI community for help.

Ask the EngineerZone Community

FAQs

Sales & Ordering FAQs

Part Models 4

1ku List Price Starting From $3.07

Technical Documents 3

LT3905: Boost DC/DC Converter with APD Current Monitor Data Sheet 08/08/2014

R570 Reliability Data 03/23/2018

DC1956A - Demo Manual 02/03/2014

Design Resources 4

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal. View our quality and reliability program and certifications for more information.

Part Model	Pin/Package Drawing	Documentation	CAD Symbols, Footprints, and 3D Models
LT3905EUD#PBF	16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)	HTML Material Declaration HTML Reliablity Data	Ultra Librarian SamacSys
LT3905EUD#TRPBF	16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)	HTML Material Declaration HTML Reliablity Data	Ultra Librarian SamacSys
LT3905IUD#PBF	16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)	HTML Material Declaration HTML Reliablity Data	Ultra Librarian SamacSys
LT3905IUD#TRPBF	16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)	HTML Material Declaration HTML Reliablity Data	Ultra Librarian SamacSys

LT3905EUD#PBF
Pin/Package Drawing
16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)
Documentation

HTML Material Declaration

HTML Reliablity Data

CAD Symbols, Footprints, and 3D Models
Ultra Librarian
SamacSys

LT3905EUD#TRPBF
Pin/Package Drawing
16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)
Documentation

HTML Material Declaration

HTML Reliablity Data

CAD Symbols, Footprints, and 3D Models
Ultra Librarian
SamacSys

LT3905IUD#PBF
Pin/Package Drawing
16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)
Documentation

HTML Material Declaration

HTML Reliablity Data

CAD Symbols, Footprints, and 3D Models
Ultra Librarian
SamacSys

LT3905IUD#TRPBF
Pin/Package Drawing
16-Lead QFN (3mm x 3mm x 0.75mm w/ EP)
Documentation

HTML Material Declaration

HTML Reliablity Data

CAD Symbols, Footprints, and 3D Models
Ultra Librarian
SamacSys

PCN/PDN Information

Filter by Model

Part Models

Product Lifecycle

PCN

Apr 11, 2019

- 19_0067

Notification of Wafer Fab Location Change for 0.35 BCD Process

LT3905EUD#PBF

PRODUCTION

LT3905EUD#TRPBF

PRODUCTION

LT3905IUD#PBF

PRODUCTION

LT3905IUD#TRPBF

PRODUCTION

pdf

PCN19_0067_Form

xls

Material_Report

xlsm

Delta Qualification Matrix

pdf

Qualification Results Summary

Detailed Parts List

pdf

Other

Filter by Model

Part Models

Product Lifecycle

PCN

Apr 11, 2019

- 19_0067

Notification of Wafer Fab Location Change for 0.35 BCD Process

LT3905EUD#PBF

PRODUCTION

LT3905EUD#TRPBF

PRODUCTION

LT3905IUD#PBF

PRODUCTION

LT3905IUD#TRPBF

PRODUCTION

pdf

PCN19_0067_Form

xls

Material_Report

xlsm

Delta Qualification Matrix

pdf

Qualification Results Summary

Detailed Parts List

pdf

Other

Companion Parts 1

Parts	Product Life Cycle	Description
Low Voltage Hot Swap Controllers1
LTC4224-1 LTC4224-2		Compact Dual Low Voltage Hot Swap Controller

DC1956A

LT3905 Demo Board | Boost with APD Current Monitor, 2.7V ≤ VIN ≤ 12V, VOUT = 50V @ 2mA

LT3905 Demo Board | Boost with APD Current Monitor, 2.7V ≤ VIN ≤ 12V, VOUT = 50V @ 2mA

Download

DC1956A

LT3905 Demo Board | Boost with APD Current Monitor, 2.7V ≤ VIN ≤ 12V, VOUT = 50V @ 2mA

Buy Now View Details

Product Detail

Demonstration circuit 1956A features the LT3905, a boost DC/DC Converter with APD current monitor that comes in a 3mm × 3mm QFN package. This demo board is designed to convert a 2.7V to 12V input to a 50V output at 2mA. The LT3905 is equipped with indicators for monitoring APD current, overload, and loss-of-signal (LOS) conditions, which can easily be changed with their respective resistors. In addition, the output voltage can be adjusted via the CTRL pin. DC1956A is designed for 1MHz operation but can also be programmed for 2MHz by moving jumper JP2.

Resources

PDF

DC1956A - Demo Manual

174.00K

ZIP

DC1956A - Design File

782.00K

PDF

DC1956A - Schematic

34.00K

DC1956A

LT3905 Demo Board | Boost with APD Current Monitor, 2.7V ≤ VIN ≤ 12V, VOUT = 50V @ 2mA

LTspice 2

LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.

To launch ready-to-run LTspice demonstration circuits for this part:

Step 1: Download and install LTspice on your computer.

Step 2: Click on the link in the section below to download a demonstration circuit.

Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.