Features Gain range 40 dB Gain step size 2 dB Combined gain resolution with Gsample/second ADC’s 8.5 mdB Min gain −1.16 dB Max gain 38.8 dB −3 dB BW 900 MHz Rise/fall time <500 ps Recovery time <5 ns Propagation delay variation 100 ps HD2 @ 100 MHz −50 dBc HD3 @ 100 MHz −53 dBc Input-referred noise (max gain) 0.98 nV/ √Hz Over-voltage clamps for fast recovery Power consumption  — Auxiliary turned off 1.1W 0.75W Description The LMH6518 is a digitally controlled variable gain amplifier whose total gain can be varied from −1.16 dB to 38.8 dB for a 40 dB range in 2 dB steps. The −3 dB bandwidth is 900 MHz at all gains. Gain accuracy at each setting is typically 0.1 dB. When used in conjunction with a National Semiconductor Gsample/second (Gsps) ADC with adjustable full scale (FS) range, the LMH6518 gain adjustment will accommodate full scale input signals from 6.8 mVPP to 920 mVPP to get 700 mVPP nominal at the ADC input. The Auxiliary output (“+OUT Aux” and “−OUT Aux”) follows the Main output and is intended for use in Oscilloscope trigger function circuitry but may have other uses in other applications. The LMH6518 gain is programmed via a SPI-1 compatible serial bus. A signal path combined gain resolution of 8.5 mdB can be achieved when the LMH6518’s gain and the Gsps ADC’s FS input are both manipulated. Inputs and outputs are DC-coupled. The outputs are differential with individual Common Mode (CM) voltage control (for Main and Auxiliary outputs) and have a selectable bandwidth limiting circuitry (common to both Main and Auxiliary) of 20, 100, 200, 350, 650, 750 MHz or full bandwidth. Applications Oscilloscope programmable gain amplifier Differential ADC drivers High frequency single-ended input to differential conversion Precision gain control applications Medical applications RF/IF applications

Also Recommended ADC08500 500Msps ADC ADC08D1020 Dual 1Gsps ADC ADC08D1520 Dual 1.5Gsps ADC ADC08D500 Dual 500Msps ADC

	Block Diagram *click for larger image
Typical Performance click for larger image

Parameters Values Gain Adjust Range 40 dB Signal Channel BW 900 MHz Supply Min 4.75 Volt Supply Max 5.25 Volt Gain Control Interface SPI-1 Supply Current 150 mA PowerWise Rating 2 167 uA/MHz Offset Voltage max, 25C 40 mV Max Input Bias Current 10000 nA Voltage Noise 0.98 nV/root(Hz) HD 2nd -50 dB HD 3rd -53 dB Special Features Oscilloscope Front-end w/ Trigger & Filters Function VGA Temperature Min -40 deg C Temperature Max 85 deg C Automotive No PowerWise Yes

Datasheets

Title		Size	Date	Other Language
	LMH6518 900 MHz, Digitally Controlled, Variable Gain Amplifier	866 Kbytes	6-Oct-08

Application Notes

Title		Size	Date	Other Language
	AN-1906: Application Note 1906 LMH6518 Evaluation Board	965 Kbytes	23-Oct-08
	AN-1718: Application Note 1718 Differential Amplifier Applications Up to 400 MHz	154 Kbytes	14-Nov-07	日本語 中文

Part Number(s) (NSID)	Top View	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LMH6518SQ/NOPB RoHS Status	LLP	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0	$6.00 each at 100+ pcs	reel of 1000
LMH6518SQE/NOPB RoHS Status	LLP	Full production Lead Time: 6 weeks	Distributor Region Qty ARROW Worldwide 272 AVNET-EM Worldwide 250 DIGI-KEY Worldwide 528 FARNELL Europe and Asia 248 MOUSER Worldwide 250 NEWARK Americas 248 TAYLOR Americas 272	$6.00 each at 100+ pcs	reel of 250
LMH6518SQX/NOPB RoHS Status	LLP	Full production Lead Time: 6 weeks	Distributor Region Qty DIGI-KEY Worldwide 0	$6.00 each at 100+ pcs	reel of 4500

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LMH6518.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LMH6518 is located at RoHS Status.

Part Number(s) (NSID)	Description	Availability	Current Reported Stock	Budgetary Pricing	Pack Size
LMH6518SQEVK	Evaluation Kit for the LMH6518	Full production	Distributor Region Qty DIGI-KEY Worldwide 0 MOUSER Worldwide 1	$250.00 each	1
Description: The LMH6518 evaluation board (part # LMH6518SQEVAL) is designed to aid in the characterization of National Semiconductors High Speed LMH6518 Digitally Controlled Variable Gain Amplifier (DVGA). Use the evaluation board as a guide for high frequency layout and as a tool to aid in device testing and characterization. Contents: A Fully Assembled LMH6518SQ Evaluation Board USB Interface Module (for SPI communication) Evaluation Board to USB Interface Module Interconnect Cable USB Cable Application Note 1906 LMH6518 Evaluation Board Resources: LMH6518 Datasheet for the 900 MHz, Digitally Controlled, Variable Gain Amplifier Application Note 1906 LMH6518 Evaluation Board The latest version of the software GUI (required) for this kit may be downloaded by clicking on Software Setup Files. Microsoft.net framework is necessary and available by clicking on Microsoft.net Version 2.0 Evaluation board information is available by clicking on Schematic, BOM and layout images Information on the USB Interface Module (for SPI communication) is available by clicking on USB Interface Module Evaluation Board to USB Interface Module Interconnect Cable information

National Semiconductor follows the provisions of the Product Stewardship Guide for Customers (CSP-9-111C1) and Banned Substances and Materials of Interest Specification (CSP-9-111S2) for regulatory environmental compliance. Details may be found at: www.national.com/en/packaging/greennopb.html. Lead free products are RoHS compliant.

Lead Free product status is available through the search tool located here

Part Number(s) (NSID)	Weight (milligrams)	Type	Pins	MSL Rating	Peak Reflow	RoHS Status	CAD Symbols	Models	Package Marking Format
LMH6518SQ/NOPB	39.461	LLP	16	3	260	Detail	Download	N/A	NS UZXYTT L6518SQ
LMH6518SQE/NOPB	39.461	LLP	16	3	260	Detail	Download	N/A	NS UZXYTT L6518SQ
LMH6518SQX/NOPB	39.461	LLP	16	3	260	Detail	Download	N/A	NS UZXYTT L6518SQ

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LMH6518.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LMH6518 is located at RoHS Status.

Design Tools

Title	Size	Date
"Board Schematic, BOM and layout images documentation"
LMH6518 Application Information FS Gain ECM Calculator

CAD Symbols and Models Download LMH6518 CAD Symbols

Models N/A

Reliability Metrics

Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LMH6518SQ	BICMOS8B+	0	3632	0	0	2762292	2	783807897
LMH6518SQE	BICMOS8B+	0	3632	0	0	2762292	2	783807897
LMH6518SQX	BICMOS8B+	0	3632	0	0	2762292	2	783807897

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.

All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

Moisture Sensitivity Level Data for LMH6518.

A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

National's certificate of product compliance for LMH6518 is located at RoHS Status.

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Software-Defined Radio (SDR) Webinar Date: 2010-08-30 Length: 0:28:23