Maxim MAX12557 manual TWO-TONE IMD Plot 16,384-POINT Data Record

Dual, 65Msps, 14-Bit, IF/Baseband ADC

Typical Operating Characteristics (continued)

(VDD = 3.3V, OVDD = 2.0V, GND = 0, REFIN = REFOUT (internal reference mode), CL ≈ 5pF at digital outputs, VIN = -0.5dBFS, DIFFCLK/SECLK = OVDD, PD = GND, G/T = GND, fCLK = 65MHz (50% duty cycle), TA = +25°C, unless otherwise noted.)

MAX12557

FFT PLOT (32,768-POINT DATA RECORD)

	0	fCLK = 65.00352MHz					toc04		0
	-10								-10
		fIN = 174.98857MHz					MAX12557
	-20								-20
		AIN = -0.476dBFS
(dBFS)	-30	SNR = 72.37dB						(dBFS)	-30
	-40	SINAD = 70.48dB							-40
		THD = -75.62dBc
	-50								-50
		SFDR = 76.37dBc
AMPLITUDE								AMPLITUDE
	-60		HD3				HD2		-60
	-70								-70
	-80								-80
	-90								-90
	-100								-100
	-110								-110
	-120						30		-120
	0	5	10	15	20	25

TWO-TONE IMD PLOT

(16,384-POINT DATA RECORD)

				fCLK = 65.00352MHz			toc05		0
									-10
				fIN1 = 68.49987MHz			MAX12557
									-20
				AIN1 = -6.97dBFS
		fIN2		fIN2 = 71.49930dB					-30
				AIN2 = -6.99dBFS				(dBFS)	-40
	fIN1			IM3 = -91.54dBc
									-50
				IMD = -87.97dBc
								AMPLITUDE
									-60
		2fIN1 + fIN2		2fIN2 + fIN1					-70
				HD3					-80
									-90
									-100
									-110
0	5	10	15	20	25	30			-120

TWO-TONE IMD PLOT

(16,384-POINT DATA RECORD)

	fCLK = 65.00352MHz					toc06
						MAX12557
	fIN1 = 172.49995MHz
	AIN1 = -6.95dBFS
	fIN2 = 177.49900688MHz
	AIN2 = -6.97dBFS
	IM3 = -87.61dBc			fIN1	fIN2
	IMD = -82.37dBc
					fIN1 + fIN2
		HD3				HD2
0	5	10	15	20	25	30

ANALOG INPUT FREQUENCY (MHz) ANALOG INPUT FREQUENCY (MHz)

ANALOG INPUT FREQUENCY (MHz)

INTEGRAL NONLINEARITY	DIFFERENTIAL NONLINEARITY
vs. DIGITAL OUTPUT CODE	vs. DIGITAL OUTPUT CODE	SNR, SINAD vs. ANALOG INPUT FREQUENCY
(4,194,304-POINT DATA RECORD)	(4,194,304-POINT DATA RECORD)	(fCLK = 65.00352MHz, AIN = -0.5dBFS)

	2.0					toc07MAX12557	1.00					toc08MAX12557	80								toc09MAX12557
					fIN = 3.00123MHz
	1.5						0.75					fIN = 3.00123MHz	75
																			SNR
(LSB)INL	1.0					DNL(LSB)	0.50					SINADSNR,(dB)	70
	-0.5						-0.25						55
	0.5						0.25						65
	0						0						60			SINAD
	-1.0						-0.50						50
	-1.5						-0.75						45
	-2.0						-1.00						40
	0	2048	4096	6144	8192 10240 12288 14336 16384			0	2048	4096	6144	8192 10240 12288 14336 16384	0	50	100	150	200	250	300	350	400
			DIGITAL OUTPUT CODE							DIGITAL OUTPUT CODE						fIN (MHz)

-THD, SFDR vs. ANALOG INPUT FREQUENCY	SNR, SINAD vs. ANALOG INPUT AMPLITUDE	-THD, SFDR vs. ANALOG INPUT AMPLITUDE
(fCLK = 65.00352MHz, AIN = -0.5dBFS)	(fCLK = 65.00352MHz, fIN = 70MHz)	(fCLK = 65.00352MHz, fIN = 70MHz)

	95								toc10		80
	90								MAX12557		70
	85
					SFDR
SFDR (dBc)	80									SINAD (dB)	60
	75										50
	70		-THD
THD,										SNR,
											40
-	65
	60										30
	55
	50										20
	0	50	100	150	200	250	300	350	400

		toc11	95
SNR
		MAX12557
			85
		SFDR (dBc)	75
SINAD			65
		-THD,
			55
			45
-55 -50 -45 -40 -35 -30 -25 -20 -15 -10	-5	0	35

		toc12
SFDR		MAX12557
-THD
-55 -50 -45 -40 -35 -30 -25 -20 -15 -10	-5	0

fIN (MHz)

AIN (dBFS) AIN (dBFS)

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