Maxim MAX12557 manual Pin Configuration, Gain Matching, Offset Matching

Page 27

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

Gain Matching

Gain matching is a figure of merit that indicates how well the gains between the two channels are matched to each other. The same input signal is applied to both channels and the maximum deviation in gain is report- ed (typically in dB) as gain matching.

Offset Matching

Like gain matching, offset matching is a figure of merit that indicates how well the offsets between the two chan- nels are matched to each other. The same input signal is applied to both channels and the maximum deviation in offset is reported (typically in %FSR) as offset matching.

Pin Configuration

TOP VIEW

REFOUT

SHREF

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

REFIN

PD

G/T

DD

DD

DD

DD

DORA

D13A

D12A

D11A

D10A

D9A

D8A

D7A

 

 

V

V

V

OV

 

 

68

67

66

65

64

63

62

61

60

59

58

57

56

55

54

53

52

 

GND

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

51

D6A

INAP

2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

50

D5A

INAN

3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

49

D4A

GND

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

48

D3A

GND

5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

47

D2A

COMA

6

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

46

D1A

REFAP

7

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

45

D0A

REFAN

8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

44

DAV

GND

9

 

 

 

 

 

 

MAX12557

 

 

 

 

 

 

43

OVDD

REFBN

10

 

 

 

 

 

 

 

 

 

 

 

 

42

DORB

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

REFBP

11

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

41

D13B

COMB

12

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

40

D12B

GND

13

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

39

D11B

GND

14

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

38

D10B

INBN

15

 

EXPOSED PADDLE (GND)

 

 

 

 

 

 

 

 

37

D9B

INBP

16

 

 

 

 

 

 

 

 

 

 

D8B

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

36

GND

17

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

35

D7B

 

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

 

 

DIFFCLK/SECLK

CLKN

CLKP

DIV2

DIV4

DD

DD

DD

DD

DD

D0B

D1B

D2B

D3B

D4B

D5B

D6B

 

 

V

V

OV

 

 

V

V

THIN QFN

 

 

 

 

 

 

 

MAX12557

______________________________________________________________________________________ 27

Image 27
Contents Ordering Information FeaturesGeneral Description ApplicationsConversion Rate Parameter Symbol Conditions MIN TYP MAX Units DC AccuracyDynamic Characteristics differential inputs Analog Input INAP, INAN, INBP, InbnParameter Symbol Conditions MIN TYP MAX Units Interchannel Characteristics Internal Reference RefoutVcom Digital Inputs DIFFCLK/ SECLK, G/ T, PD, DIV2, DIV4 Clock Inputs CLKP, ClknDIFFCLK/ Seclk = GND, Clkn = GND DIFFCLK/ Seclk = OV DDDIFFCLK/SECLK = Ovdd Power RequirementsD0A-D13A, Dora DIFFCLK/SECLK = GNDTypical Operating Characteristics Timing Characteristics FigureFFT Plot 32,768-POINT Data Record TWO-TONE IMD Plot 16,384-POINT Data Record MAX12557FIN = 70MHz, AIN = -0.5dBFS THD, Sfdr vs. Clock SpeedSNR, Sinad vs. Clock Duty Cycle FIN = 70MHz, AIN = -0.5dBFS FCLK = 65.00352MHz, fIN = 175MHzPDISS, Iovdd Digital Vs. Digital Supply Voltage FCLK = 65.00352MHz, fIN = 175MHzGain Error vs. Temperature Pin Description PIN Name FunctionSame side of the PC board D3B D0BD1B D2BRefin Detailed DescriptionShref RefoutFunctional Diagram Reference Output Reference ConfigurationsReference Mode Analog Inputs and Input Track-and-Hold T/H AmplifierClock Input and Clock Control Lines Clock Duty-Cycle EqualizerSystem Timing Requirements Data-Valid OutputDIV4 DIV2 Function Output Codes vs. Input Voltage Vrefp Vrefn Power-Down InputBinary-to-Gray and Gray-to-Binary Code Conversion Using Transformer Coupling Single-Ended AC-Coupled Input SignalApplications Information Unbuffered External Reference Drives Multiple ADCs Buffered External Reference Drives Multiple ADCsMAX12557 Grounding, Bypassing, and Board LayoutParameter Definitions Total Harmonic Distortion THD Aperture DelayFull-Power Bandwidth Overdrive Recovery TimePin Configuration Gain MatchingOffset Matching 68L QFN THIN.EPS Package Information