Max107, Timing requirements – Rainbow Electronics MAX107 User Manual

Page 14

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MAX107

designed for single-ended, low-phase noise sine-wave
clock signals with as little as 500mVp-p amplitude
(-2dBm).

Single-Ended Clock (Sine-Wave Drive)

Excellent performance is obtained by AC- or DC-cou-
pling a low-phase noise sine-wave source into a single
clock input (

Figure 4). Essentially, the dynamic perfor-

mance of the converter is unaffected by clock-drive
power levels from -2dBm (500mVp-p clock signal
amplitude) to +10dBm (2Vp-p clock signal amplitude).
The MAX107 dynamic performance specifications are
determined by a single-ended clock drive of -2dBm

(500mVp-p clock signal amplitude). To avoid saturation
of the input amplifier stage, limit the clock power level
to a maximum of +10dBm.

Differential Clock (Sine-Wave Drive)

The advantages of differential clock drive (Figure 5)
can be obtained by using an appropriate balun or
transformer to convert single-ended sine-wave sources
into differential drives. Refer to Single-Ended Clock
Inputs (Sine-Wave Drive)
for proper input amplitude
requirements.

LVDS, ECL and PECL Clock

The innovative input architecture of the MAX107 clock
also allows these inputs to be driven by LVDS-, ECL- or
PECL-compatible input levels, ranging from 500mVp-p
to 2Vp-p (Figure 6).

Timing Requirements

The MAX107 features a 6:12 demultiplexer, which
reduces the output data rate (including DREADY and
DOR signals) to one-half of the sample clock rate. The
demultiplexed outputs are presented in dual 6-bit two’s
complement format with two consecutive samples in
the primary and auxiliary output ports on the rising

Dual, 6-Bit, 400Msps ADC with On-Chip,
Wideband Input Amplifier

14

______________________________________________________________________________________

AGND

AGND

B

0

°

0

°

0

°

180

°

D

C

A

SIGNAL SOURCE

50

*TERMINATION OF THE UNUSED INPUT/OUTPUT (WITH 50

Ω TO AGND) ON A

BALUN IS RECOMMENDED IN ORDER TO AVOID UNWANTED REFLECTIONS.

CLK+,
INI+,
INQ+

CLK-,
INI-,
INQ-

100pF

100pF

50

50

AGND

50

Ω*

Figure 3. Single-Ended to Differential Conversion Using a Balun

AGND

AGND

FROM SIGNAL SOURCE

CLK+,
INI+,
INQ+

CLK-,
INI-,
INQ-

100pF

100pF

50

Figure 4. Single-Ended Clock Input With AC-Coupled Input
Drive (CLK, INI, INQ)

Figure 5. Differential, AC-Coupled Input Drive (CLK, INI, INQ)

AGND

AGND

50

Ω TRANSMISSION LINES

TO 50

Ω-TERMINATED

SIGNAL SOURCE
OR BALUN

CLK+,
INI+,
INQ+

CLK-,
INI-,
INQ-

100pF

100pF

50

50

50

Ω TRANSMISSION LINES

LVDS LINE DRIVER

SIGNAL
SOURCE
INPUT

CLK+,
INI+,
INQ+

CLK-,
INI-,
INQ-

100pF

100pF

100

Figure 6. LVDS Input Drive (CLK, INI, INQ)

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