Rainbow Electronics MAX19515 - Manual (Page 24)

Clock Inputs
The input clock interface provides for flexibility in the
requirements of the clock driver. The MAX19515
accepts a fully differential clock or single-ended logic-
level clock. For differential clock operation, connect a
differential clock to the CLK+ and CLK- inputs. In this
mode, the input common mode is established internally
to allow for AC-coupling. The differential clock signal
can also be DC-coupled if the common mode is con-
strained to the specified 1V to 1.4V clock input com-
mon-mode range. For single-ended operation, connect
CLK- to GND and drive the CLK+ input with a logic-
level signal. When the CLK- input is grounded (or
pulled below the threshold of the clock mode detection
comparator) the differential-to-single-ended conversion
stage is disabled and the logic-level inverter path is
activated.
Clock Divider
The MAX19515 offers a clock-divider option. Enable
clock division either by setting DIV0 and DIV1 through
the serial interface; see the Clock Divide/Data
MAX19515
Dual-Channel, 10-Bit, 65Msps ADC
24 ______________________________________________________________________________________
CLK+
100 Ω
TERMINATION
(PROGRAMMABLE)
SELF-BIAS TURNED OFF FOR
SINGLE-ENDED CLOCK
OR POWER-DOWN.
CLK-
GND
AVDD
10k Ω
20k Ω
5k Ω
5k Ω
50 Ω
50 Ω
2:1 MUX
SELECT
THRESHOLD
Figure 8. Simplified Clock Input Schematic
DCLK
DATA, DOR
SAMPLE CLOCK
n n+1
SAMPLE ON RISING EDGE
n+2 n+4 n+5
n-9 n-8 n-10 n-7 n-6 n-5 n-4
t CLK
t SETUP
t CH
t
DD
t DC
t HOLD
t
CL
DUAL-BUS OUTPUT MODE
SAMPLE CLOCK IS THE DERIVED CLOCK FROM (CLK+ - CLK-)/CLOCK DIVIDER, IN_ = IN_+ - IN_-.
SAMPLING
INSTANT
SAMPLING
INSTANT
SAMPLING
INSTANT
SAMPLING
INSTANT SAMPLING
INSTANT
SAMPLING
INSTANT
IN_
t
AD
n+3
Figure 9. Dual-Bus Output Mode Timing