Page 28
Pentek Model 78741 Installation Manual
Rev.: 2.5
2.11
XMC Panel Connections
(continued)
2.11.3
Clock Input Connector
EXT CLK IN
The front panel has one SSMC coaxial connector, labeled
EXT CLK IN
, for
input of an external sample clock for the ADC12D1800 A/D converter.
The external clock signal must be a sine wave of +0 dBm to +10 dBm, with a
frequency range from 150 MHz to 1.8 GHz. In single−channel operation, the
IN 1
input is sampled on both transitions of this clock.
2.11.4
Sync Bus Connector
SYNC/GATE
A front−panel
μ
Sync 19−pin connector, labeled
SYNC\GATE
, provides clock
reset, reference clock, and gate inputs for A/D processing, and a reference
clock output for synchronizing multiple 71741 boards using an external sync
module. These pins are differential 2.5V CML timing signals.
This connector includes TWSI (I
2
C) bus pins for controlling an external sync
module (Pentek Model 7192). Use the TWSI Port 1 Registers (see the
Model
71741 Operating Manual
) to access the external module through these pins.
shows the pin configuration for the
SYNC/GATE
connector. A
mating 18" cable is available from Pentek, Model 2192.
Table 2
−
10: SYNC/GATE Connector Pins
Signal
Pin
Pin
Signal
DCLK_RST_IN_P
1
2
GND
DCLK_RST_IN_N
3
4
GATE_IN_P
GND
5
6
GATE_IN_N
REF_CLK_IN_P
7
8
GND
REF_CLK_IN_N
9
10
REF_CLK_OUT_P
GND
11
12
REF_CLK_OUT_N
n/c
13
14
n/c
TWSI33_SCLK
15
16
TWSI33_SDA
GND
17
18
n/c
n/c
19
1
3
5
7
9
11
13
15
17
19
2
4
6
8
10
12
14
16
18
