5. Output Clock Terminations
The Si5332 supports output formats of LVCMOS, LVDS, LVPECL, and HCSL with some additional format specific features. Each out-
put driver is individually programmable to any of the supported formats by use of the following registers.
Table 5.1. Output Format Related Register Fields
outx_mode
: - Sets the mode of the driver. See
Table 5.2 OUTx_Mode vs Output Formats on page 11
outx_cmos_inv
: - Sets the inversion state of each side of the dual output driver when in CMOS driver format.
outx_cmos_slew
: - Sets the slew rate of the CMOS driver.
outx_cmos_str
: - Sets the output impedance of the CMOS driver (25Ω / 50Ω).
Table 5.2. OUTx_Mode vs Output Formats
OUTx_MODE
Driver Mode
0
off
1
CMOS on positive output only
2
CMOS on negative output only
3
dual CMOS outputs
4
2.5V/3.3V LVDS
5
1.8V LVDS
6
2.5V/3.3V LVDS fast
7
1.8V LVDS fast
8
HCSL 50 Ω (external termination)
9
HCSL 50 Ω (internal termination)
10
HCSL 42.5 Ω (external termination)
11
HCSL 42.5 Ω (internal termination)
12
LVPECL
13
Reserved
14
Reserved
15
Reserved
The recommended termination for each output format is shown in these figures:
Figure 5.1 LVCMOS Termination, Option 1 on page
Figure 5.2 LVCMOS Termination, Option 2 on page 12
.
Si5332-AM1/2/3 Automotive Grade Device Reference Manual
Output Clock Terminations
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