Altera iopll ip core parameters - settings tab – Altera I/O Phase-Locked Loop (Altera IOPLL) IP Core User Manual
Page 4

Parameter
Legal Value
Description
Multiply Factor (M-
Counter)
(2)
4–511
Specifies the multiply factor of
M
-counter.
The legal range of the
M
counter is 4–511. However, restric‐
tions on the minimum legal PFD frequency and maximum
legal VCO frequency restrict the effective
M
counter range to
4–160.
Divide Factor (N-
Counter)
(2)
1–511
Specifies the divide factor of
N
-counter.
The legal range of the
N
counter is 1–511. However, restric‐
tions on the minimum legal PFD frequency restrict the
effective range of the
N
counter to 1–80.
Divide Factor (C-
Counter)
(2)
1-511
Specifies the divide factor for the output clock (
C
-counter).
Altera IOPLL IP Core Parameters - Settings Tab
Table 2: Altera IOPLL IP Core Parameters - Settings Tab
Parameter
Legal Value
Description
PLL Bandwidth Preset
Low, Medium,
or High
Specifies the PLL bandwidth preset setting. The default
selection is Low.
PLL Auto Reset
Turn on or
Turn off
Automatically self-resets the PLL on loss of lock.
Create a second input clk
‘refclk1’
Turn on or
Turn off
Turn on to provide a backup clock attached to your PLL
that can switch with your original reference clock.
Second Reference Clock
Frequency
—
Selects the frequency of the second input clock signal. The
default value is 100.0 MHz. The minimum and maximum
value is dependent on the device used.
Create an ‘active_clk’ signal
to indicate the input clock
in use
Turn on or
Turn off
Turn on to create the
activeclk
output. The
activeclk
output indicates the input clock which is in use by the PLL.
Output signal low indicates
refclk
and output signal high
indicates
refclk1
.
Create a ‘clkbad’ signal for
each of the input clocks
Turn on or
Turn off
Turn on to create two
clkbad
outputs, one for each input
clock. Output signal low indicates the clock is working and
output signal high indicates the clock is not working.
(2)
This parameter is only available when Enable physical output clock parameters is turned on.
4
Altera IOPLL IP Core Parameters - Settings Tab
UG-01155
2015.05.04
Altera Corporation
Altera I/O Phase-Locked Loop (Altera IOPLL) IP Core User Guide