(Preliminary)
PL611s-19
0.5kHz-55MHz MHz to KHz Programmable Clock
TM
FUNCTIONAL DESCRIPTION
PL611s-19 is a highly featured, very flexible, advanced programmable PLL design for high performance, low-
power, small form-factor applications. The PL611s-19 accepts a reference clock input of 1MHz to 200MHz and is
capable of producing two outputs up to 125MHz. This flexible design allows the PL611s-19 to deliver any PLL
generated frequency, F
REF
(Ref Clk) frequency or F
REF
/(2*P) to CLK0 and/or CLK1. Some of the design features
of the PL611s-19 are mentioned below:
PLL Programming
The PLL in the PL611s-19 is fully programmable.
The PLL is equipped with an 5-bit input frequency
divider (R-Counter), and an 8-bit VCO frequency
feedback loop divider (M-Counter). The output of
the PLL is transferred to a 14-bit post VCO divider
(P-Counter). The output frequency is determined by
the following formula [F
OUT
= F
REF
* M / (R * P) ].
Clock Output (CLK0)
The output of CLK0 can be configured as the PLL output
(F
VCO
/(2*P)), F
REF
(Ref Clk Frequency) output, or
F
REF
/(2*P) output. The output drive level can be
programmed to Low Drive (4mA), Standard Drive
(8mA) or High Drive (16mA). The maximum output
frequency is 125MHz.
Clock Output (CLK1)
The output of CLK1 can be configured as:
F
REF
- Reference ( Ref Clk ) Frequency
F
REF
/ 2
CLK0
CLK0 / 2
When using the OE function CLK1 will remain
“Always On” and will not be disabled when OE is
pulled low. When using the PDB function CLK1 will
be disabled along with CLK0. The output drive level
can be programmed to Low Drive (4mA), Standard
Drive (8mA) or High Drive (16mA). The maximum
output frequency is 125MHz.
Programmable I/O (OE/PDB/FSEL)
The PL611s-19 provides one programmable I/O pin
which can be configured as one of the following
functions:
Output Enable (OE)
The Output Enable feature allows the user to enable
and disable CLK0 clock output by toggling the OE
pin. CLK1 remains active when OE is pulled low.
The OE pin incorporates a 60k pull up resistor
giving a default condition of logic “1”.
The OE feature can be programmed to allow the
output to float (Hi Z), or to operate in the ‘Active low’
mode.
Power-Down Control (PDB)
The Power Down (PDB) feature allows the user to put
the PL611s-19 into “Sleep Mode”. When activated
(logic ‘0’), PDB ‘Disables the PLL, the oscillator
circuitry, counters, and all other active circuitry. In
Power Down mode the IC consumes <5 A of power.
The PDB pin incorporates a 60k pull up resistor
giving a default condition of logic “1”.
The PDB feature can be programmed to allow the
output to float (Hi Z), or to operate in the ‘Active low’
mode.
Frequency Select (FSEL)
The Frequency Select (FSEL) feature allows the
PL611s-19 to switch between two pre-programmed
outputs allowing the device “On the Fly” frequency
switching. The FSEL pin incorporates a 60k pull up
resistor giving a default condition of logic “1”.
47745 Fremont Blvd., Fremont, California 94538 Tel (510) 492-0990 Fax (510) 492-0991
www.phaselink.com
Rev 12/12/06 Page 3
PLL [ PHASELINK CORPORATION ]
