AD9510-VCO/PCB Analog Devices Inc, AD9510-VCO/PCB Datasheet - Page 56

• Manufacturer Part Number: AD9510-VCO/PCB
• Description: BOARD EVAL CLOCK DISTR 64LFCSP
• Manufacturer: Analog Devices Inc

Specifications of AD9510-VCO/PCB

• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

AD9510
POWER SUPPLY
The AD9510 requires a 3.3 V ± 5% power supply for V
The tables in the Specifications section give the performance
expected from the AD9510 with the power supply voltage
within this range. The absolute maximum range of −0.3 V −
+3.6 V, with respect to GND, must never be exceeded on
the VS pin.
Good engineering practice should be followed in the layout of
power supply traces and the ground plane of the PCB. The
power supply should be bypassed on the PCB with adequate
capacitance (>10 μF). The AD9510 should be bypassed with
adequate capacitors (0.1 μF) at all power pins as close as
possible to the part. The layout of the AD9510 evaluation board
(AD9510/PCB or AD9510-VCO/PCB) is a good example.
The AD9510 is a complex part that is programmed for its
desired operating configuration by on-chip registers. These
registers are not maintained over a shutdown of external power.
This means that the registers can loose their programmed
values if V
collapse. Careful bypassing should protect the part from
memory loss under normal conditions. Nonetheless, it is
important that the V
or the AD9510 risks losing its programming.
The internal bias currents of the AD9510 are set by the R
CPR
the values given as conditions in the Specifications section
(R
1% resistor values, and should be readily obtainable. The bias
currents set by these resistors determine the logic levels and
operating conditions of the internal blocks of the AD9510. The
performance figures given in the Specifications section assume
that these resistor values are used.
The VCP pin is the supply pin for the charge pump (CP). The
voltage at this pin (V
to match the tuning voltage range of a specific VCO/VCXO.
This voltage must never exceed the absolute maximum of 6 V.
V
V
CP
S
SET
or GND, whichever is lower.
should also never be allowed to be less than −0.3 V below
SET
= 4.12 kΩ and CPR
resistors. These resistors should be as close as possible to
S
is lost long enough for the internal voltages to
S
CP
power supply not become intermittent,
) may be from V
SET
= 5.1 kΩ). These values are standard
S
up to 5.5 V, as required
S
.
SET
and
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The exposed metal paddle on the AD9510 package is an
electrical connection, as well as a thermal enhancement. For
the device to function properly, the paddle must be properly
attached to ground (GND). The PCB acts as a heat sink for the
AD9510; therefore, this GND connection should provide a
good thermal path to a larger dissipation area, such as a ground
plane on the PCB. See the layout of the AD9510 evaluation
board (AD9510/PCB or AD9510-VCO/PCB) for a good
example.
POWER MANAGEMENT
The power usage of the AD9510 can be managed to use only the
power required for the functions that are being used. Unused
features and circuitry can be powered down to save power. The
following circuit blocks can be powered down, or are powered
down when not selected (see the Register Map and Description
section):
• The PLL section can be powered down if not needed.
• Any of the dividers are powered down when bypassed—
• The adjustable delay blocks on OUT5 and OUT6 are powered
• Any output may be powered down. However, LVPECL
• The entire distribution section can be powered down when
Powering down a functional block does not cause the
programming information for that block (in the registers)
to be lost. This means that blocks can be powered on and off
without otherwise having to reprogram the AD9510. However,
synchronization is lost. A SYNC must be issued to
resynchronize (see the Single-Chip Synchronization section).
equivalent to divide-by-one.
down when not selected.
outputs have both a safe and an off condition. When the
LVPECL output is terminated, only the safe shutdown should
be used to protect the LVPECL output devices. This still
consumes some power.
not needed.