REVISION D 07/13/15 7 PROGRAMMABLE FANOUT BUFFER
5P1103 DATASHEET
its independent output power pin (V
DDO
) and thus each can
have different output voltage levels. Output voltage levels of
2.5V or 3.3V are supported for differential HCSL, LVPECL
operation, and 1. 8V, 2.5V, or 3.3V are supported for LVCMOS
and differential LVDS operation.
Each output may be enabled or disabled by register bits.
When disabled an output will be in a logic 0 state as
determined by the programming bit table shown on page 6.
LVCMOS Operation
When a given output is configured to provide LVCMOS levels,
then both the OUTx and OUTxB outputs will toggle at the
selected output frequency. All the previously described
configuration and control apply equally to both outputs.
Frequency, phase alignment, voltage levels and enable /
disable status apply to both the OUTx and OUTxB pins. The
OUTx and OUTxB outputs can be selected to be
phase-aligned with each other or inverted relative to one
another by register programming bits. Selection of
phase-alignment may have negative effects on the phase
noise performance of any part of the device due to increased
simultaneous switching noise within the device.
Device Hardware Configuration
The 5P1103 supports an internal One-Time Programmable
(OTP) memory that can be pre-programmed at the factory
with up to 4 complete device configuration.
These configurations can be over-written using the serial
interface once reset is complete. Any configuration written via
the programming interface needs to be re-written after any
power cycle or reset. Please contact IDT if a specific
factory-programmed configuration is desired.
Device Start-up & Reset Behavior
The 5P1103 has an internal power-up reset (POR) circuit. The
POR circuit will remain active for a maximum of 10ms after
device power-up.
Upon internal POR circuit expiring, the device will exit reset
and begin self-configuration.
The device will load internal registers using the configuration
stored in the internal One-Time Programmable (OTP)
memory.
Once the full configuration has been loaded, the device will
respond to accesses on the serial port and will attempt to
begin operation.
Power Up Ramp Sequence
VDDA and VDDD must ramp up together. VDDO0~2 must
ramp up before, or concurrently with, VDDA and VDDD. All
power supply pins must be connected to a power rail even if
the output is unused. All power supplies must ramp in a linear
fashion and ramp monotonically.