4-4
Pin Descriptions
NAME
TYPE
DESCRIPTION
VDD
-
Digital power.
GND
-
Digital ground.
DVDD
-
DAC digital power.
DGND
-
DAC digital ground.
AVDD
-
DAC analog power.
AGND
-
DAC analog ground.
PVDD
-
PLL analog power.
PGND
-
PLL analog ground.
PLLRC
I
PLL loop filter provides for the addition of less expensive RC components in place of a crystal oscillator. The
recommended values for this pin are detailed in the ‘System CLK Generation’ section.
CLK
I
System and DAC clock input when APLL not in use, otherwise it is the reference to the APLL.
SYSCLK/2
O
Sample Clock Divided by Two. All digital output data and status pins are output from this clock. The polarity of
SYSCLK/2 may be programmed via Register 2 bit-3.
2XSYMCLK
O
Tristatable Symbol NCO Clock Output Multiplied by Two. The polarity of 2XSYMCLK may be programmed via
register 2 bit-15.
REFCLK
I
External digital PLL reference clock input.
DIN<15:0>
I
Data Bus. The DIN<15:0> bus loads the input data.
DATACLK
I
Asynchronous data clock for DIN<15:0>.
TXEN
I
DIN<15:0> may be optionally gated with the TXEN pin (burst mode) or input free-running as defined by register 2
bits 18-17. The polarity of TXEN may be programmed via register 2 bit-5.
ISTRB
I
Data samples are input as I then Q serially with the ISTRB pin active with the I sample. The polarity of ISTRB may
be programmed via Register 2 bit-4.
CDATA<7:0>
I/O
μ
P Bidirectional Data Bus. The CDATA<7:0> data bus is used for loading the configuration data and sample vectors
for modulation. CDATA7 is the MSB.
RD
I
μ
P Read control input.
WR
I
μ
P Write strobe input.
CE
I
Chip enable input.
ADDR<2:0>
I
μ
P Address Bus. The ADDR<2:0> bus is used for addressing the proper registers for loading the configuration data
and sample vectors for modulation. ADDR2 is the MSB.
INTREQ
O
Tristatable Active High Interrupt Request Output. The INTREQ output is enabled via register 2 bit-8. Register 9 bits
6-0 enable individual events for INTREQ.
RESET
While the RESET input is asserted (driven low), all processing halts and the WPM is reset. A software reset is also
available via register 10
H
.
IOUT<13:0>
O
Tristatable In-Phase Output Samples. IOUT<13:0> outputs are enabled via register 2 bit-7.
QOUT<13:0>
O
Tristatable Quadrature Output Samples. QOUT<13:0> outputs are enabled via register 2 bit-6. The QOUT<13:0>
outputs are not available on the MQFP package.
FEMPT,
FOVRFL,
FFULL
O
Tristatable Status Flags for FIFO Level Monitoring. These outputs are enabled via register 2 bits 13-11. FIFO status
thresholds and control are configured via register 2 bits 23-16.
LOCKDET
O
Tristatable Status Flag of the Digital PLL. This may be used to generate an interrupt request via INTREQ.
The LOCKDET output is enabled via register 2 bit-10.
IOUTA,
QOUTA
O
Current Outputs of the Device. Full scale output current is achieved when all input bits are set to binary 1.
IOUTB,
QOUTB
O
Complementary Current Outputs of the Device. Full scale output current is achieved on the complementary outputs
when all input bits are set to binary 0.
HSP50415