3-200
Pin Description
NAME
TYPE
DESCRIPTION
V
CC
-
+5V Power.
GND
-
Ground.
DATA0-15
I
Input Data Bus. Selectable between two's complement and offset binary. DATA0 is the LSB.
CLK
I
Clock for input data bus. f
S
is the frequency of CLK, which is also the input sample rate.
RESET
I
RESET initializes the internal state of the DDC. During RESET, all internal processing stops. RESET
facilitates the synchronization of multiple chips for Auto Three-State operation. If the Force bits in Control
Word 7 are inactive and the IEEE Test Access Port is in an Idle state, RESET causes the IQCLK, IQSTB,
I and Q outputs to go to a high impedance state.
All Control Registers are updated from their respective Control Buffer Registers on the third rising edge
of CLK after the deassertion of RESET. If RESET is deasserted t
RS
nanoseconds prior to the rising edge
of CLK, the internal reset will deassert synchronously. If t
RS
is violated, then the circuit contains a syn-
chronizer which will cause reset to be deasserted internally one or more clocks later.
An initial reset is required to guarantee proper operation of the DDC. Active low.
I
O
The I output has three modes: I data; I data followed by Q data; real data.
Q
O
The Q output has two modes: Q data and the carry out of the Phase Adder.
IQCLK
O
IQ Clock: Bit or word clock for the I and Q outputs.
IQSTB
O
IQ Strobe: Beginning or end of word indicator for I and Q.
IQSTRT
I
IQ Start: Initiates output data sequence. Active low.
CDATA
I
Control Data: Port for control data input.
CCLK
I
Control Data Clock: Control data input bit clock.
CSTB
I
Control Data Strobe: Beginning of word indicator for control data.
CS
I
Chip Select: Enables control data loading of DDC. Active low.
TCK
I
Test Clock: Bit Clock for IEEE 1149.1 Data. This signal should be either tied low or pulled high when the
TAP is not used.
TMS
I
Test Port Mode Select: This signal should be either left unconnected or pulled high when the TAP is not
used.
TDI
I
Test Data Input for IEEE Test Port: This signal should be either left unconnected or pulled high when the
TAP is not used.
TDO
O
Test Data Output for IEEE Test Port: This output will be in the high impedance state when the TAP is
not used.
TRST
I
Test Port Reset. Active Low. This signal should be tied low when the TAP is not used.
HSP50016