![](http://datasheet.mmic.net.cn/370000/TMC2249AH6C_datasheet_16742278/TMC2249AH6C_1.png)
www.fairchildsemi.com
REV. 1.0.2 7/6/00
Features
60 MHz input and computation rate
Two 12-bit multipliers
Separate data and coefficient inputs
Independent, user-selectable pipeline delays of 1 to 16
clocks on all input ports
Separate 16-bit input port allows cascading or addition of
a constant
User-selectable rounded output
Internal 1/2 LSB rounding of products
Fully registered, pipelined architecture
Available in 120-Pin CPGA, PPGA, MPGA or MQFP
Applications
Video switching
Image mixing
Digital signal modulation
Complex frequency synthesis
Digital filtering
Complex arithmetic functions
Description
The TMC2249A is a high-speed digital arithmetic circuit
consisting of two 12-bit multipliers, an adder and a cascade-
able accumulator. All four multiplier inputs are simulta-
neously accessible to the user, and each includes a user-
programmable pipeline delay of up to 16 clocks in length.
The 24-bit adder/subtractor is followed by an accumulator
and 16-bit input port which allows the user to cascade multi-
ple TMC2249As. A new 16-bit accumulated output is avail-
able every clock, up to the maximum rate of 60 MHz. All
inputs and outputs are registered except the three-state out-
put enable, and all are TTL compatible.
Logic Symbol
TMC2249A
Digital Mixer
CLK
NEG1
NEG2
SWAP
OE
ACC
RND
FT
CASEN
S
15-0
Delay
1-16
Delay
1-16
Delay
1-16
Delay
1-16
B
11-0
ADEL
3-0
ENA
A
11-0
BDEL
3-0
ENB
C
11-0
CDEL
3-0
ENC
D
11-0
DDEL
3-0
END
CAB
15-0
The TMC2249A utilizes a pipelined, bus-oriented structure
offering significant flexibility. Input register clock enables
and programmable input data pipeline delays on each port
offer an adaptable input structure for high-speed digital
systems. Following the multipliers, the user may perform
addition or subtraction of either product, arithmetic rounding
to 16 bits, and accumulation and summation of products with a
cascading input. The output port allows access to all 24 bits of
the internal accumulator by switching between overlapping
least and most-significant 16-bit words, and a three-state out-
put enable simplifies connection to an external system bus.
The TMC2249A has numerous applications in digital pro-
cessing algorithms, from executing simple image mixing and
switching, to performing complex arithmetic functions and
complex waveform synthesis. FIR filters, digital quadrature
mixers and modulators, and vector arithmetic functions may
also be implemented with this device.
Fabricated in a submicron CMOS process, the TMC2249A
operates at guaranteed clock rates of up to 60 MHz over the
full temperature and supply voltage ranges. It is pin- and
function-compatible with Fairchild’s TMC2249, while pro-
viding higher speed operation and lower power dissipation. It
is available in a 120 pin Ceramic Pin Grid Array (CPGA),
120 pin Plastic Pin Grid Array (PPGA), 120 lead MQFP to
PPGA package (MPGA), and a 120 lead Metric Quad Flat-
Pack (MQFP).
T MC2249A
Digital Mixer
12 x 12 Bit, 60 MHz