LFE2-6E-5TN144CES Lattice Semiconductor, LFE2-6E-5TN144CES Datasheet - Page 26

• Manufacturer Part Number: LFE2-6E-5TN144CES
• Description: Semiconductors and Actives, programmable, Programmable Logic (FPGAs, PALs, CPLDs ...), gate
• Manufacturer: Lattice Semiconductor

Lattice Semiconductor
MAC sysDSP Element
In this case, the two operands, A and B, are multiplied and the result is added with the previous accumulated value.
This accumulated value is available at the output. The user can enable the input and pipeline registers, but the out-
put register is always enabled. The output register is used to store the accumulated value. The Accumulators in the
DSP blocks in the LatticeECP2/M family can be initialized dynamically. A registered overflow signal is also avail-
able. The overflow conditions are provided later in this document. Figure 2-24 shows the MAC sysDSP element.
Figure 2-24. MAC sysDSP
Multiplicand
Multiplier
Signed A
Signed B
Addn
Accumsload
Serial Register B in
n
Register B
Input Data
n
n
SROB
n
Register
Register
Register
Register
Input
Input
Input
Input
m
Input Data
Register A
m
n
SROA
Serial Register A in
m
Register
Register
Register
Register
Pipeline
Pipeline
Pipeline
Pipeline
m
n
2-23
To Accumulator
To Accumulator
To Accumulator
To Accumulator
Multiplier
Pipeline
Register
x
(default)
m+n
LatticeECP2/M Family Data Sheet
Accumulator
CLK (CLK0,CLK1,CLK2,CLK3)
RST(RST0,RST1,RST2,RST3)
CE (CE0,CE1,CE2,CE3)
(default)
m+n+16
Preload
(default)
m+n+16
Architecture
Output
Overflow
signal