LMU08/8U
DEVICES INCORPORATED
8 x 8-bit Parallel Multiplier
LMU08/8U
8 x 8-bit Parallel Multiplier
DEVICES INCORPORATED
FEATURES
DESCRIPTION
The LMU08 and LMU8U are high-
speed, low power 8-bit parallel
multipliers. They are pin-for-pin
equivalents with TRW TMC208K and
TMC28KU type multipliers. Full
military ambient temperature range
operation is attained by the use of
advanced CMOS technology.
This facilitates use of the LMU08
product as a double precision operand
in 8-bit systems. The LMU8U oper-
ates on unsigned data, producing an
unsigned magnitude result.
❑ 20 ns Worst-Case Multiply Time
❑ LowPowerCMOSTechnology
❑ LMU08 Replaces TRW TMC208K
❑ LMU8UReplacesTRWTMC28KU
❑ Two’sComplement(LMU08),or
Both the LMU08 and the LMU8U
feature independently controlled
registers for both inputs and the
product, which along with three-state
outputs allows easy interfacing with
microprocessor busses. Provision is
Unsigned Operands (LMU8U)
❑ Three-State Outputs
❑ Package Styles Available:
Both the LMU08 and the LMU8U
produce the 16-bit product of two
8-bit numbers. The LMU08 accepts
• 40-pin PDIP
• 44-pinPLCC, J-Lead
operands in two’s complement format, made in the LMU08 and LMU8U for
and produces a two’s complement proper rounding of the product to
result. The product is provided in two 8-bit precision. The round input is
halves with the sign bit replicated as loaded at the rising edge of the logical
the most significant bit of both halves. OR of CLK A and CLK B for the
LMU08. The LMU8U latches RND on
the rising edge of CLK A only. In
either case, a ‘1’ is added in the most
LMU08/8U BLOCK DIAGRAM
significant position of the lower
A
7-0
B7-0
product byte when RND is asserted.
Subsequent truncation of the least
significant product byte results in a
correctly rounded 8-bit result.
8
8
CLK A
CLK B
A REGISTER
B REGISTER
LMU08 Only
RND
16
8
8
CLK R
RESULT
REGISTER
OEM
OEL
8
8
R
15-8
R7-0
Multipliers
08/16/2000–LDS.08/8U-R
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