2242CKTC Fairchild Semiconductor, 2242CKTC Datasheet



Manufacturer Part Number
Fairchild Semiconductor
• Pin-compatible upgrade of TMC2242B
• User-selectable interpolate d.c. gain, 0 dB or -6 dB
• True unity d.c. gain in all “0 db” modes
• 40 MSPS performance in equal-rate filter modes
• 40 and 60 MSPS speed grades in all other modes
• User-selectable 2:1 decimation, 1:2 interpolation, and
• Defeatable x/sin( x) compensation filter
• Passband ripple <0.014 dB
• Stopband rejection >56 dB
• Dedicated 12-bit two’s complement or unsigned input bus
• 16-bit two’s complement or unsigned output bus with
• Programmable limiter prevents overflow or clips to
• New double-latency modes match Y channel data flow to
• New dual-channel interpolation and decimation for
• Digital-to-Analog Converter Prefiltering with optional
• 1:2 interpolation
• Analog-to-Digital Converter Postfiltering
• 2:1 decimation
• Low-ripple low-pass (0 to 0.2 f
Block Diagram
Digital Half-Band Interpolating/Decimating Filter
12-bit In/16-bit Out, 60 MHz
equal-rate filter modes, plus unfiltered bypass/delay mode
user-selectable rounding to 8 to 16 effective bits
CCIR601 levels
slower-sampled C
x/sinx correction
and C
data flows
) filter
The TMC2242C, a linear-phase low-pass half-band digital
filter with fixed coefficients, can be used to halve or double
the sampling rate of a digital signal. When used as a decimat-
ing post-filter with a double-speed oversampling A/D con-
verter, it greatly reduces the cost and complexity of the
required analog antialiasing pre-filters. When used as an
interpolating pre-filter with a double-speed oversampling
D/A converter, it greatly reduces the complexity and cost of
the necessary analog post-filter, particularly when its x/sin(x)
correction filter is engaged.
The TMC2242C user selects the mode of operation (deci-
mate, interpolate, equal-rate, bypass, x/sin(x))and rounding.
The part can accept 12-bit two’s complement or unsigned
data at up to 60 MHz and can output saturated two’s comple-
ment or offset binary data rounded to from 8 to 16 bits.
Within the speed grade I/O limit, the output sample rate may
be 1/2, 1, or 2 times the input sample rate. Two-channel
modes permit it to interpolate or to decimate two multi-
plexed data streams (such as video C
The filter response is flat to within 0.014 dB up to 0.21f
(e.g. 5.75MHz at a 27MHz clock rate), with stopband attenu-
ation greater than 56dB above 0.29f
filters such as the TMC2242C always have linear phase
response. Half-band response is -6 dB.
Fabricated on an advanced submicron CMOS process, the
TMC2242C is available in a 44-lead PLCC package. Perfor-
mance is guaranteed from 0 to 70 C and over a power supply
range of 4.75 to 5.25V.
. Symmetric-coefficient
and C
) jointly.
Rev. 1.0.0

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2242CKTC Summary of contents

Page 1

TMC2242C Digital Half-Band Interpolating/Decimating Filter 12-bit In/16-bit Out, 60 MHz Features • Pin-compatible upgrade of TMC2242B • User-selectable interpolate d.c. gain • True unity d.c. gain in all “0 db” modes • 40 MSPS performance ...

Page 2

PRODUCT SPECIFICATION Functional Description The TMC2242C implements a fixed-coefficient linear-phase Finite Impulse Response (FIR) filter, with special rate- matching input and output structures for decimation and interpolation. For parts of each speed grade, the faster of either the input or ...

Page 3

TMC2242C Table 2. Package Interconnections Signal Type Name Function Timing CLK Clock SYNC Synchronization Data In SI Input Data Port 11-0 Data Out SO Output Data Port 15-4 Dual- SO Output 3-0 Function Data; Controls Controls INT Interpolate DEC Decimate ...

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PRODUCT SPECIFICATION Pin Descriptions Pin Number Pin Name PLCC MQFP Dedicated Timing Controls CLK 42 36 Clock . The chip operates from a single-phase master clock, to whose rising edges all timing parameters are referenced. All internal registers are strobed ...

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PRODUCT SPECIFICATION Notes: 1. Rounding Operation Detail RND SO Output Rounding 2 000 Output SO 15-0 A 001 Output SO 15-1 010 X SO 15-2 011 X SO 15-3 100 0 SO 15-4 100 1 SO 15-8 101 ...

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PRODUCT SPECIFICATION Operating Conditions V Power Supply Voltage DD f Clock frequency CLK t CLK pulse width, HIGH PWH t CLK pulse width, LOW PWL t Input Data Set-up Time S t Input Data Hold Time H V Input Voltage, ...

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PRODUCT SPECIFICATION Table 3a. Input Data Formats and Bit Weighting Format Two’s Comp Unsigned 2 Table 3b. Output Data Formats and Bit Weighting Format Two’s Comp Unsigned 2 2 ...

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TMC2242C Performance Curves 0 -10 -20 -30 -40 -50 -60 -70 -80 0.00 0.05 0.030 0.025 0.020 0.015 0.010 0.006 0.000 -0.008 -0.010 0.00 110 100 - 0.10 ...

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PRODUCT SPECIFICATION Equivalent Circuits V Digital Input GND Figure 4. Equivalent Digital Input Circuit Timing Diagrams CLK SI 34 11-0 SYNC SO 15 LOW. Note: Values at SO are impulse response centers (peaks) corresponding to same-numbered inputs. 15-0 ...

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TMC2242C 34 CLK SI 11-0 SYNC SO 15 LOW. 68 CLK SI 68 11-0 SYNC 15 LOW. 68 CLK SI 11-0 SYNC SO 15 LOW. Figure 10. Interpolate Mode – Double ...

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PRODUCT SPECIFICATION 34 CLK 11-0 SYNC 15 LOW. *In two-channel modes, sync must be left low after the first data input. 34 CLK SI 11-0 SYNC 15-0 OE ...

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PRODUCT SPECIFICATION Applications Discussion The TMC2242C is well-suited to filtering digitized compos- ite or component NTSC or PAL video. In Figure 14, the TMC1175A 8-bit video A/D converter outputs, D connected to the TMC2242C inputs, SI minimize noise and any ...

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PRODUCT SPECIFICATION Mechanical Dimensions – 44-Pin PLCC Package Inches Millimeters mbol Min. Max. Min. Max. .165 .180 4.19 4.57 .090 .120 2.29 3.05 .020 — .51 — .013 .021 .33 .53 .026 .032 .66 .81 .685 .695 17.40 17.65 E1 ...

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TMC2242C Mechanical Dimensions – 44-Lead MQFP Package Inches Millimeters Symbol Min. Max. Min. A .077 .093 1.95 A1 .000 .010 .00 A2 .077 .083 1.95 B .012 .018 .30 C .005 .009 .13 D/E .510 .530 12.95 D1/E1 .390 .398 ...

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... A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness. PRODUCT SPECIFICATION Package Marking 2242CR2C 2242CR2C1 2242CKTC 2242CKTC1 6/1/99 0.0m 004 Stock#DS7002242C 1998 Fairchild Semiconductor Corporation ...

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