FAIRCHILD TMC2242CKTC1

www.fairchildsemi.com
TMC2242C
Digital Half-Band Interpolating/Decimating Filter
12-bit In/16-bit Out, 60 MHz
Features
Description
•
•
•
•
•
•
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 decimating post-filter with a double-speed oversampling A/D converter, 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.
•
•
•
•
•
•
•
•
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
equal-rate filter modes, plus unfiltered bypass/delay mode
Defeatable πx/sin(πx) 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
user-selectable rounding to 8 to 16 effective bits
Programmable limiter prevents overflow or clips to
CCIR601 levels
New double-latency modes match Y channel data flow to
slower-sampled CB and CR data flows
New dual-channel interpolation and decimation for
YUV422
Applications
• Digital-to-Analog Converter Prefiltering with optional
x/sinx correction
• 1:2 interpolation
• Analog-to-Digital Converter Postfiltering
• 2:1 decimation
• Low-ripple low-pass (0 to 0.2 fs) filter
The TMC2242C user selects the mode of operation (decimate, 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 complement 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 multiplexed data streams (such as video CB and CR) jointly.
The filter response is flat to within ±0.014 dB up to 0.21fs
(e.g. 5.75MHz at a 27MHz clock rate), with stopband attenuation greater than 56dB above 0.29fs. Symmetric-coefficient
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. Performance is guaranteed from 0 to 70°C and over a power supply
range of 4.75 to 5.25V.
Block Diagram
SI11-0
ZERO
INSERT
X/SIN(X)
FILTER
FIR
FILT
ROUND
LIMIT
DECIMATE
SO15-0
SO3-0
CONTROL
65-2242C-01
DEC
INT
SYNC TCO RND
OE
Rev. 1.0.0
PRODUCT SPECIFICATION
Functional Description
The TMC2242C implements a fixed-coefficient linear-phase
Finite Impulse Response (FIR) filter, with special ratematching input and output structures for decimation and
interpolation. For parts of each speed grade, the faster of
either the input or the output bus will operate at the respective guaranteed maximum clock rate. The total internal
pipeline latency from the input of an impulse to the corresponding output peak (digital group delay) is 34 clock
cycles; the 39-value output response begins after 15 clock
cycles and ends after 53 cycles. (The double-latency interpolation and decimation modes feature group delays of 68
clock cycles.)
TMC2242C
and other special modes. Unless more than 12 output bits are
enabled, the TMC2242C offers x/sin(x) correction filtering,
with or without the main low-pass filter, and without impacting the 34-cycle group delay. Bidirectional pins SO3-2
enable these modes, per Table 1. If 14 or more output bits are
used, the low pass filter remains enabled, the x/sin(x),
disabled.
Table 1. Operating Modes
INT
DEC RND2 SO3-2
Function
0
0
0
Output
Interpolate (0 dB)
0
1
0
Output
Interpolate1 (-6 dB)
1
0
0
Output
Decimate
To interpolate, the chip accepts incoming data on alternate
clock cycles, inserting zeroes on the remaining clock cycles.
In decimation mode, the chip’s output register is strobed at
half the clock rate. In bypass and equal-rate filter modes,
these input zero insertion and output register hold functions
are disabled.
1
1
0
Output
Equal Rate Lowpass
0
0
1
00
Interpolate (0 dB)
0
1
1
00
Interpolate1 (-6 dB)
1
0
1
00
Decimate
1
1
1
00
Equal Rate Lowpass
When interpolating, the user should normally bring SYNC
HIGH for at least one clock cycle, returning it LOW with the
first desired input data value. The chip will then continue to
accept data on alternate rising edges of CLK. The user may
leave SYNC LOW or change its value once per clock cycle,
with equivalent results. The chip can be powered up and
operated with SYNC grounded, but the input-to-output
latency may vary by 1/2 input sample period and the host
system won’t know which (even- or odd-numbered) CLK
rising edges strobe the input register. The setup and hold timing requirements for SYNC, with respect to the rising edges
of CLK, are the same as those for all other data and control
inputs except OE, which is asynchronous. In two-channel
mode, it must remain low after the first incoming data value.
0
0
1
01
Interpolate (0 dB)
* x/sinx
0
1
1
01
Interpolate1 (-6 dB)
* x/sinx
1
0
1
01
Decimate * x/sinx
1
1
1
01
Equal Rate LPF * x/sinx
0
0
1
10
Delay + Interpolate2
(0 dB)
0
1
1
10
Delay + Interpolate2
(0 dB) * x/sinx
1
0
1
10
Delay + Decimate2
1
1
1
10
Bypass (Delay Only)
0
0
1
11
2-Channel Interpolate3
(0 db)
0
1
1
11
2-Channel Interpolate3
* x/sinx
1
0
1
11
2-Channel Decimate3
1
1
1
11
Delay * x/sinx
When decimating, the user should likewise bring SYNC
HIGH for at least one clock cycle, returning it LOW when a
fresh output is desired. The chip will continue to update the
output register on alternate rising edges of CLK. The user
may leave SYNC LOW or change its value once per clock
cycle, with equivalent results. The chip can be powered up
and operated with SYNC grounded, but the host system
won’t know whether the data outputs are updated on even- or
odd-numbered system clock cycles. In any half-band decimating filter, a given single-cycle impulse’s arrival time (on
an odd versus an even clock cycle) determines whether it
generates a half-amplitude two-cycle impulse or a halfspeed, 40-clock, filtered output shaped by the nonzero, noncenter coefficients. The SYNC control permits the host system to obtain consistent results. In two-channel mode, it
must remain low after the first incoming data value.
When the result is rounded to fewer than 16 bits, the
unneeded lowest positions of the output bus are tristated
and become supplementary control bits, which enable the
x/sin(x) filter, bypass/delay, double-latency, dual-channel,
2
Note:
1. These modes limit to 15 bits (SO14-0) instead of 16
(SO15-0) and are provided for backward compatibility to
earlier parts.
2. These modes, which double the chip’s overall group delay
from 34 to 68 CLK cycles, can be used to equalize intercomponent delays where Y is sampled at twice the rate of
CB or CR (e.g. 4:2:2 and 8:4:4 formats).
3. These modes accommodate multiplexed two-channel data, e.g. CB/CR.
TMC2242C
PRODUCT SPECIFICATION
Table 2. Package Interconnections
Signal
Type
Name
Function
PLCC
Pin
MQFP
Pin
Timing
CLK
Clock
42
36
SYNC
Synchronization
43
37
SI11-0
Input Data Port
40,
37-30,
27-25
34,
31-24,
21-19
Data Out SO15-4 Output Data Port
4-11,
14-17
42-44,
1-5,
8-11
DualSO3-0
Function
Controls
INT
Output
Data; Controls
18-21
12-15
Interpolate
44
38
Data In
DEC
Decimate
1
39
RND2-0
Rounding
Position
22-24
16-18
TCO
Output Format
2
40
OE
Output Enable
3
41
The output data format is two’s complement if TCO is HIGH,
inverted or offset binary if LOW. Unless all 16 output bits are
used, the user can also select either signed or unsigned input
data, via pin SO0 (see pin description note 2, below). As
shown in pin description note 1, the output is half-LSB
rounded to the resolution selected by the value of RND2-0.
The asynchronous three-state output enable control simplifies
connection to a data bus with other drivers.
44 Lead PLCC
34
35
36
37
38
39
40
41
27
8
26
9
25
10
24
11
23
22
28
27
26
25
24
23
22
21
20
29
19
30
17
18
16
28
7
21
31
15
29
TMC2242C
6
20
32
30
5
19
33
14
31
4
18
13
3
17
34
32
16
TMC2242C
12
42
35
33
2
15
36
11
1
14
10
SO12
SO11
SO10
SO9
SO8
GND
VDD
SO7
SO6
SO5
SO4
43
37
13
9
GND
VDD
SI10
SI9
SI8
SI7
SI6
SI5
SI4
SI3
VDD
12
38
GND
VDD
SI10
SI9
SI8
SI7
SI6
SI5
SI4
SI3
VDD
65-2242C-02A
65-2242C-02B
SO3
SO2
SO1
SO0
RND2
RND1
RND0
SI0
SI1
SI2
GND
39
8
44
40
41
42
43
1
44
2
3
4
7
SO3
SO2
SO1
SO0
RND2
RND1
RND0
SI0
SI1
SI2
GND
SO12
SO11
SO10
SO9
SO8
GND
VDD
SO7
SO6
SO5
SO4
5
6
SO13
SO14
SO15
OE
TCO
DEC
INT
SYNC
CLK
GND
SI11
SO13
SO14
SO15
OE
TCO
DEC
INT
SYNC
CLK
GND
SI11
Pin Assignments
44 Lead MQFP
3
PRODUCT SPECIFICATION
TMC2242C
Pin Descriptions
Pin Number
Pin Name
PLCC
MQFP
Pin Function Description
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 on
every rising edge of CLK, although the output register is strobed on alternate
rising edges during decimation. In all modes, the frequency applied to CLK is the
higher of the input and output data sampling rates. During interpolation, the chip
reads its input bus on alternate rising edges of CLK.
SYNC
43
37
Synchronization. During interpolation, the chip accepts input data on alternate
rising edges of CLK and inserts zeroes on the remaining cycles. If SYNC is
HIGH during CLK rising edge 0 and LOW during CLK rising edge 1, the chip will
accept data on CLK 1 and insert a zero on CLK 2. Thereafter, if SYNC is either
held LOW or fed a square wave of half the CLK frequency, the part will continue
to accept data on odd-numbered CLK edges and to stuff zeroes on evennumbered edges. Similarly, during decimation, the output data change only on
alternate clock cycles. If the user operates SYNC as above, each evennumbered rising edge of CLK will trigger a change in the output. In all other
modes, the state of SYNC doesn’t affect operation of the chip.
Dedicated Data Input Port
SI11-0
40,
37-30,
27-25
34,
31-24,
21-19
Input Data. A 12-bit two’s complement or unsigned input word is registered by
the rising edges of CLK. SI0 is the LSB.
Dedicated Data Output Port
SO15-0
4-11,
14-21
42-44,
1-5,
8-15
Output Data MSBs. When OE is LOW, the 12 most significant bits of the filter’s
output emerge here, following each rising edge of CLK. The format may be two’s
complement, unsigned, or inverted offset binary. Bits SO15-4 correspond to
input bits SI11-0, respectively. An on-chip limiter prevents overflows and
underflows in the output data.
Dual Function Data Output/Control Input Pins
SO3-2
Output Data. These pins serve as data outputs when RND2 is LOW. When
RND2 is HIGH, they become additional filter mode controls (Table 1).
SO1
Output Data 2nd LSB. This pin is a data output when RND2-1 are LOW. When
either RND2 or RND1 is HIGH, it becomes an additional rounding control.1
SO0
Output Data LSB. This pin is a data output if and only if all RND bits are LOW.
Otherwise, it augments the data I/O format controls.2
Dedicated Static Controls (Set state before first desired data input.)
INT, DEC
44, 1
38, 39
Interpolate and Decimate. Jointly with SO3-2, these bits select the chip’s
overall operating mode, as discussed earlier in Table 1
TCO
2
40
Output format control. When TCO is HIGH, the output data are in two’s
complement format. When TCO is LOW, they are inverted offset binary, unless
SO0 is HIGH and RND is nonzero, in which case they are unsigned.
RND2-0
22-24
16-18
Round and output tristate. Selects output rounding position and active bus
width 8-16 bits. All outputs at and below the rounding bit position are tristated,
allowing the 4 LSBs to become control inputs.
Active, Asynchronous Control
OE
4
3
41
Output enable. LOW activates output bus from SO15 down to the effective LSB,
as chosen by RND2-0. All drivers at and below the rounding point are disabled,
as are all drivers when OE is HIGH.
PRODUCT SPECIFICATION
TMC2242C
Notes:
1. Rounding Operation Detail
2. I/O Format Operation Detail
RND
SO0
TCO
In Format
Out Format
0
Output
0
2’s Comp
Inverted
Offset
SO15-1 (15 bits)
0
Output
1
2’s Comp
2’s Comp
X
SO15-2 (14 bits)
>0
0
0
2’s Comp
011
X
SO15-3 (13)
Inverted
Offset
100
0
SO15-4 (12)
>0
0
1
2’s Comp
2’s Comp
100
1
SO15-8 (8)
>0
1
0
Unsigned
Unsigned
101
0
SO15-5 (11)
>0
1
1
Unsigned
2’s Comp
110
1
SO15-6 (10)
111
X
SO15-7 (9)
RND2-0
SO1
Output Rounding
000
OutputA
SO15-0 (16 bits)
001
OutputA
010
A. If RND2-0 = 00X, do not drive SO1, externally.
Absolute Maximum Ratings
(beyond which the device may be damaged)1
Parameter
Conditions
Supply Voltage
Min
Max
Units
-0.5
7.0
V
Input Voltage
-0.5
VDD + 0.5
V
Output Applied Voltage2
-0.5
VDD + 0.5
V
-3.0
+6.0
mA
1
sec
110
°C
140
°C
300
°C
150
°C
Externally Forced
Current3,4
Short Circuit Duration
Single output in HIGH state to ground
Operating Temperature (Case)
-20
Junction Temperature
Lead Soldering Temperature
Storage Temperature
10 seconds
-65
Notes:
1. Functional operation under any of these conditions is NOT implied. Performance and reliability are guaranteed only if Operating
Conditions are not exceeded.
2. Applied voltage must be current limited to specified range.
3. Forcing voltage must be limited to specified range.
4. Current is specified as conventional current flowing into the device.
5
PRODUCT SPECIFICATION
TMC2242C
Operating Conditions
Conditions
VDD
Power Supply Voltage
fCLK
Clock frequency
Min
Nom
Max
4.75
5.0
Units
5.25
V
TMC2242C
40
MHz
TMC2242C-1
60
MHz
tPWH
CLK pulse width, HIGH
6
ns
tPWL
CLK pulse width, LOW
6
ns
tS
Input Data Set-up Time
6
ns
tH
Input Data Hold Time
0
ns
VIH
Input Voltage, Logic HIGH
2.0
V
VIL
Input Voltage, Logic LOW
0.8
V
IOH
Output Current, Logic HIGH
-2.0
mA
IOL
Output Current, Logic LOW
4.0
mA
TA
Ambient Temperature, Still Air
70
°C
0
Electrical Characteristics
P arameter
IDD
Total Power Supply
Current
IDDU
IDDQ
Power Supply Current,
Unloaded
IOZL
IOS
Power Supply Current,
Quiescent
I/O Pin Capacitance
Input Current, HIGH
Input Current, HIGH
(Pulldown SO0–SO3)
Input Current, LOW
Leakage Current, HIGH
Leakage Current, HIGH
(Pulldown SO0–SO3)
Leakage Current, LOW
Short-Circuit Current
VOH
VOL
Output Voltage, HIGH
Output Voltage, LOW
CPIN
IIH
IIH
(PD)
IIL
IOZH
IOZH
(PD)
Conditions
Min
Typ
VDD = Max, CLOAD=25pF, fCLK=Max
TMC2242C
TMC2242C-1
VDD = Max, OE = HIGH, fCLK=Max
TMC2242C
TMC2242C-1
VDD = Max, CLK = LOW
Max
Units
150
220
mA
mA
135
200
5
mA
mA
mA
5
VDD = Max, VIN = VDD
VDD = Max, VIN = VDD
VDD = Max, VIN = 0 V
OE = HIGH, VOUT = VDD
OE = HIGH, VOUT = VDD
OE = HIGH, VOUT = 0 V
VDD = Max, Output = HIGH, one pin to
ground, one second duration max.
SO15-0, IOH = Max
SO15-0, IOL = Max
-90
pF
µA
µA
±10
-10
+150
±10
±10
-10
+150
±10
-150
µA
mA
0.4
V
V
2.4
µA
µA
µA
Switching Characteristics
Parameter
Output Delay Time
tDO
tHO
Output Hold Time
tENA
Output Enable Time
tDIS
Output Disable Time
6
Conditions
CLOAD = 25 pF
CLOAD = 25 pF
CLOAD = 0 pF
CLOAD = 0 pF
Min
Typ
Max
15
2.5
15
30
Units
ns
ns
ns
ns
PRODUCT SPECIFICATION
TMC2242C
Table 3a. Input Data Formats and Bit Weighting
Format
SI11
SI10
S9
...
SI1
S0
Two’s Comp.
-20
2-1
2-2
...
2-10
2-11
Unsigned
20
2-1
2-2
...
2-10
2-11
Table 3b. Output Data Formats and Bit Weighting
Format
SO15
SO14
SO13
...
SO5
SO4
-10
-2
2
2
...
2
2-11
Unsigned1
20
2-1
2-2
...
2-10
2-11
-6 dB t.c.2
-20
-20
2-1
...
2-9
2-10
0
20
2-1
...
2-9
2-10
Unsgn3
-1
-2
Two’s Comp.
-6 dB
0
Notes:
1. Inverted offset binary is the same as unsigned, except that all bits are complemented.
2. In -6 dB interpolation modes, the two’s complement sign bit is replicated in SI15 and SI14.
3. In -6 dB interpolation mode, the unsigned MSB is preceded by a 0 in SO15.
4. A leading minus sign denotes the two’s complement sign bit.
5. In all operating modes except “interpolate -6 dB,” dc gain is exactly unity.
Table 4. Rounded LSBs as a function of RND2-0
RND2-0
SO15
SO14
SO13
…
SO8
SO7
SO6
SO5
SO4
SO3
SO2
SO1
SO0r
000
SO15
SO14
SO13
…
SO8
SO7
SO6
SO5
SO4
SO3
SO2
SO1r
z
001
SO15
SO14
SO13
…
SO8
SO7
SO6
SO5
SO4
SO3
SO2r
z
z
010
SO15
SO14
SO13
…
SO8
SO7
SO6
SO5
SO4
SO3r
z
z
z
011
SO15
SO14
SO13
…
SO8
SO7
SO6
SO5
SO4r
z
z
z
z
1002
SO15
SO14
SO13
…
SO8
SO7
SO6
SO5r
z
z
z
z
z
101
SO15
SO14
SO13
…
SO8
SO7
SO6r
z
z
z
z
z
z
110
SO15
SO14
SO13
…
SO8
SO7r
z
z
z
z
z
z
z
111
Note:
1. The “r” indicates that the trailing significant output bit has been rounded to the nearest 1/2 LSB. All output drivers at and
below the rounding bit are disabled, allowing the lower output bits to be used as control inputs.
2. If SO1 = 1, format is 8 bits, viz: SO15…SO8r z…z.
Table 5. Steady-State Output Values and Limit Triggers
Input
Unsigned
Interpolate -6 dB
All Other Modes
Interpretation
2’s Comp.
Unsigned
2’s Comp.
Unsigned
2’s Comp.
3FF81
FFF01
7FF01
Unsigned
2’s Comp.
full-scale
full-scale +
3/4-scale
1/2 scale +
FFF
7FF
7FF81
C00
400
6000
2000
C000
4000
801
001
4008
0008
8010
0010
800
000
4000
0000
8000
0000
7FF
FFF
3FF8
FFF8
7FF0
FFF0
400
C00
2000
E000
4000
C000
1/4-scale
1/2-scale –
000
800
00001
C0001
00001
80001
zero
full-scale –
1 LSB +
1/2-scale
Zero
1 LSB –
Notes:
1. Full-scale values are minima and maxima permitted by on-chip limiter. Transient overshoots arising from large input signal
transitions will be clipped to these limits.
7
TMC2242C
PRODUCT SPECIFICATION
Performance Curves
0
-10
Response (dB)
-20
-30
-40
-50
65-2242C-03
-60
-70
-80
0.00
0.05
0.10
0.15
0.20
0.25
0.30
Normalized Frequency
0.35
0.40
0.45
0.50
Figure 1. Frequency Response
0.030
0.025
Response (dB)
0.020
0.015
0.010
0.006
65-32242C-04
0.000
-0.008
-0.010
0.00
0.05
0.10
0.15
0.20
0.35
Normalized Frequency
Figure 2. Passband Ripple Response
110
100
90
70
60
50
40
30
20
65-2242C-05
%/Full Scale
80
10
0
-10
0
10
20
30
Sample
40
50
60
Figure 3. Step Response
8
PRODUCT SPECIFICATION
TMC2242C
Equivalent Circuits
VDD
VDD
p
p
Digital
Input
Digital
Output
n
n
65-2242C-10
65-2242C-09
GND
GND
Figure 4. Equivalent Digital Input Circuit
Figure 5. Equivalent Digital Output Circuit
Timing Diagrams
tPWH
1/fC
tPWL
CLK
tS
34
SI11-0
tH
35
36
37
38
SYNC
tHO
tDO
1
SO15-0
2
3
4
65-2242C-06
OE is LOW.
Note: Values at SO15-0 are impulse response centers (peaks) corresponding to same-numbered inputs.
Figure 6. Equal Rate Mode
tPWH
1/fC
34
CLK
35
tS
SI11-0
34
36
tPWL
37
38
tH
35
36
37
38
SYNC
tHO
1
SO15-0
3
65-2242C-07
OE is LOW.
Figure 7. Decimate Mode
9
TMC2242C
PRODUCT SPECIFICATION
tPWH
1/fC
34
CLK
35
tS
36
37
38
tH
35
SI11-0
tPWL
37
SYNC
tHO
tDO
1
SO15-0
2
3
4
65-2242C-08
OE is LOW.
Figure 8. Interpolate Mode
tPWH
1/fC
68
CLK
69
tS
SI11-0
68
70
tPWL
71
72
tH
69
70
71
72
SYNC
tHO
1
SO15-0
3
65-2242C-14
OE is LOW.
Figure 9. Decimate Mode – Double Latency
tPWH
1/fC
68
CLK
69
tS
70
71
72
tH
69
SI11-0
tPWL
71
SYNC
tHO
1
SO15-0
tDO
2
3
4
65-2242C-15
OE is LOW.
Figure 10. Interpolate Mode – Double Latency
10
PRODUCT SPECIFICATION
TMC2242C
tPWH
1/fC
34
CLK
SI11-0
Y
35
67
tS
tH
C
68
1
Y
36
Y
tPWL
37
69
38
70
C
Y
71
SYNC*
tHO
SO15-0
2
C
5
65-2242C-16
OE is LOW.
*In two-channel modes, sync must be left low after the first data input.
Figure 11. Decimate Mode – Two-Channel
tPWH
1/fC
34
CLK
35
tS
36
tPWL
37
38
tH
69
SI11-0
Y
71
C
SYNC*
tHO
1
SO15-0
tDO
Y
C
Y
3
*In two-channel modes, sync must be left low after the first data input.
Figure 12. Interpolate Mode – Two-Channel
tENA
tDIS
0.5V
Three-State
Outputs
2.0V
0.8V
0.5V
High Impedance
65-2242C-11
Figure 13. Threshold Levels for Three State Measurements
11
C
65-2242C-17
OE is LOW.
OE
Y
PRODUCT SPECIFICATION
TMC2242C
Applications Discussion
In Figure 15, the TMC2242C drives a fast D/A converter to
reconstruct analog composite video. The TMC3003 10-bit
digital-to-analog converter inputs, D9-0 are connected to the
TMC2242C outputs SO15-6, respectively. The TMC2242C
RND2-0 controls are set to 110 for rounded 10-bit interpolation operation.
The TMC2242C is well-suited to filtering digitized composite or component NTSC or PAL video. In Figure 14, the
TMC1175A 8-bit video A/D converter outputs, D7-0, are
connected to the TMC2242C inputs, SI11-4, respectively. To
minimize noise and any chance of electrostatic damage,
inputs SI3-0 should be grounded. Controls RND2-0 are set to
100 and SO1 is forced high to effect 8-bit rounding. SO3-2,
TCO, and DEC are forced low, whereas INT and SO0 are
forced high. (Setting SO0 high and TCO low selects
unsigned binary format at the input and output data ports,
eliminating the need for external MSB inverters.)
TTL Clock
27.000 MHz (D1)
28.636 MHz (NTSC D2)
2 uH
Composite
Video
75 Ohm
300 pF
2 uH
VIN
510 pF
300 pF
TMC1175A
8-bit A/D
75 Ohm
TMC2242C
D7-0
AGND
SI11-4
8
SO15-8
27.000 MHz (D1)
28.636 MHz (NTSC D2)
65-2242C-12
8
13.500 MHz (D1)
14.318 MHz (NTSC D2)
Figure 12. Decimating Oversampled Video With a Low Cost 8-bit A/D
TCO = 0 RND = 100 SO(3:0) = 0011 DEC = 0 INT = 1
TTL Clock
27.000 MHz (D1)
28.636 MHz (NTSC D2)
TMC3003
TMC2242C
2 uH
10-bit D/A
12
SI11-0
SO15-6
10
D9-0
IOUT
75 Ohm
AGND
13.500 MHz (D1)
14.318 MHz (NTSC D2)
510 pF
300 pF
27.000 MHz (D1)
28.636 MHz (NTSC D2)
Note: Data buses are unsigned binary.
Figure 13. Interpolating Digital Video Signals before Reconstruction
TCO = 0 RND = 110 SO(3:0) = 0011 DEC = 0 INT = 0
12
2 uH
300 pF
Composite
Video
75 Ohm
65-2242C-13
TMC2242C
PRODUCT SPECIFICATION
Notes:
13
PRODUCT SPECIFICATION
TMC2242C
Mechanical Dimensions – 44-Pin PLCC Package
Inches
mbol
Min.
Max.
Min.
Max.
.165
.090
.020
.013
.026
.180
.120
—
.021
.032
4.19
2.29
.51
.33
.66
4.57
3.05
—
.53
.81
.685
.695
.650
.656
.500 BSC
.050 BSC
.042
.056
11
44
—
.004
E1
E3
/NE
Millimeters
17.40
17.65
16.51
16.66
12.7 BSC
1.27 BSC
1.07
1.42
11
44
—
0.10
Notes:
Notes
1. All dimensions and tolerances conform to ANSI Y14.5M-1982
2. Corner and edge chamfer (J) = 45°
3. Dimension D1 and E1 do not include mold protrusion. Allowable
protrusion is .101" (.25mm)
3
2
E
E1
D
J
D1
D3/E3
B1
J
e
A1
A2
B
–C–
LEAD COPLANARITY
ccc C
14
TMC2242C
PRODUCT SPECIFICATION
Mechanical Dimensions – 44-Lead MQFP Package
Inches
Symbol
Min.
A
A1
A2
B
C
D/E
D1/E1
e
L
N
ND
α
ccc
Max.
.077
.093
.000
.010
.077
.083
.012
.018
.005
.009
.510
.530
.390
.398
.032 BSC
.026
.037
44
11
0°
7°
—
.004
Millimeters
Min.
Notes:
Notes
1. All dimensions and tolerances conform to ANSI Y14.5M-1982.
Max.
1.95
2.35
.00
.25
1.95
2.11
.30
.46
.13
.23
12.95
13.45
9.90
10.10
.81 BSC
.66
.94
44
11
0°
7°
—
0.10
2. Dimensions "D1" and "E1" do not include mold protrusion.
3. Pin 1 identifier is optional.
4. Dimension N: number of terminals.
5. Dimension ND: Number of terminals per package edge.
7
6. "L" is the length of terminal for soldering to a substrate.
7. "B" includes lead finish thickness.
2
6
4
5
D
D1
e
PIN 1
IDENTIFIER
E E1
C
L
α
0.063" Ref (1.60mm)
See Lead Detail
A
Base Plane
A2
B
A1
Seating Plane
-CLEAD COPLANARITY
ccc
C
15
TMC2242C
PRODUCT SPECIFICATION
Ordering Information
Product Number
Temperature
Range
Speed
Grade
Screening
Package
Package Marking
TMC2242CR2C
0°C to 70°C
40 MHz
Commercial
44-Lead PLCC
2242CR2C
TMC2242CR2C1
0°C to 70°C
60 MHz
Commercial
44-Lead PLCC
2242CR2C1
TMC2242CKTC
0°C to 70°C
40 MHz
Commercial
44-Lead MQFP
2242CKTC
TMC2242CKTC1
0°C to 70°C
60 MHz
Commercial
44-Lead MQFP
2242CKTC1
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER
DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES
OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body,
or (b) support or sustain life, or (c) whose failure to perform
when properly used in accordance with instructions for use
provided in the labeling, can be reasonably expected to
result in significant injury to the user.
2. 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, or to affect its safety or effectiveness.
www.fairchildsemi.com
6/1/99 0.0m 004
Stock#DS7002242C
 1998 Fairchild Semiconductor Corporation