mc44251 Freescale Semiconductor, Inc, mc44251 Datasheet
mc44251
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mc44251 Summary of contents
Page 1
... The MC44251 also contains a dithering generator for video processing performance enhancements. The MC44251 is especially suitable as a front–end converter in TV–picture digital processing (picture–in–picture, frame storage, etc.). The high speed conversion rate of the ADC is suitable for video bandwidth of well over 6 MHz. ...
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... See Figure 11 V max See Figure 11 V range See Figure 11 Gain See Figure 11 (Note 1) DNL Differential Nonlinearity (Note 1) INL Integral Nonlinearity (Note 1) E gain Gain Difference (Note 2) E off Offset Difference (Notes 1, 2) MC44251 2 PIN ASSIGNMENTS bias SS( ...
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... — 2.0 A — 2 — ns Min Max Unit 3.5 — V — 1.5 V — 2.0 A Min Max Unit 2.0 5.0 A – 5.0 – 2.0 A — 0.5 A — 1.5 LSB Min Max Unit 130 70 130 Min Max Unit 0 0.8 V 4.2 V DD( 2.8 V — — — MC44251 3 ...
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... Clock Input 18 R4 Output Red, Bit Output Red, Bit Output Red, Bit Output Red, Bit 7 (MSB SS( Analog MC44251 4 Characteristic t f 90% 50% 10 QLH , t QHL 50% Figure 1. Clock and Output Timing PIN DESCRIPTIONS Pin No. Name 23 HZ ...
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... The value of the de- coupling capacitor should not exceed 47 nF. Large capac- itance values can cause problems because of the amount of energy stored. When a system containing the MC44251 is rapidly powered down and up, the capacitor voltage may exceed the supply voltage during the power up and cause a latch– ...
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... CIRCUIT OPERATION on–chip dc restoration circuit samples and adjusts the aver- age dc level of the input signal. The MC44251 has three selectable clamping levels for ac coupling. The clamp levels are selected by the MODE pin according to Table 1. In the RGB mode, the clamping levels are set to 16/256, corre- sponding to 6 ...
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... I I sink I source MC44251 clamp N PERIODS HZ MOTOROLA Figure 3a. Operation V 0 – V clamp = sink > V clamp source < V clamp t L Figure 3b. Power Up Figure 3. Clamp Network Timing Diagrams MC44251 7 ...
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... Since the video is processed as three 8–bit signals, the maximum number of different luminance levels is reduced to 256. In cases where only a 7–bit luminance signal is used, the maximum number EXPECTED ACTUAL Figure 5. Distortion Produced by Digitizing MC44251 VIDEO Figure 4. Horizontal Timing of luminance levels is reduced to 128 ...
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... V HZ 0.75 LSB 0 DITHER – 0.75 LSB MOTOROLA ANALOG SIGNAL + DITHER t Figure 6. Amplitude Dithering Figure 7. Effect of Dithering Pattern Figure 8. Dithering Sequence ANALOG SIGNAL COMPARATOR LEVEL 0.5 LSB 0.5 LSB 0.5 LSB MC44251 9 ...
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... RESTRICTIONS ON V DD(R) The normal operating condition for the MC44251 is defined as V DD( DD( DD(D) and the safe operating range of V DD(R) is defined DD(R where V DD(R) is operated at values other than should be noted that the accuracy of the conversion process is re- duced. In all cases V DD(R) should not be allowed to exceed V DD ...
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... V offset : V offset = b – V min code + (n+5) MID–POINT VOLTAGE n n+1 n+2 n+3 n+4 n+5 n+6 Figure 10. Integral Nonlinearity and Offset 1/GAIN = SLOPE V max V range Figure 11 · ( (n) in LSB SSI LEAST SQUARE FIT LINE OUTPUT CODE DC INPUT VOLTAGE MC44251 11 ...
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... PCB DESIGN To maximize the performance of the MC44251, noise should be kept to a minimum. Good printed circuit board de- sign will enhance the operation of the MC44251. Separate analog and digital grounds will reduce noise and conversion errors. In addition, separate filters on analog V CC and digital V DD will also help to minimize noise and conversion errors ...
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... SW1 is set either to position ‘1’ the open position depending on the desired clamp level (see Table 1). The RGB inputs then become YUV inputs and correspondingly, the RGB outputs are YUV. For RGB operation, SW1 is set to the ‘0’ position. MC44251 13 ...
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... WRONG FERRITE BEAD POWER CUT 0.1 F DECOUPLING MC44251 14 BETTER Figure 12. FERRITE BEAD LOW PASS FILTER FERRITE BEAD CUT Figure 13. INPUT OR OUTPUT SIGNAL GROUND MOTOROLA ...
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... V DD(A) MODE SS( DD(D) MOTOROLA V SS( CLK V SS( DD(D) Figure 14. Application Circuit MC44251 15 ...
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... DIMENSION H DOES NOT INCLUDE DAMBAR PROTRUSION OR INTRUSION. THE DAMBAR PROTRUSION(S) SHALL NOT CAUSE THE H DIMENSION TO BE GREATER THAN 0.037 (0.940). THE DAMBAR INTRUSION(S) SHALL NOT CAUSE THE H DIMENSION TO BE SMALLER THAN 0.025 (0.635). MC44251 16 PACKAGE DIMENSIONS FN SUFFIX CASE 777–02 0.007(0.180) B ...
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... N 0.13 0.17 0.005 0.007 0.13 0.30 0.005 0.012 S 12.95 13.45 0.510 0.530 T 0.13 ––– 0.005 ––– ––– 0 ––– V 12.95 13.45 0.510 0.530 W 0.40 ––– 0.016 ––– X 1.6 REF 0.063 REF MC44251 17 ...
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... Motorola, Inc. Motorola, Inc Equal JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center, 3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–81–3521–8315 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 *MC44251/D* MC44251/D MOTOROLA ...