Multimedia ICs Color TV signal encoder BH7240AKV The BH7240AKV is an IC that converts digital RGB signals (8-bit) to NTSC and PAL color TV signals. In addition to composite output, luminance output, chrominance output, and analog RGB output are available. Each type of output is equipped with an internal 75Ω driver. •TVApplications peripheral devices •1)Features Supports both NTSC and PAL. 4) Y / C separation output pin. 5) Analog RGB signal output pin. 3) Internal 75Ω driver. 2) Internal RGB3-channel DAC (internal regulator). 3) Internal burst timing generator circuit. BDATA4 BDATA5 BDATA6 BDATA7 GDATA0 GDATA1 GDATA2 GDATA3 GDATA4 GDATA5 GDATA6 GDATA7 •Block diagram 36 35 34 33 32 31 30 29 28 27 26 25 8 BDATA3 37 DECODER DECODER DECODER BDATA2 38 BDATA1 39 BDATA0 40 VCLK 41 CLK DGND 42 VREFOUT 43 VREF LATCH CLK CLK LATCH CELL MATRIX CELL MATRIX CELL MATRIX CLAMP CLAMP CLAMP VCC CLK GND Burst Flag GEN. R-Y 44 R G AGND1 45 B SYNC B-Y SYNC ADD. LPF RDATA2 21 RDATA3 20 DVDD 19 RDATA4 18 RDATA5 17 RDATA6 16 RDATA7 15 SCIN 14 SYNCIN 13 NT / PAL VCC 1 2 3 4 5 6 7 8 9 10 11 12 N.C. 75 N.C. 75 YTRAP 75 VCC2 75 VOUT 75 SYNC COUT 75 Y/C MIX BPF YOUT 6dB BOUT GND 6dB GOUT 48 6dB ROUT GCLAMP VCC 6dB GND2 47 22 YTRAP 46 VCC1 RDATA1 SYNC BCLAMP RCLAMP 23 CHROMA GEN. Y GND RDATA0 LATCH MATRIX N.C. 24 8 8 1 Multimedia ICs BH7240AKV •Absolute maximum ratings (Ta = 25°C) Parameter Power supply voltage Power dissipation Symbol Limits Unit DVDD, AVCC1 AVCC2 7∗1 V Pd 900∗2 mW Operating temperature Topr – 20 ~ + 70 °C Storage temperature Tstg – 55 ~ + 125 °C ∗1 At Ta = 25°C ∗2 Reduced by 9.0mW for each increase in Ta of 1°C over 25°C. (When mounted on a 70mm × 70mm × 1.6mm glass epoxy board.) •Recommended operating conditions (Ta = 25°C) Parameter Power supply voltage Symbol Limits Unit DVDD, AVCC1 AVCC2 4.50 ~ 5.50 V •Recommended input conditions (at DV DD Parameter 2 = AVCC1 = AVCC2 = 5.0V) Symbol Limits Unit VCLK, RGBDATA input high level VTH 2.2 ~ 5.0 V VCLK, RGBDATA input low level VTL GND ~ 0.8 V SYNCIN, NT / PAL input high level VTH 2.2 ~ 5.0 V SYNCIN, NT / PAL input low level VTL GND ~ 0.8 V Multimedia ICs BH7240AKV •Pin descriptions Pin No. Pin name 1 BCLAMP 2 AGND2 3 ROUT 4 GOUT Analog green signal output. Internal 75Ω driver 5 BOUT Analog blue output. Internal 75Ω driver 6 YOUT Luminance signal output. Internal 75Ω driver 7 COUT Chrominance signal output. Internal 75Ω driver 8 VOUT Composite video signal output. Internal 75Ω driver 9 AVCC2 10 YTRAP 11 Function Analog blue signal clamping pin GND pin for 75Ω driver Analog red signal output. Internal 75Ω driver N.C. Power supply pin for 75Ω driver Luminance trap filter connection pin. Connecting a trap filter eliminates the chrominance band component included in the luminance signal, and reduces the amount of chrominance color. Output impedance is approximately 2kΩ. This is effective only for composite video output. This pin is not connected within the IC. 12 N.C. This pin is not connected within the IC. 13 NT / PAL 14 SYNCIN 15 SCIN 16 RDATA7 Red data input pin (bit 7) 17 RDATA6 Red data input pin (bit 6) 18 RDATA5 Red data input pin (bit 5) 19 RDATA4 Red data input pin (bit 4) 20 DVDD 21 22 RDATA3 RDATA2 Red data input pin (bit 3) Red data input pin (bit 2) 23 RDATA1 Red data input pin (bit 1) 24 RDATA0 Red data input pin (bit 0) 25 GDATA7 Green data input pin (bit 7) 26 GDATA6 Green data input pin (bit 6) 27 GDATA5 Green data input pin (bit 5) 28 29 GDATA4 GDATA3 Green data input pin (bit 4) Green data input pin (bit 3) 30 GDATA2 Green data input pin (bit 2) 31 GDATA1 Green data input pin (bit 1) 32 GDATA0 Green data input pin (bit 0) 33 BDATA7 Blue data input pin (bit 7) 34 BDATA6 Blue data input pin (bit 6) 35 BDATA5 Blue data input pin (bit 5) 36 BDATA4 Blue data input pin (bit 4) 37 BDATA3 Blue data input pin (bit 3) 38 BDATA2 Blue data input pin (bit 2) 39 BDATA1 Blue data input pin (bit 1) Video output method selector pin. NTSC when HIGH, PAL when LOW Composite SYNC input. For LOW input, SYNC is output to YOUT and VOUT. At the same time, DC clamping of the RGB signal takes place. Color subcarrier input. Sine waves of a frequency corresponding to the required output method, or pulse waves with a duty of 50%, should be input in a range not exceeding VCC-GND. Power supply pin for digital circuit 3 Multimedia ICs Pin No. Pin name 40 BDATA0 41 VCLK 42 DGND 43 4 BH7240AKV VREFOUT 44 N.C. 45 AGND1 46 RCLAMP 47 VCC1 48 GCLAMP Function Blue data input pin (bit 0) System clock input. RGB data is taken into the IC at the timing of this clock. GND pin for digital circuit RGB DAC reference voltage output pin. A 0.1µF capacitor should be connected between the GND pins. This pin is not connected internally in the IC. GND pin for analog circuits (other than 75Ω driver) Analog red signal clamping pin Power supply pin for analog circuits (other than 75Ω driver) Analog green signal clamping pin Multimedia ICs BH7240AKV •Pin equivalent circuits Pin No. Pin name 1 BCLAMP 46 RCLAMP 48 GCLAMP 10 YTRAP Equivalent circuit 30 30 2k 50k (13pin) 100k (14pin) 13 NT / RAL 14 SYNCIN 15 SCIN 1k 1k 25k 20k 5 Multimedia ICs Pin No. Pin name BH7240AKV Equivalent circuit 3.2k 43 30 VREFOUT 4.8k 3 ROUT 4 GOUT 5 BOUT 6 YOUT 7 COUT 8 VOUT 16 ~ 19 RDATA7 ~ 4 21 ~ 24 RDATA3 ~ 0 25 ~ 32 GDATA7 ~ 0 33 ~ 40 BDATA7 ~ 0 41 6 VCLK 50 5k Multimedia ICs BH7240AKV •Electrical characteristics (unless otherwise noted, Ta = 25°C, DV DD Parameter = AVCC1 = AVCC2 = 5.0V) Symbol Min. Typ. Max. Unit ICC — 85 105 mA RGBDATA = 00 input VLWHITE 0.59 0.70 0.81 VP- P RGBDATA = FF input VLRED 0.18 0.21 0.24 VP- P RDATA = FF input VLGREEN 0.35 0.41 0.47 VP- P GDATA = FF input VLBLUE 0.07 0.08 0.09 VP- P BDATA = FF input Current consumption Conditions 〈Luminance level〉 (VOUT, YOUT) White level Red level Green level Blue level Sync level VLSYNC 0.27 0.30 0.33 VP- P — Sync / white level ratio RS / W 0.37 0.43 0.49 — — 〈Chrominance level〉 (VOUT, COUT) Red / Burst level ratio RR / BU 2.69 3.16 3.63 — RDATA = FF input Green / Burst level ratio R G / BU 2.51 2.95 3.39 — GDATA = FF input Blue / Burst level ratio RB / BU 1.91 2.24 2.57 — BDATA = FF input Burst level VCBURST 0.25 0.29 0.33 VP- P — θRED 94 104 114 deg RDATA = FF input θGREEN 231 241 251 deg GDATA = FF input θBLUE 337 347 357 deg BDATA = FF input ROUT output level VROUT 0.56 0.70 0.81 VP- P RDATA = FF input GOUT output level VGOUT 0.59 0.70 0.81 VP- P GDATA = FF input BOUT output level VBOUT 0.59 0.70 0.81 VP- P BDATA = FF input fDA — — 20 MHz — RGB DATA setup time TSET 20 — — ns — RGB DATA hold time THOLD 20 — — ns — SYNCIN, NT / PAL input high level current IH — — 300 µA When 5V is applied to pin SYNCIN, NT / PAL output low level current IL — — 200 µA When 0V is applied to pin Red phase Green phase Blue phase 〈RGB level〉 (ROUT, GOUT, BOUT) 〈Other〉 RGB DATA conversion frequency 7 Multimedia ICs BH7240AKV •Measurement circuit 8bit Digital blue signal 36 8bit Digital blue signal Clock 35 8bit Digital green signal 34 33 32 31 30 29 28 27 26 25 37 24 38 23 39 22 40 21 41 20 8bit Digital red signal VCC 19 42 BH7240AKV 43 18 44 17 45 16 46 15 Color sub carrier 47 14 Composite SYNC 48 13 8bit Digital red signal 0.1µF 0.1µF VCC 0.1µF 0.8V 1 2 3 4 75 75 + 220µ 6 75 GOUT 7 75 + + 220µ 220µ ROUT 8 5 75 + YOUT 9 10 11 12 75 + 220µ 0.047µ BOUT 8 + 220µ COUT VOUT VCC 0.8V 2.2V 2.2V Multimedia ICs BH7240AKV operation •(1)Circuit The DAC system clock is input to the VCLK pin. RGB data is taken into the IC at the rising edge of this clock. RGBDATA 0 1 2 3 4 5 VCLK Internal RGB 0 1 (2) The subcarrier is input to the SCIN pin. There is an internal input capacitor in the IC, so no external DC cutoff is necessary. Also, the input level supports a range of 0.5 to 5Vp-p. To avoid offset in the chrominance phase, distortion-free sine waves or pulses with a duty of 50% should be input in a range which does not exceed the VCC and GND. (3) Composite SYNC signals are input to SYNCIN. When the input level is low, SYNC signals are output to the composite output (V OUT) and luminance output (YOUT), and DC clamping of the RGB signals from the DAC is carried out at this timing. To prevent erroneous clamping, RGB data should be set to 00 input during the SYNC interval. (4) Burst timing and the chrominance phase reversal timing when PAL is used are generated by SYNC signals and subcarriers. For this reason, signals input as SYNC signals and subcarriers should be in conformance with standards. 2 3 4 5 (5) The NT / PAL pin is used to select the video output system. When the input level is high, NTSC is selected, and when the input level is low, PAL is selected. When PAL is selected, the chrominance phase is reversed once every hour. (6) A trap filter is connected to the YTRAP pin. This eliminates the chrominance band component that includes the luminance signal, and reduces crosscolor. This filter is effective only for composite output (VOUT), and does not affect luminance output (YOUT). (7) Composite signals are output from the VOUT pin. An internal 75Ω driver enables direct drive of the 75Ω load. (However, DC cutoff is required.) (8) Luminance signals and chrominance signals are output from the YOUT and COUT pins, respectively. An internal 75Ω driver enables direct drive of the 75Ω load. (However, DC cutoff is required.) (9) Analog RGB signals are output from R OUT, GOUT, and BOUT. An internal 75Ω driver enables direct drive of the 75Ω load. (However, DC cutoff is required.) •External dimensions (Units: mm) 9.0 ± 0.3 7.0 ± 0.2 24 48 13 1 1.425 ± 0.1 0.10 25 0.5 12 0.5 7.0 ± 0.2 9.0 ± 0.3 36 37 0.125 ± 0.1 0.2 ± 0.1 0.10 VQFP48 9