Overview

The LC74401E, LC74402, and LC74402E are memory controllers for TV set and VCR PIP (picture in picture) systems. Since these LSIs include three D/A converter circuits, a component PIP system can be constructed by combining one of these LSIs with memory and an A/D converter such as the LC7480.

Features

• Horizontal resolution: 600 TV lines*1

• Three D/A converters (for the Y, R-Y, and B-Y signals) are incorporated in the PIP memory controller block.

• High image quality is supported by vertical filter function frame memory processing*2.

• I2C bus controlled.

• Built-in PLL circuit (requires an external LPF)

• Supports NTSC, PAL, and multiple (NTSC-PAL) formats

• External control functions (only provided by the LC74401E)

— 8-bit D/A converter (PWM): Six pins

— General-purpose ports: Four pins

• Sub-screen specifications

— Number of sub-screens: 1-8*2

— Display on/off and frame on/off/color switching, wipe function

— Supports switching between fixed (4 corners) and arbitrary (8-bit specification of vertical and horizontal position) display positions.

— Size: Area: 1/4, 1/9, 1/16, Vertical compression: 1/2, 1/3, 1/4; Horizontal compression: 2/3, 1/3, 1/6

Note: Horizontal compression can be adjusted by changing the PLL divisor. The display area can be changed independently in the vertical and horizontal directions.

— Horizontal resolution (Y signal): About 250 dots

— Gradation (quantization): 64 (6 bits)

• Operating supply voltage: 5 V ± 10

• QFP80E: LC74401E

• DIP64S: LC74402-Pin assignment identical to the LC7442 (except for the serial control pins)

• QFP64E: LC74402E-Pin assignment identical to the LC7442E (except for the serial control pins)