Features: · 4Mbits (512k x 8 bits) organization FIFO
· Independent 8bit read/write port operations (different read/write data rates acceptable)
· Maximum Read/write cycle time: 80Mhz and 40Mhz (2 speed grades)
· Input Enable (write mask) / Output Enable (data skipping) control
· Window read/write with Mirroring capable
· Selectable control signal polarity
· Input Ready / Output Ready flags
· Direct cascade connection
· Self refresh
· 3.3V ± 10% power supply
· Standard 44-pin TSOP (II) packageApplication· Multimedia systems
· Video capture or editing systems forNTSC/PAL or SVGA resolution
· Security systems
· Scan rate converters
· PIP (Picture-In-Picture) video display
· TBC (Time Base Correction)
· Frame synchronizer
· Digital video camera
· Hard disk cache memory
· Buffer for communication systems
* 80MHz Hiigh-Speed versiion
· DTV/HDTV video stream bufferPinoutDescriptionThe AL440B is a high-performance FIFO (First-In-First-Out) field memory chip designed to buffer audio/video/graphic digital data for a wide range of applications.
The AL440B FIFO memory provides completely independent 8bit input and output ports that can operate at a maximum speed of 80 MHz. The built-in address and pointer control circuits provide a straightforward bus interface to serially read/write memory that can reduce inter-chip design efforts. Manufactured using a state-of-the-art embedded high density memory cell array, the AL440B uses high performance process technologies with extended controller functions (write mask, read skip, window mode read/write .. etc.), allowing easy operation of non-linearity and regional read/write FIFO for PIP, Digital TV, security system and video camera applications.
The 4Mbits AL440B is configured as 512k x 8-bit FIFO to accommodate NTSC, PAL or up to SVGA resolution. Running at high speed (80 MHz maximum) and low power consumption AC characteristics (3.3V power supply) allow the high performance and high quality application capability for designs such as HDTV.
Additional manipulation is produced by the Input/Output Enable control signals. The application of AL440B can use input enable to control whether new data is going to be written over the old data or not. For read data, the output enable signal can control whether data is going to be skipped during the read operation.
The Input/Output Ready flags report the FIFO status. The flags can be used to indicate Fullness/Emptiness of the FIFO capacity. Expanding AL440B data bus width is also possible by using multiple AL440B chips in parallel.
To have better control flexibility in the inter-chip design, the polarities of the AL440B control signals are selectable. The read and write ports control signals, such as Read/Write Enable, Input/Output Enable.., can be either active low or high by pulling /PLRTY signal to high or low respectively.
Window data read/write is supported in the AL440B to benefit the designing effort for applications such as PIP display. The window mode is enabled by driving low on /SDAEN signal. A serial bus can program built-in registers to set up coordinates of the window and the settings take effect following by next read/write reset pulse. Window mirroring can cooperate with the window mode data access to flip window data in x or y direction. When window-mirroring function is turned on, write data can be stored in reverse sequence.
AL440B is available as a 44-pin TSOP (II), the small footprint allows product designers to keep real estate to a minimum.