Compare DS90C385A with SN75LVDS83B

Hi Di,

Functionally, both parts are equivalents in that they are both serializers that translate 24-bit color + 3 control bit LVCMOS inputs to 4 LVDS serialized pairs. The pinout for the DGG package are pin-to-pin compatible.

The main differences I’m noticing is the operating range and the presence of IOVCC on the SN75LVDS83B (1.8 V to 3.3 V).

SN75LVDS83B: Operating Range is 10 MHz to 135 MHz, with selectable IOVCC.

DS90C385A:  Operating Range is 18 MHz to 87.5 MHz with fixed I/O voltage swing of 3.3 V.

The SN75LVDS83B looks like a slightly more versatile part, because it can operate at a much larger clock and has a selectable I/O supply reference voltage to match the GPU data output signal swing.

As a general note for these LVDS SerDes parts, one of the key performance specs for SerDes parts in an application standpoint is the receive skew margin (RSKM). This parameter is usually seen on the receiver part's datasheet, but the calculation of the RSKM is determined by a combination of the Transmitter Pulse Position (Tppos) and the Receiver Strobe Position (Rspos). In this way, the transmitter minimum and maximum pulse positions are important parameters to assess when choosing the right transmitter such that you do not need to worry about the Tx pulse position overlapping with the corresponding Rx strobe position. The larger the margin, the better, as this parameter illustrates the minimum amount of time difference between the maximum transmit pulse position and the subsequent minimum receive strobe position.

Thanks,

Michael