PTN3700
1.8 V simple mobile interface link bridge IC
Rev. 01 — 14 August 2007
Product data sheet
1. General description
The PTN3700 is a 1.8 V simple mobile interface link bridge IC which can function both as
a transmitter-serializer or a receiver-deserializer for RGB888 video data. When configured
as transmitter (using input pin TX/RX), the PTN3700 serializes parallel CMOS video input
data into 1, 2 or 3 subLVDS-based high-speed serial data channels. When configured as
receiver, the PTN3700 deserializes up to 3 high-speed serial data channels into parallel
CMOS video data signals.
The parallel interface of the PTN3700 is based on the conventional and widely used 24-bit
wide data bus for RGB video data, plus active LOW HS (Horizontal Synchronization) and
VS (Vertical Synchronization) signals, and an active HIGH DE (Data Enable) signal. An
additional two auxiliary bits A[1:0] are provided to permit signaling of miscellaneous status
or mode information across the link to the display. The serial interface link of the PTN3700
is based on the open Simple Mobile Interface Link (SMILi) definition. In order to keep
power low while accommodating various display sizes (e.g., up to 24-bit, 60 frames per
second XVGA), the number of high-speed serial channels (‘lanes’) is configurable from
1 to 3 depending on the bandwidth needed. The data link speed is determined by the
PCLK (Pixel Clock) rate and the number of serial channels selected.
In order to maintain a low power profile, the PTN3700 has three power modes,
determined by detection of an active input clock and by shutdown pin XSD. In Shutdown
mode (XSD = LOW), the PTN3700 is completely inactive and consumes a minimum of
current. In Standby mode (XSD = HIGH), the device is ready to switch to Active mode as
soon as an active input clock signal is detected, and assume normal link operation.
In Transmitter mode, the PTN3700 performs parity calculation on the input data (R[7:0],
G[7:0], B[7:0] plus HS, VS and DE data bits) and adds an odd parity bit CP to the serial
transmitted data stream. The PTN3700 in Receiver mode also integrates a parity
checking function, which checks for odd parity across the decoded input word (R[7:0],
G[7:0], B[7:0] plus HS, VS and DE data bits), and indicates whether a parity error has
occurred on its CPO out pin (active HIGH). When a parity error occurs, the most recent
error-free pixel data will be output instead of the received invalid pixel data.
PTN3700 in Receiver mode offers an optional advanced frame mixing feature, which
allows 18-bit displays to effectively display 24-bit color resolution by applying a
patent-pending pixel data processing algorithm to the 24-bit video input data.
One of two serial transmission methods is selectable: pseudo source synchronous
transmission based on the pixel clock, or true source synchronous transmission based on
the bit clock. The latter uses a patent-pending methodology characterized by zero
overhead and operation guaranteed free from false pixel synchronization.