DS90UB940-Q1 Datasheet, PDF (36/84 Pages) Texas Instruments – FPD-Link III to CSI-2 Deserializer

DS90UB940-Q1
SNLS479A – NOVEMBER 2014 – REVISED JANUARY 2016
www.ti.com
8.4 Device Functional Modes
8.4.1 Configuration Select
The DS90UB940-Q1 can be configured for several different operating modes via the MODE_SEL[1:0] input pins,
or via the register bits 0x23 [4:3] (MODE_SEL1) and 0x6A [5:4] (MODE_SEL0) . A pull-up resistor and a pull-
down resistor of suggested values may be used to set the voltage ratio of the MODE_SEL[1:0] input and VDD33
to select one of the possible selected modes.
The DS90UB940-Q1 is capable of operating in either in 1-lane or 2-lane modes for FPD-Link III. By default, the
FPD-Link III receiver automatically configures the input based on 1- or 2-lane mode operation. Programming
register 0x34 [4:3] settings will override the automatic detection. For each FPD-Link III pair, the serial datastream
is composed of a 35-bit symbol.
The DS90UB940-Q1 recovers the FPD-Link III serial datastream(s) and produces CSI-2 TX data driven to the
MIPI DPHY interface. There are two CSI-2 ports (CSI0_Dn and CSI1_Dn) and each consist of one clock lane
and four data lanes. The DS90UB940-Q1 supports two CSI-2 TX ports, and each may be configured to support
either two or four CSI-2 data lanes. Unused CSI-2 outputs are driven to LP11 states. The MIPI DPHY
transmission operates in both differential (HS) and single-ended (LP) modes. During HS transmission, the pair of
outputs operates in differential mode; and in LP mode, the pair operates as two independent single-ended traces.
Both the data and clock lanes enter LP mode during the horizontal and vertical blanking periods.
The configurations outlined in (1-lane FPD-Link III Input, 4 MIPI lanes Output, 1-lane FPD-Link III Input, 2 MIPI
lanes Output, 1- or 2-lane FPD-Link III Input, 2 or 4 MIPI lanes Output in Replicate) will apply to DS90UB949-Q1,
DS90UB947-Q1, DS90UB929-Q1, DS90UB925Q-Q1, DS90UB925AQ-Q1, and DS90UB927Q-Q1 FPD-Link III
Serializers.
The configurations outlined in (2-lane FPD-Link III Input, 4 MIPI lanes Output, 2-lane FPD-Link III Input, 2 MIPI
lanes Output, 1- or 2-lane FPD-Link III Input, 2 or 4 MIPI lanes Output in Replicate) will apply to DS90UB949-Q1
and DS90UB947-Q1 FPD-Link III Serializers.
The device can be configured in following modes:
• 1-lane FPD-Link III Input, 4 MIPI lanes Output
• 1-lane FPD-Link III Input, 2 MIPI lanes Output
• 2-lane FPD-Link III Input, 4 MIPI lanes Output
• 2-lane FPD-Link III Input, 4 MIPI lanes Output
• 1- or 2-lane FPD-Link III Input, 2 or 4 MIPI lanes Output (Replicate)
8.4.1.1 1-lane FPD-Link III Input, 4 MIPI lanes Output
In this configuration the PCLK rate embedded within the 1-lane FPD-Link III frame can range from 25 MHz to 96
MHz, resulting in a link rate of 875 Mbps (35 bit * 25 MHz) to 3.36 Gbps (35 bit * 96 MHz). Each MIPI data lane
will operate at a speed of 7 * PCLK frequency; resulting in a data rate of 175 Mbps to 672 Mbps. The
corresponding MIPI transmit clock rate will operate between 87.5 MHz to 336 MHz.
8.4.1.2 1-lane FPD-Link III Input, 2 MIPI lanes Output
In this configuration the PCLK rate embedded within the 1-lane FPD-Link III frame can range from 25 MHz to 96
MHz, resulting in a link rate of 875 Mbps (35 bit * 25 MHz) to 3.36 Gbps (35 bit * 96 MHz). Each MIPI data lane
will operate at a speed of 14 * PCLK frequency; resulting in a data rate of 350 Mbps to 1344 Mbps. The
corresponding MIPI transmit clock rate will operate between 175 MHz to 672 MHz.
8.4.1.3 2-lane FPD-Link III Input, 4 MIPI lanes Output
In this configuration the PCLK rate embedded is split into 2-lane FPD-Link III frame and can range from 50 MHz
to 170 MHz, resulting in a link rate of 875 Mbps (35 bit * 25 MHz) to 2.975 Gbps (35 bit * 85 MHz). The
embedded datastreams from the received FPD-Link III inputs are merged in HS mode to form packets that carry
the video stream. Each MIPI data lane will operate at a speed of 7 * PCLK frequency, resulting in a data rate of
350 Mbps to 1190 Mbps. The corresponding MIPI transmit clock rate will operate between 175 MHz to 595 MHz.
36
Submit Documentation Feedback
Copyright © 2014–2016, Texas Instruments Incorporated
Product Folder Links: DS90UB940-Q1