Abstract: This application note describes the JTAG hardware boundary scan functions of the quad port single chip transceivers (SCTs). The JTAG functionality for the quad port devices is essentially the same as four separate DS21x5y devices daisy chained together. The DS21Q352, DS21Q354, DS21Q552, DS21Q554, and DS21Q55 do not have a single BSDL file because they are multichip modules that contain four separate die in the same package. The internal JTAG pins are either wired together in parallel or daisy chained as appropriate. The JTDI pin is connected to the JTDI input of the first die, while JTDO4 pin is connected to the JTDO output of the fourth die. JTRST, JTCLK, and JTMS are wired together in parallel. To complete the scan chain, four copies of the specific DS21x5y BSDL file need to be placed in the JTAG chain. The note contains a complete breakdown of the JTAG scan chain and explains how to access all of the boundary scan cells in the device. Introduction The JTAG functionality for the DS21Qx5y devices is essentially the same as four separate DS21x5y devices daisy chained together. The DS21Q352, DS21Q354, DS21Q552, and DS21Q554 do not have a single BSDL file because they are multichip modules that contain four separate die in the same package, with some of the pins wired together internally. The internal JTAG pins are either wired together in parallel or daisy chained as appropriate. The JTDI pin is connected to the JTDI input of the first die, while JTDO4 pin is connected to the JTDO output of the fourth die. JTRST, JTCLK, and JTMS are simply wired together in parallel. Because of this, four copies of the specific DS21x5y device BSDL file need to be placed in the JTAG chain for scanning the internal daisy chain of the DS21Qx5y. Recommendation for JTAG Design In most cases, the DS21Qx5y device symbol was created as a single entity. In reality, the base of the DS21Qx5y is simply a printed wire board with the DS21x5y die with the connections detailed in the DS21Qx5y data sheet. To solve this issue, some additional work may be required to reflect the fact that the device is actually made up of four separate die. If the DS21Qx5y device and associated BSDL files are being used in a simulation program, there are two possible solutions. The easiest way to solve this problem is to alter the netlist after the design is complete to account for the internal connections. Another way is to create a hierarchy in the design. It is fairly simple to layout an extra page or two of schematic to reflect these internal connections. If however there is no need for the simulation and the DS21Qx5y is only being run on a physical board, the BSDL files can simply be used as is. To alleviate the need for mapping individual pins on the BGA substrate the following Table 1 has been provided. The table contains the port location (SCT number), BGA pin, BSDL cell scan position, BSDL cell name, and other useful information. The table has been sorted by port location (SCT number) and then BSDL scan position. This should allow for easy access to the necessary information about which BSDL scan position maps to which port location and BGA pin number. The BSDL files for the various DS21x5y devices can be found on the web at: BSDL Files. Table 1. JTAG scan chain: BGA pin to BSDL cell mapping SCT PORT BGA PIN BSDL SCAN POSITION BSDL SCAN NAME I/O DATA SHEET SYMBOL DATA SHEET DESCRIPTION 1 -- 0 RCL Output -- Internal to Package 1 M1 1 A8MCLK Output 8MCLK1 8192 MHz Clock Based on RCLK1 1 M2 2 RCHBLK Output RCHBLK1 Receive Channel Block SCT1 1 H1 3 RSYSCLK Input RSYSCLK1 Receive System Clock SCT1 1 H2 4 RLOSLOTC Output RLOS/LOTC1 Receive LOS/LOTC SCT1 1 G1 5 RSYNC BiDir RSYNC1 Receive Sync SCT1 1 -- 6 -- Control -- Internal to Package 1 K4 7 RFSYNC Output RFSYNC1 Receive Frame Sync SCT1 1 L1 8 RMSYNC Output RMSYNC1 Receive Multiframe Sync SCT1 1 J2 9 RSER Output RSER1 Receive Serial Data SCT1 1 L2 10 RSIG Output RSIG1 Receive Signaling Output SCT1 1 K1 11 RSIGF Output RSIGF1 Receive Signaling Freeze SCT1 1 J1 12 RCHCLK Output RCHCLK1 Receive Channel Clock SCT1 1 L4 13 RPOSO Output RPOSO1 Receive Positive Data Output SCT1 1 L3 14 RNEGO Output RNEGO1 Receive Negative Data Output SCT1 1 M3 15 RCLKO Output RCLKO1 Receive Clock Output SCT1 1 M4 16 RCLKI Input RCLKI1 Receive Clock Input SCT1 1 R3 17 RNEGI Input RNEGI1 Receive Negative Data Input SCT1 1 R4 18 RPOSI Input RPOSI1 Receive Positive Data Input SCT1 1 -- 19 RDATA Output -- Internal to Package 1 N3 20 RCLK Output RCLK1 Receive Clock SCT1 1 F1 21 RLCLK Output RLCLK1 Receive Link Clock SCT1 1 G2 22 RLINK Output RLINK1 Receive Link Data SCT1 1 K3 23 WRRW Input Active-Low WR (R/Active-Low W) Write Input (Read/Write) 1 -- 24 FMS Input -- Internal to Package 1 P3 25 CS Input Active-Low CS1 Chip Select SCT1 1 N2 26 RDDS Input Active-Low RD (Active-Low DS) Read Input (Data Strobe) 1 P4 27 ALEASA7 Input A7/ALE Address Bus Bit 7/ALE 1 U8 28 A6 Input A6 Address Bus Bit 6 1 H4 29 A5 Input A5 Address Bus Bit 5 1 V8 30 A4 Input A4 Address Bus Bit 4 1 T4 31 A3 Input A3 Address Bus Bit 3 1 V2 32 A2 Input A2 Address Bus Bit 2 1 L17 33 A1 Input A1 Address Bus Bit 1 1 U3 34 A0 Input A0 Address Bus Bit 0 1 U4 35 D7AD7 BiDir D7/AD7 Data or Address/Data Bus Bit 7 1 V4 36 D6AD6 BiDir D6/AD6 Data or Address/Data Bus Bit 6 1 U5 37 D5AD5 BiDir D5/AD5 Data or Address/Data Bus Bit 5 1 U9 38 D4AD4 BiDir D4/AD4 Data or Address/Data Bus Bit 4 1 U7 39 D3AD3 BiDir D3/AD3 Data or Address/Data Bus Bit 3 1 W15 40 D2AD2 BiDir D2/AD2 Data or Address/Data Bus Bit 2 1 J19 41 D1AD1 BiDir D1/AD1 Data or Address/Data Bus Bit 1 1 U11 42 D0AD0 BiDir D0/AD0 Data or Address/Data Bus Bit 0 1 -- 43 -- Control -- Internal to Package 1 U10 44 MUX Input MUX Mux Bus Select 1 V9 45 CO Output CO1 Carry Output for IBO SCT1 1 V10 46 TCHCLK Output TCHCLK1 Transmit Channel Clock SCT1 1 W12 47 TSSYNC Input TSSYNC1 Transmit System Sync SCT1 1 W11 48 TSYSCLK Input TSYSCLK1 Transmit System Clock SCT1 1 -- 49 TDATA Input -- Internal to Package 1 -- 50 TESO Output -- Internal to Package 1 W10 51 TSIG Input TSIG1 Transmit Signaling Input SCT1 1 W9 52 TSER Input TSER1 Transmit Serial Data SCT1 1 Y9 53 TCLK Input TCLK1 Transmit Clock SCT1 1 V7 54 TPOSO Output TPOSO1 Transmit Positive Data Output SCT1 1 T3 55 TNEGO Output TNEGO1 Transmit Negative Data Output SCT1 1 W7 56 TCLKO Output TCLKO1 Transmit Clock Output SCT1 1 V6 57 TCLKI Input TCLKI1 Transmit Clock Input SCT1 1 R1 58 TNEGI Input TNEGI1 Transmit Negative Data Input SCT1 1 W3 59 TPOSI Input TPOSI1 Transmit Positive Data Input SCT1 1 V1 60 TSYNC BiDir TSYNC1 Transmit Sync SCT1 1 -- 61 -- Control -- Internal to Package 1 W6 62 CI Input CI1 Carry Input for IBO SCT1 1 W5 63 TLINK Input TLINK1 Transmit Link Data for SCT1 1 V3 64 TLCLK Output TLCLK1 Transmit Link Clock for SCT1 1 W1 65 TCHBLK Output TCHBLK1 Transmit Channel Block SCT1 1 U1 66 INT Output Active-Low INT Interrupt 1 -- 67 -- Internal -- Internal to Package 1 -- 68 -- Internal -- Internal to Package 1 U16 69 TEST Input TEST Test 1 -- 70 A8XCLK Output -- Internal to Package 1 K2 71 LIUC Input LIUC Line Interface Connect 1 P2 72 BTS Input BTS Bus Type Select 2 -- 0 RCL Output -- Internal to Package 2 H17 1 A8MCLK Output 8MCLK2 8192MHz Clock Based on RCLK2 2 G17 2 RCHBLK Output RCHBLK2 Receive Channel Block SCT2 2 F17 3 RSYSCLK Input RSYSCLK2 Receive System Clock SCT2 2 E17 4 RLOSLOTC Output RLOS/LOTC2 Receive LOS/LOTC SCT2 2 D12 5 RSYNC BiDir RSYNC2 Receive Sync SCT2 2 -- 6 -- Control -- Internal to Package 2 D17 7 RFSYNC Output RFSYNC2 Receive Frame Sync SCT2 2 D16 8 RMSYNC Output RMSYNC2 Receive Multiframe Sync SCT2 2 D15 9 RSER Output RSER2 Receive Serial Data SCT2 2 B16 10 RSIG Output RSIG2 Receive Signaling Output SCT2 2 C15 11 RSIGF Output RSIGF2 Receive Signaling Freeze SCT2 2 D14 12 RCHCLK Output RCHCLK2 Receive Channel Clock SCT2 2 A16 13 RPOSO Output RPOSO2 Receive Positive Data Output SCT2 2 B15 14 RNEGO Output RNEGO2 Receive Negative Data Output SCT2 2 C14 15 RCLKO Output RCLKO2 Receive Clock Output SCT2 2 A15 16 RCLKI Input RCLKI2 Receive Clock Input SCT2 2 D13 17 RNEGI Input RNEGI2 Receive Negative Data Input SCT2 2 B14 18 RPOSI Input RPOSI2 Receive Positive Data Input SCT2 2 -- 19 RDATA Output -- Internal to Package 2 B13 20 RCLK Output RCLK2 Receive Clock SCT2 2 A12 21 RLCLK Output RLCLK2 Receive Link Clock SCT2 2 A13 22 RLINK Output RLINK2 Receive Link Data SCT2 2 K3 23 WRRW Input Active-Low WR (R/Active-Low W) Write Input (Read/Write) 2 -- 24 FMS Input -- Internal to Package 2 A14 25 CS Input Active-Low CS2 Chip Select for SCT2 2 N2 26 RDDS Input Active-Low RD (Active-Low DS) Read Input (Data Strobe) 2 P4 27 ALEASA7 Input A7/ALE Address Bus Bit 7/ALE 2 U8 28 A6 Input A6 Address Bus Bit 6 2 H4 29 A5 Input A5 Address Bus Bit 5 2 V8 30 A4 Input A4 Address Bus Bit 4 2 T4 31 A3 Input A3 Address Bus Bit 3 2 V2 32 A2 Input A2 Address Bus Bit 2 2 L17 33 A1 Input A1 Address Bus Bit 1 2 U3 34 A0 Input A0 Address Bus Bit 0 2 U4 35 D7AD7 BiDir D7/AD7 Data or Address/Data Bus Bit 7 2 V4 36 D6AD6 BiDir D6/AD6 Data or Address/Data Bus Bit 6 2 U5 37 D5AD5 BiDir D5/AD5 Data or Address/Data Bus Bit 5 2 U9 38 D4AD4 BiDir D4/AD4 Data or Address/Data Bus Bit 4 2 U7 39 D3AD3 BiDir D3/AD3 Data or Address/Data Bus Bit 3 2 W15 40 D2AD2 BiDir D2/AD2 Data or Address/Data Bus Bit 2 2 J19 41 D1AD1 BiDir D1/AD1 Data or Address/Data Bus Bit 1 2 U11 42 D0AD0 BiDir D0/AD0 Data or Address/Data Bus Bit 0 2 -- 43 -- Control -- Internal to Package 2 U10 44 MUX Input MUX Mux Bus Select 2 B17 45 CO Output CO2 Carry Output for IBO SCT2 2 A18 46 TCHCLK Output TCHCLK2 Transmit Channel Clock SCT2 2 B18 47 TSSYNC Input TSSYNC2 Transmit System Sync SCT2 2 A19 48 TSYSCLK Input TSYSCLK2 Transmit System Clock SCT2 2 -- 49 TDATA Input -- Internal to Package 2 -- 50 TESO Output -- Internal to Package 2 C18 51 TSIG Input TSIG2 Transmit Signaling Input SCT2 2 C17 52 TSER Input TSER2 Transmit Serial Data SCT2 2 B19 53 TCLK Input TCLK2 Transmit Clock SCT2 2 C19 54 TPOSO Output TPOSO2 Transmit Positive Data Output SCT2 2 B20 55 TNEGO Output TNEGO2 Transmit Negative Data Output SCT2 2 E18 56 TCLKO Output TCLKO2 Transmit Clock Output SCT2 2 D19 57 TCLKI Input TCLKI2 Transmit Clock Input SCT2 2 F19 58 TNEGI Input TNEGI2 Transmit Negative Data Input SCT2 2 C20 59 TPOSI Input TPOSI2 Transmit Positive Data Intput SCT2 2 D20 60 TSYNC BiDir TSYNC2 Transmit Sync SCT2 2 -- 61 -- Control -- Internal to Package 2 F18 62 CI Input CI2 Carry Input for IBO SCT2 2 E19 63 TLINK Input TLINK2 Transmit Link Data for SCT2 2 E20 64 TLCLK Output TLCLK2 Transmit Link Clock for SCT2 2 F20 65 TCHBLK Output TCHBLK2 Transmit Channel Block SCT2 2 U1 66 INT Output Active-Low INT Interrupt 2 -- 67 -- Internal -- Internal to Package 2 -- 68 -- Internal -- Internal to Package 2 U16 69 TEST Input TEST Test 2 -- 70 A8XCLK Output -- Internal to Package 2 K2 71 LIUC Input LIUC Line Interface Connect 2 P2 72 BTS Input BTS Bus Type Select 3 -- 0 RCL Output -- Internal to Package 3 F4 1 A8MCLK Output 8MCLK3 8192 MHz Clock Based on RCLK3 3 G4 2 RCHBLK Output RCHBLK3 Receive Channel Block SCT3 3 G3 3 RSYSCLK Input RSYSCLK3 Receive System Clock SCT3 3 E1 4 RLOSLOTC Output RLOS/LOTC3 Receive LOS/LOTC SCT3 3 D1 5 RSYNC BiDir RSYNC3 Receive Sync SCT3 3 -- 6 -- Control -- Internal to Package 3 A2 7 RFSYNC Output RFSYNC3 Receive Frame Sync SCT3 3 F2 8 RMSYNC Output RMSYNC3 Receive Multiframe Sync SCT3 3 E2 9 RSER Output RSER3 Receive Serial Data SCT3 3 C1 10 RSIG Output RSIG3 Receive Signaling Output SCT3 3 D2 11 RSIGF Output RSIGF3 Receive Signaling Freeze SCT3 3 F3 12 RCHCLK Output RCHCLK3 Receive Channel Clock SCT3 3 B1 13 RPOSO Output RPOSO3 Receive Positive Data Output SCT3 3 C2 14 RNEGO Output RNEGO3 Receive Negative Data Output SCT3 3 B4 15 RCLKO Output RCLKO3 Receive Clock Output SCT3 3 A4 16 RCLKI Input RCLKI3 Receive Clock Input SCT3 3 A1 17 RNEGI Input RNEGI3 Receive Negative Data Input SCT3 3 B2 18 RPOSI Input RPOSI3 Receive Positive Data Input SCT3 3 -- 19 RDATA Output -- Internal to Package 3 E3 20 RCLK Output RCLK3 Receive Clock SCT3 3 D3 21 RLCLK Output RLCLK3 Receive Link Clock SCT3 3 A3 22 RLINK Output RLINK3 Receive Link Data SCT3 3 K3 23 WRRW Input Active-Low WR (R/Active-Low W) Write Input (Read/Write) 3 -- 24 FMS Input -- Internal to Package 3 B5 25 CS Input Active-Low CS3 Chip Select for SCT3 3 N2 26 RDDS Input Active-Low RD (Active-Low DS) Read Input (Data Strobe) 3 P4 27 ALEASA7 Input A7/ALE Address Bus Bit 7/ALE 3 U8 28 A6 Input A6 Address Bus Bit 6 3 H4 29 A5 Input A5 Address Bus Bit 5 3 V8 30 A4 Input A4 Address Bus Bit 4 3 T4 31 A3 Input A3 Address Bus Bit 3 3 V2 32 A2 Input A2 Address Bus Bit 2 3 L17 33 A1 Input A1 Address Bus Bit 1 3 U3 34 A0 Input A0 Address Bus Bit 0 3 U4 35 D7AD7 BiDir D7/AD7 Data or Address/Data Bus Bit 7 3 V4 36 D6AD6 BiDir D6/AD6 Data or Address/Data Bus Bit 6 3 U5 37 D5AD5 BiDir D5/AD5 Data or Address/Data Bus Bit 5 3 U9 38 D4AD4 BiDir D4/AD4 Data or Address/Data Bus Bit 4 3 U7 39 D3AD3 BiDir D3/AD3 Data or Address/Data Bus Bit 3 3 W15 40 D2AD2 BiDir D2/AD2 Data or Address/Data Bus Bit 2 3 J19 41 D1AD1 BiDir D1/AD1 Data or Address/Data Bus Bit 1 3 U11 42 D0AD0 BiDir D0/AD0 Data or Address/Data Bus Bit 0 3 -- 43 -- Control -- Internal to Package 3 U10 44 MUX Input MUX Mux Bus Select 3 A6 45 CO Output CO3 Carry Output for IBO SCT3 3 B8 46 TCHCLK Output TCHCLK3 Transmit Channel Clock SCT3 3 D10 47 TSSYNC Input TSSYNC3 Transmit System Sync SCT3 3 A11 48 TSYSCLK Input TSYSCLK3 Transmit System Clock SCT3 3 -- 49 TDATA Input -- Internal to Package 3 -- 50 TESO Output -- Internal to Package 3 A10 51 TSIG Input TSIG3 Transmit Signaling Input SCT3 3 C10 52 TSER Input TSER3 Transmit Serial Data SCT3 3 B10 53 TCLK Input TCLK3 Transmit Clock SCT3 3 C9 54 TPOSO Output TPOSO3 Transmit Positive Data Output SCT3 3 D9 55 TNEGO Output TNEGO3 Transmit Negative Data Output SCT3 3 A7 56 TCLKO Output TCLKO3 Transmit Clock Output SCT3 3 C8 57 TCLKI Input TCLKI3 Transmit Clock Input SCT3 3 D8 58 TNEGI Input TNEGI3 Transmit Negative Data Input SCT3 3 A8 59 TPOSI Input TPOSI3 Transmit Positive Data Input SCT3 3 C7 60 TSYNC BiDir TSYNC3 Transmit Sync SCT3 3 -- 61 -- Control -- Internal to Package 3 D7 62 CI Intput CI3 Carry Input for IBO SCT3 3 C6 63 TLINK Input TLINK3 Transmit Link Data for SCT3 3 D6 64 TLCLK Output TLCLK3 Transmit Link Clock for SCT3 3 C11 65 TCHBLK Output TCHBLK3 Transmit Channel Block SCT3 3 U1 66 INT Output Active-Low INT Interrupt for All Four SCTs 3 -- 67 -- Internal -- Internal to Package 3 -- 68 -- Internal -- Internal to Package 3 U16 69 TEST Input TEST Test 3 -- 70 A8XCLK Output -- Internal to Package 3 K2 71 LIUC Input LIUC Line Interface Connect 3 P2 72 BTS Input BTS Bus Type Select 4 -- 0 RCL Output -- Internal to Package 4 V13 1 A8MCLK Output 8MCLK4 8192MHz Clock Based on RCLK4 4 Y12 2 RCHBLK Output RCHBLK4 Receive Channel Block SCT4 4 W14 3 RSYSCLK Input RSYSCLK4 Receive System Clock SCT4 4 V11 4 RLOSLOTC Output RLOS/LOTC4 Receive LOS/LOTC SCT4 4 V12 5 RSYNC BiDir RSYNC4 Receive Sync SCT4 4 -- 6 -- Control -- Internal to Package 4 V14 7 RFSYNC Output RFSYNC4 Receive Frame Sync SCT4 4 W16 8 RMSYNC Output RMSYNC4 Receive Multiframe Sync SCT4 4 W17 9 RSER Output RSER4 Receive Serial Data SCT4 4 Y18 10 RSIG Output RSIG4 Receive Signaling Output SCT4 4 V16 11 RSIGF Output RSIGF4 Receive Signaling Freeze SCT4 4 U14 12 RCHCLK Output RCHCLK4 Receive Channel Clock SCT4 4 U15 13 RPOSO Output RPOSO4 Receive Positive Data Output SCT4 4 U17 14 RNEGO Output RNEGO4 Receive Negative Data Output SCT4 4 T17 15 RCLKO Output RCLKO4 Receive Clock Output SCT4 4 R17 16 RCLKI Input RCLKI4 Receive Clock Input SCT4 4 P17 17 RNEGI Input RNEGI4 Receive Negative Data Input SCT4 4 V15 18 RPOSI Input RPOSI4 Receive Positive Data Input SCT4 4 -- 19 RDATA Output -- Internal to Package 4 M18 20 RCLK Output RCLK4 Receive Clock SCT4 4 K18 21 RLCLK Output RLCLK4 Receive Link Clock SCT4 4 U12 22 RLINK Output RLINK4 Receive Link Data SCT4 4 K3 23 WRRW Input Active-Low WR (R/Active-Low W) Write Input (Read/Write) 4 -- 24 FMS Input -- Internal to Package 4 K17 25 CS Input Active-Low CS4 Chip Select for SCT4 4 N2 26 RDDS Input Active-Low RD (Active-Low DS) Read Input (Data Strobe) 4 P4 27 ALEASA7 Input A7/ALE Address Bus Bit 7/ALE 4 U8 28 A6 Input A6 Address Bus Bit 6 4 H4 29 A5 Input A5 Address Bus Bit 5 4 V8 30 A4 Input A4 Address Bus Bit 4 4 T4 31 A3 Input A3 Address Bus Bit 3 4 V2 32 A2 Input A2 Address Bus Bit 2 4 L17 33 A1 Input A1 Address Bus Bit 1 4 U3 34 A0 Input A0 Address Bus Bit 0 4 U4 35 D7AD7 BiDir D7/AD7 Data or Address/Data Bus Bit 7 4 V4 36 D6AD6 BiDir D6/AD6 Data or Address/Data Bus Bit 6 4 U5 37 D5AD5 BiDir D5/AD5 Data or Address/Data Bus Bit 5 4 U9 38 D4AD4 BiDir D4/AD4 Data or Address/Data Bus Bit 4 4 U7 39 D3AD3 BiDir D3/AD3 Data or Address/Data Bus Bit 3 4 W15 40 D2AD2 BiDir D2/AD2 Data or Address/Data Bus Bit 2 4 J19 41 D1AD1 BiDir D1/AD1 Data or Address/Data Bus Bit 1 4 U11 42 D0AD0 BiDir D0/AD0 Data or Address/Data Bus Bit 0 4 -- 43 -- Control -- Internal to Package 4 U10 44 MUX Input MUX Mux Bus Select 4 J20 45 CO Output CO4 Carry Output for IBO SCT4 4 L18 46 TCHCLK Output TCHCLK4 Transmit Channel Clock SCT4 4 K19 47 TSSYNC Input TSSYNC4 Transmit System Sync SCT4 4 N18 48 TSYSCLK Input TSYSCLK4 Transmit System Clock SCT4 4 -- 49 TDATA Input -- Internal to Package 4 -- 50 TESO Output -- Internal to Package 4 L19 51 TSIG Input TSIG4 Transmit Signaling Input SCT4 4 K20 52 TSER Input TSER4 Transmit Serial Data SCT4 4 M19 53 TCLK Input TCLK4 Transmit Clock SCT4 4 N19 54 TPOSO Output TPOSO4 Transmit Positive Data Output SCT4 4 N20 55 TNEGO Output TNEGO4 Transmit Negative Data Output SCT4 4 P19 56 TCLKO Output TCLKO4 Transmit Clock Output SCT4 4 P20 57 TCLKI Input TCLKI4 Transmit Clock Input SCT4 4 R20 58 TNEGI Input TNEGI4 Transmit Negative Data Input SCT4 4 R19 59 TPOSI Input TPOSI4 Transmit Positive Data Intput SCT4 4 R18 60 TSYNC BiDir TSYNC4 Transmit Sync SCT4 4 -- 61 -- Control -- Internal to Package 4 T20 62 CI Input CI4 Carry Input for IBO SCT4 4 T19 63 TLINK Input TLINK4 Transmit Link Data for SCT4 4 T18 64 TLCLK Output TLCLK4 Transmit Link Clock for SCT4 4 U20 65 TCHBLK Output TCHBLK4 Transmit Channel Block SCT4 4 U1 66 INT Output Active-Low INT Interrupt 4 -- 67 -- Internal -- Internal to Package 4 -- 68 -- Internal -- Internal to Package 4 U16 69 TEST Input TEST Test 4 -- 70 A8XCLK Output -- Internal to Package 4 K2 71 LIUC Input LIUC Line Interface Connect 4 P2 72 BTS Input BTS Bus Type Select We Want Your Feedback! Automatic Updates Would you like to be automatically notified when new application notes are published in your areas of interest? Sign up for EE-Mail™. More Information   APP 406: Jun 06, 2003 DS21Q352 Quad T1/E1 Transceiver (3.3V, 5.0V) Full Data Sheet (PDF, 176kB) Free Samples DS21Q354 Quad T1/E1 Transceiver (3.3V, 5.0V) Full Data Sheet (PDF, 176kB) Free Samples DS21Q55 Quad T1/E1/J1 Transceiver Full Data Sheet (PDF, 1.4MB) DS21Q552 Quad T1/E1 Transceiver (3.3V, 5.0V) Full Data Sheet (PDF, 176kB) Free Samples DS21Q554 Quad T1/E1 Transceiver (3.3V, 5.0V) Full Data Sheet (PDF, 176kB) Free Samples   Download, PDF Format (321kB)  AN406, AN 406, APP406, Appnote406, Appnote 406