SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 D D D D D D D D Members of the Texas Instruments SCOPE Family of Testability Products Members of the Texas Instruments Widebus Family Compatible With the IEEE Standard 1149.1-1990 (JTAG) Test Access Port and Boundary-Scan Architecture Include D-Type Flip-Flops and Control Circuitry to Provide Multiplexed Transmission of Stored and Real-Time Data Bus Hold on Data Inputs Eliminates the Need for External Pullup Resistors B-Port Outputs of ’ABTH182646A Devices Have Equivalent 25-Ω Series Resistors, So No External Resistors Are Required State-of-the-Art EPIC-ΙΙB BiCMOS Design D D One Boundary-Scan Cell Per I/O Architecture Improves Scan Efficiency SCOPE Instruction Set – IEEE Standard 1149.1-1990 Required Instructions and Optional CLAMP and HIGHZ – Parallel-Signature Analysis at Inputs – Pseudo-Random Pattern Generation From Outputs – Sample Inputs/Toggle Outputs – Binary Count From Outputs – Device Identification – Even-Parity Opcodes Packaged in 64-Pin Plastic Thin Quad Flat (PM) Packages Using 0.5-mm Center-to-Center Spacings and 68-Pin Ceramic Quad Flat (HV) Packages Using 25-mil Center-to-Center Spacings 1A2 1A1 1OE GND 1SAB 1CLKAB TDO VCC NC TMS 1CLKBA 1SBA 1DIR GND 1B1 1B2 1B3 SN54ABTH18646A, SN54ABTH182646A . . . HV PACKAGE (TOP VIEW) 9 8 7 6 5 4 3 2 1 68 67 66 65 64 63 62 61 10 60 11 59 12 58 13 57 14 56 15 55 16 54 17 53 18 52 19 51 20 50 21 49 22 48 23 47 24 46 25 45 1B4 1B5 1B6 GND 1B7 1B8 1B9 VCC NC 2B1 2B2 2B3 2B4 GND 2B5 2B6 2B7 TCK 2CLKBA 2SBA GND 2DIR 2B9 2B8 VCC 26 44 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 2A7 2A8 2A9 GND 2OE 2SAB 2CLKAB TDI NC 1A3 1A4 1A5 GND 1A6 1A7 1A8 1A9 NC VCC 2A1 2A2 2A3 GND 2A4 2A5 2A6 NC – No internal connection Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. SCOPE, Widebus, and EPIC-ΙΙB are trademarks of Texas Instruments Incorporated. Copyright 1996, Texas Instruments Incorporated UNLESS OTHERWISE NOTED this document contains PRODUCTION DATA information current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. On products compliant to MIL-PRF-38535, all parameters are tested unless otherwise noted. On all other products, production processing does not necessarily include testing of all parameters. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 1 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 1A2 1A1 1OE GND 1SAB 1CLKAB TDO V CC TMS 1CLKBA 1SBA 1DIR GND 1B1 1B2 1B3 SN74ABTH18646A, SN74ABTH182646A . . . PM PACKAGE (TOP VIEW) 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 1A3 1A4 1A5 GND 1A6 1A7 1A8 1A9 VCC 2A1 2A2 2A3 GND 2A4 2A5 2A6 1 48 2 47 3 46 4 45 5 44 6 43 7 42 8 41 9 40 10 39 11 38 12 37 13 36 14 35 15 34 16 33 1B4 1B5 1B6 GND 1B7 1B8 1B9 VCC 2B1 2B2 2B3 2B4 GND 2B5 2B6 2B7 2A7 2A8 2A9 GND 2OE 2SAB 2CLKAB TDI VCC TCK 2CLKBA 2SBA GND 2DIR 2B9 2B8 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 description The ’ABTH18646A and ’ABTH182646A scan test devices with 18-bit bus transceivers and registers are members of the Texas Instruments SCOPE testability integrated-circuit family. This family of devices supports IEEE Standard 1149.1-1990 boundary scan to facilitate testing of complex circuit-board assemblies. Scan access to the test circuitry is accomplished via the 4-wire test access port (TAP) interface. In the normal mode, these devices are 18-bit bus transceivers and registers that allow for multiplexed transmission of data directly from the input bus or from the internal registers. They can be used either as two 9-bit transceivers or one 18-bit transceiver. The test circuitry can be activated by the TAP to take snapshot samples of the data appearing at the device pins or to perform a self test on the boundary-test cells. Activating the TAP in the normal mode does not affect the functional operation of the SCOPE bus transceivers and registers. Transceiver function is controlled by output-enable (OE) and direction (DIR) inputs. When OE is low, the transceiver is active and operates in the A-to-B direction when DIR is high or in the B-to-A direction when DIR is low. When OE is high, both the A and B outputs are in the high-impedance state, effectively isolating both buses. Data flow is controlled by clock (CLKAB and CLKBA) and select (SAB and SBA) inputs. Data on the A bus is clocked into the associated registers on the low-to-high transition of CLKAB. When SAB is low, real-time A data is selected for presentation to the B bus (transparent mode). When SAB is high, stored A data is selected for presentation to the B bus (registered mode). The function of the CLKBA and SBA inputs mirrors that of CLKAB and SAB, respectively. Figure 1 shows the four fundamental bus-management functions that are performed with the ’ABTH18646A and ’ABTH182646A. 2 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 description (continued) In the test mode, the normal operation of the SCOPE bus transceivers and registers is inhibited, and the test circuitry is enabled to observe and control the I/O boundary of the device. When enabled, the test circuitry performs boundary-scan test operations according to the protocol described in IEEE Standard 1149.1-1990. Four dedicated test pins observe and control the operation of the test circuitry: test data input (TDI), test data output (TDO), test mode select (TMS), and test clock (TCK). Additionally, the test circuitry performs other testing functions such as parallel-signature analysis (PSA) on data inputs and pseudo-random pattern generation (PRPG) from data outputs. All testing and scan operations are synchronized to the TAP interface. Improved scan efficiency is accomplished through the adoption of a one boundary-scan cell (BSC) per I/O pin architecture. This architecture is implemented in such a way as to capture the most pertinent test data. A PSA/COUNT instruction also is included to ease the testing of memories and other circuits where a binary count addressing scheme is useful. Active bus-hold circuitry holds unused or floating data inputs at a valid logic level. The B-port outputs of ’ABTH182646A, which are designed to source or sink up to 12 mA, include 25-Ω series resistors to reduce overshoot and undershoot. The SN54ABTH18646A and SN54ABTH182646A are characterized for operation over the full military temperature range of –55°C to 125°C. The SN74ABTH18646A and SN74ABTH182646A are characterized for operation from –40°C to 85°C. FUNCTION TABLE (normal mode, each 9-bit section) INPUTS DATA I/O OE DIR CLKAB CLKBA SAB SBA A1 – A9 B1 – B9 X X ↑ X X X Input Unspecified† OPERATION OR FUNCTION X X X ↑ X X Unspecified† Input Store A, B unspecified† Store B, A unspecified† H X ↑ ↑ X X Input Input Store A and B data H X L L X X Input disabled Input disabled Isolation, hold storage L L X X X L Output Input Real-time B data to A bus L L X X X H Output Input disabled Stored B data to A bus L H X X L X Input Output Real-time A data to B bus L H X X H X Input disabled Output Stored A data to B bus † The data-output functions can be enabled or disabled by various signals at OE and DIR. Data-input functions are always enabled; i.e., data at the bus pins is stored on every low-to-high transition of the clock inputs. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS OE L DIR L CLKAB CLKBA X X SAB X BUS B BUS A BUS A BUS B SCBS166D – AUGUST 1993 – REVISED JULY 1996 SBA L OE L DIR H REAL-TIME TRANSFER BUS B TO BUS A DIR X X X CLKAB CLKBA X ↑ X ↑ ↑ ↑ SAB X X X SAB L SBA X BUS B BUS A SBA X X X STORAGE FROM A, B, OR A AND B OE DIR CLKAB CLKBA SAB SBA L L L H X X X X X H H X TRANSFER STORED DATA TO A AND/OR B Figure 1. Bus-Management Functions 4 CLKBA X REAL-TIME TRANSFER BUS A TO BUS B BUS B BUS A OE X X H CLKAB X POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 functional block diagram VCC 62 Boundary-Scan Register 1OE 1DIR 1CLKBA 1SBA 1CLKAB 1SAB 53 55 54 59 60 C1 1D 1A1 63 51 C1 1B1 1D One of Nine Channels VCC 21 2OE 2DIR 2CLKBA 2SBA 2CLKAB 2SAB 30 27 28 23 22 C1 1D 2A1 10 40 C1 1D 2B1 One of Nine Channels Bypass Register Boundary-Control Register Identification Register VCC 24 TDI VCC 56 TMS 26 TCK 58 Instruction Register TDO TAP Controller Pin numbers shown are for the PM package. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 5 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 Terminal Functions TERMINAL NAME Normal-function A-bus I/O ports. See function table for normal-mode logic. 1B1–1B9, 2B1–2B9 Normal-function B-bus I/O ports. See function table for normal-mode logic. 1CLKAB, 1CLKBA, 2CLKAB, 2CLKBA 1DIR, 2DIR GND 1OE, 2OE 1SAB, 1SBA, 2SAB, 2SBA 6 DESCRIPTION 1A1–1A9, 2A1–2A9 Normal-function clock inputs. See function table for normal-mode logic. Normal-function direction controls. See function table for normal-mode logic. Ground Normal-function output enables. See function table for normal-mode logic. An internal pullup at each terminal forces the terminal to a high level if left unconnected. Normal-function select controls. See function table for normal-mode logic. TCK Test clock. One of four terminals required by IEEE Standard 1149.1-1990. Test operations of the device are synchronous to TCK. Data is captured on the rising edge of TCK and outputs change on the falling edge of TCK. TDI Test data input. One of four terminals required by IEEE Standard 1149.1-1990. TDI is the serial input for shifting data through the instruction register or selected data register. An internal pullup forces TDI to a high level if left unconnected. TDO Test data output. One of four terminals required by IEEE Standard 1149.1-1990. TDO is the serial output for shifting data through the instruction register or selected data register. TMS Test mode select. One of four terminals required by IEEE Standard 1149.1-1990. TMS directs the device through its TAP controller states. An internal pullup forces TMS to a high level if left unconnected. VCC Supply voltage POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 test architecture Serial-test information is conveyed by means of a 4-wire test bus or TAP that conforms to IEEE Standard 1149.1-1990. All test instructions, test data, and test control signals are passed along this serial-test bus. The TAP controller monitors two signals from the test bus, TCK and TMS. The function of the TAP controller is to extract the synchronization (TCK) and state control (TMS) signals from the test bus and generate the appropriate on-chip control signals for the test structures in the device. Figure 2 shows the TAP-controller state diagram. The TAP controller is fully synchronous to the TCK signal. Input data is captured on the rising edge of TCK and output data changes on the falling edge of TCK. This scheme ensures data to be captured is valid for fully one-half of the TCK cycle. The functional block diagram shows the IEEE Standard 1149.1-1990 4-wire test bus and boundary-scan architecture and the relationship among the test bus, the TAP controller, and the test registers. As shown, the device contains an 8-bit instruction register and four test-data registers: a 52-bit boundary-scan register, a 3-bit boundary-control register, a 1-bit bypass register, and a 32-bit device-identification register. Test-Logic-Reset TMS = H TMS = L TMS = H TMS = H Run-Test/Idle TMS = H Select-DR-Scan Select-IR-Scan TMS = L TMS = L TMS = L TMS = H TMS = H Capture-DR Capture-IR TMS = L TMS = L Shift-DR Shift-IR TMS = L TMS = L TMS = H TMS = H TMS = H TMS = H Exit1-DR Exit1-IR TMS = L TMS = L Pause-DR Pause-IR TMS = L TMS = L TMS = H TMS = H TMS = L Exit2-DR TMS = L Exit2-IR TMS = H Update-DR TMS = H TMS = L TMS = H Update-IR TMS = H TMS = L Figure 2. TAP-Controller State Diagram POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 7 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 state diagram description The TAP controller is a synchronous finite state machine that provides test control signals throughout the device. The state diagram shown in Figure 2 is in accordance with IEEE Standard 1149.1-1990. The TAP controller proceeds through its states based on the level of TMS at the rising edge of TCK. As shown, the TAP controller consists of 16 states. There are six stable states (indicated by a looping arrow in the state diagram) and ten unstable states. A stable state is a state the TAP controller can retain for consecutive TCK cycles. Any state that does not meet this criterion is an unstable state. There are two main paths through the state diagram: one to access and control the selected data register and one to access and control the instruction register. Only one register can be accessed at a time. Test-Logic-Reset The device powers up in the Test-Logic-Reset state. In the stable Test-Logic-Reset state, the test logic is reset and is disabled so that the normal logic function of the device is performed. The instruction register is reset to an opcode that selects the optional IDCODE instruction, if supported, or the BYPASS instruction. Certain data registers also can be reset to their power-up values. The state machine is constructed such that the TAP controller returns to the Test-Logic-Reset state in no more than five TCK cycles if TMS is left high. The TMS pin has an internal pullup resistor that forces it high if left unconnected or if a board defect causes it to be open circuited. For the ’ABTH18646A and ’ABTH182646A, the instruction register is reset to the binary value 10000001, which selects the IDCODE instruction. Bits 51–48 in the boundary-scan register are reset to logic 0, ensuring that these cells, which control A-port and B-port outputs, are set to benign values (i.e., if test mode were invoked, the outputs would be at high-impedance state). Reset values of other bits in the boundary-scan register should be considered indeterminate. The boundary-control register is reset to the binary value 010, which selects the PSA test operation. Run-Test/Idle The TAP controller must pass through the Run-Test/Idle state (from Test-Logic-Reset) before executing any test operations. The Run-Test/Idle state also can be entered following-data register or instruction-register scans. Run-Test/Idle is provided as a stable state in which the test logic can be actively running a test or can be idle. The test operations selected by the boundary-control register are performed while the TAP controller is in the Run-Test/Idle state. Select-DR-Scan, Select-lR-Scan No specific function is performed in the Select-DR-Scan and Select-lR-Scan states, and the TAP controller exits either of these states on the next TCK cycle. These states allow the selection of either data-register scan or instruction-register scan. Capture-DR When a data-register scan is selected, the TAP controller must pass through the Capture-DR state. In the Capture-DR state, the selected data register can capture a data value as specified by the current instruction. Such capture operations occur on the rising edge of TCK, upon which the TAP controller exits the Capture-DR state. Shift-DR Upon entry to the Shift-DR state, the data register is placed in the scan path between TDI and TDO, and on the first falling edge of TCK, TDO goes from the high-impedance state to an active state. TDO enables to the logic level present in the least-significant bit of the selected data register. 8 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 Shift-DR (continued) While in the stable Shift-DR state, data is serially shifted through the selected data register on each TCK cycle. The first shift occurs on the first rising edge of TCK after entry to the Shift-DR state (i.e., no shifting occurs during the TCK cycle in which the TAP controller changes from Capture-DR to Shift-DR or from Exit2-DR to Shift-DR). The last shift occurs on the rising edge of TCK, upon which the TAP controller exits the Shift-DR state. Exit1-DR, Exit2-DR The Exit1-DR and Exit2-DR states are temporary states that end a data-register scan. It is possible to return to the Shift-DR state from either Exit1-DR or Exit2-DR without recapturing the data register. On the first falling edge of TCK after entry to Exit1-DR, TDO goes from the active state to the high-impedance state. Pause-DR No specific function is performed in the stable Pause-DR state, in which the TAP controller can remain indefinitely. The Pause-DR state can suspend and resume data register-scan operations without loss of data. Update-DR If the current instruction calls for the selected data register to be updated with current data, such update occurs on the falling edge of TCK, following entry to the Update-DR state. Capture-IR When an instruction-register scan is selected, the TAP controller must pass through the Capture-IR state. In the Capture-IR state, the instruction register captures its current status value. This capture operation occurs on the rising edge of TCK, upon which the TAP controller exits the Capture-IR state. For the ’ABTH18646A and ’ABTH182646A, the status value loaded in the Capture-IR state is the fixed binary value 10000001. Shift-IR Upon entry to the Shift-IR state, the instruction register is placed in the scan path between TDI and TDO, and on the first falling edge of TCK, TDO goes from the high-impedance state to an active state. TDO enables to the logic level present in the least-significant bit of the instruction register. While in the stable Shift-IR state, instruction data is serially shifted through the instruction register on each TCK cycle. The first shift occurs on the first rising edge of TCK after entry to the Shift-IR state (i.e., no shifting occurs during the TCK cycle, in which the TAP controller changes from Capture-IR to Shift-IR or from Exit2-IR to Shift-IR). The last shift occurs on the rising edge of TCK, upon which the TAP controller exits the Shift-IR state. Exit1-IR, Exit2-IR The Exit1-IR and Exit2-IR states are temporary states that end an instruction-register scan. It is possible to return to the Shift-IR state from either Exit1-IR or Exit2-IR without recapturing the instruction register. On the first falling edge of TCK after entry to Exit1-IR, TDO goes from the active state to the high-impedance state. Pause-IR No specific function is performed in the stable Pause-IR state, in which the TAP controller can remain indefinitely. The Pause-IR state can suspend and resume instruction-register scan operations without loss of data. Update-IR The current instruction is updated and takes effect on the falling edge of TCK, following entry to the Update-IR state. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 9 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 register overview With the exception of the bypass and device-identification registers, any test register can be thought of as a serial-shift register with a shadow latch on each bit. The bypass and device-identification registers differ in that they contain only a shift register. During the appropriate capture state (Capture-IR for instruction register, Capture-DR for data registers), the shift register can be parallel loaded from a source specified by the current instruction. During the appropriate shift state (Shift-IR or Shift-DR), the contents of the shift register are shifted out from TDO while new contents are shifted in at TDI. During the appropriate update state (Update-IR or Update-DR), the shadow latches are updated from the shift register. instruction register description The instruction register (IR) is eight bits long and tells the device what instruction is to be executed. Information contained in the instruction includes the mode of operation (either normal mode, in which the device performs its normal logic function, or test mode, in which the normal logic function is inhibited or altered), the test operation to be performed, which of the four data registers is to be selected for inclusion in the scan path during data-register scans, and the source of data to be captured into the selected data register during Capture-DR. Table 3 lists the instructions supported by the ’ABTH18646A and ’ABTH182646A. The even-parity feature specified for SCOPE devices is supported in this device. Bit 7 of the instruction opcode is the parity bit. Any instructions that are defined for SCOPE devices but are not supported by this device default to BYPASS. During Capture-IR, the IR captures the binary value 10000001. As an instruction is shifted in, this value is shifted out via TDO and can be inspected as verification that the IR is in the scan path. During Update-IR, the value that has been shifted into the IR is loaded into shadow latches. At this time, the current instruction is updated and any specified mode change takes effect. At power up or in the Test-Logic-Reset state, the IR is reset to the binary value 10000001, which selects the IDCODE instruction. The IR order of scan is shown in Figure 3. TDI Bit 7 Parity (MSB) Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Figure 3. Instruction Register Order of Scan 10 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 Bit 1 Bit 0 (LSB) TDO SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 data register description boundary-scan register The boundary-scan register (BSR) is 52 bits long. It contains one boundary-scan cell (BSC) for each normal-function input pin, one BSC for each normal-function I/O pin (one single cell for both input data and output data), and one BSC for each of the internally decoded output-enable signals (1OEA, 2OEA, 1OEB, 2OEB). The BSR is used 1) to store test data that is to be applied externally to the device output pins, and/or 2) to capture data that appears internally at the outputs of the normal on-chip logic and/or externally at the device input pins. The source of data to be captured into the BSR during Capture-DR is determined by the current instruction. The contents of the BSR can change during Run-Test/Idle as determined by the current instruction. At power up or in Test-Logic-Reset, BSCs 51–48 are reset to logic 0, ensuring that these cells, which control A-port and B-port outputs, are set to benign values (i.e., if test mode were invoked, the outputs would be at high-impedance state). Reset values of other BSCs should be considered indeterminate. When external data is to be captured, the BSCs for signals 1OEA, 2OEA, 1OEB, and 2OEB capture logic values determined by the following positive-logic equations: 1OEA = 1OE • 1DIR, 2OEA = 2OE • 2DIR, 1OEB = 1OE • DIR, and 2OEB = 2OE • DIR. When data is to be applied externally, these BSCs control the drive state (active or high impedance) of their respective outputs. The BSR order of scan is from TDI through bits 51–0 to TDO. Table 1 shows the BSR bits and their associated device pin signals. Table 1. Boundary-Scan Register Configuration BSR BIT NUMBER DEVICE SIGNAL BSR BIT NUMBER DEVICE SIGNAL BSR BIT NUMBER DEVICE SIGNAL 51 2OEB 35 2A9-I/O 17 2B9-I/O 50 1OEB 34 2A8-I/O 16 2B8-I/O 49 2OEA 33 2A7-I/O 15 2B7-I/O 48 1OEA 32 2A6-I/O 14 2B6-I/O 47 2DIR 31 2A5-I/O 13 2B5-I/O 46 1DIR 30 2A4-I/O 12 2B4-I/O 45 2OE 29 2A3-I/O 11 2B3-I/O 44 1OE 28 2A2-I/O 10 2B2-I/O 43 2CLKAB 27 2A1-I/O 9 2B1-I/O 42 1CLKAB 26 1A9-I/O 8 1B9-I/O 41 2CLKBA 25 1A8-I/O 7 1B8-I/O 40 1CLKBA 24 1A7-I/O 6 1B7-I/O 39 2SAB 23 1A6-I/O 5 1B6-I/O 38 1SAB 22 1A5-I/O 4 1B5-I/O 37 2SBA 21 1A4-I/O 3 1B4-I/O 36 1SBA 20 1A3-I/O 2 1B3-I/O 19 1A2-I/O 1 1B2-I/O 18 1A1-I/O 0 1B1-I/O POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 11 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 boundary-control register The boundary-control register (BCR) is three bits long. The BCR is used in the context of the boundary-run test (RUNT) instruction to implement additional test operations not included in the basic SCOPE instruction set. Such operations include PRPG, PSA, and binary count up (COUNT). Table 4 shows the test operations that are decoded by the BCR. During Capture-DR, the contents of the BCR are not changed. At power up or in Test-Logic-Reset, the BCR is reset to the binary value 010, which selects the PSA test operation. The BCR order of scan is shown in Figure 4. TDI Bit 2 (MSB) Bit 1 Bit 0 (LSB) TDO Figure 4. Boundary-Control Register Order of Scan bypass register The bypass register is a 1-bit scan path that can be selected to shorten the length of the system scan path, reducing the number of bits per test pattern that must be applied to complete a test operation. During Capture-DR, the bypass register captures a logic 0. The bypass register order of scan is shown in Figure 5. TDI Bit 0 TDO Figure 5. Bypass Register Order of Scan 12 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 device-identification register The device-identification register (IDR) is 32 bits long. It can be selected and read to identify the manufacturer, part number, and version of this device. For the ’ABTH18646A , the binary value 00000000000000101001000000101111 (0002902F, hex) is captured (during Capture-DR state) in the IDR to identify this device as Texas Instruments SN54/74ABTH18646A. For the ’ABTH182646A , the binary value 00000000000000101101000000101111 (0002D02F, hex) is captured (during Capture-DR state) in the IDR to identify this device as Texas Instruments SN54/74ABTH182646A. The IDR order of scan is from TDI through bits 31–0 to TDO. Table 2 shows the IDR bits and their significance. Table 2. Device-Identification Register Configuration IDR BIT NUMBER IDENTIFICATION SIGNIFICANCE IDR BIT NUMBER IDENTIFICATION SIGNIFICANCE IDR BIT NUMBER IDENTIFICATION SIGNIFICANCE 31 VERSION3 27 PARTNUMBER15 11 30 VERSION2 26 PARTNUMBER14 10 MANUFACTURER10† MANUFACTURER09† 29 VERSION1 25 PARTNUMBER13 9 28 VERSION0 24 PARTNUMBER12 8 23 PARTNUMBER11 7 22 PARTNUMBER10 6 21 PARTNUMBER09 5 20 PARTNUMBER08 4 19 PARTNUMBER07 3 18 PARTNUMBER06 2 17 PARTNUMBER05 1 16 PARTNUMBER04 0 MANUFACTURER00† LOGIC1† 15 PARTNUMBER03 14 PARTNUMBER02 13 PARTNUMBER01 MANUFACTURER08† MANUFACTURER07† MANUFACTURER06† MANUFACTURER05† MANUFACTURER04† MANUFACTURER03† MANUFACTURER02† MANUFACTURER01† 12 PARTNUMBER00 † Note that for TI products, bits 11–0 of the device-identification register always contain the binary value 000000101111 (02F, hex). POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 13 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 instruction-register opcode description The instruction-register opcodes are shown in Table 3. The following descriptions detail the operation of each instruction. Table 3. Instruction-Register Opcodes BINARY CODE† BIT 7 → BIT 0 MSB → LSB SCOPE OPCODE DESCRIPTION SELECTED DATA REGISTER MODE 00000000 EXTEST Boundary scan Boundary scan Test 10000001 IDCODE Identification read Device identification Normal 10000010 SAMPLE/PRELOAD BYPASS‡ Sample boundary Boundary scan Normal Bypass scan Bypass Normal Bypass scan Bypass Normal 00000101 BYPASS‡ BYPASS‡ Bypass scan Bypass Normal 00000110 HIGHZ Control boundary to high impedance Bypass Modified test 10000111 CLAMP BYPASS‡ Control boundary to 1/0 Bypass Test 10001000 Bypass scan Bypass Normal 00001001 RUNT Boundary-run test Bypass Test 00001010 READBN Boundary read Boundary scan Normal 10001011 READBT Boundary read Boundary scan Test 00001100 CELLTST Boundary self test Boundary scan Normal 10001101 TOPHIP Boundary toggle outputs Bypass Test 10001110 SCANCN Boundary-control register scan Boundary control Normal 00001111 SCANCT Boundary-control register scan Boundary control Test All others BYPASS Bypass scan Bypass Normal 00000011 10000100 † Bit 7 is used to maintain even parity in the 8-bit instruction. ‡ The BYPASS instruction is executed in lieu of a SCOPE instruction that is not supported in the ’ABTH18646A or ’ABTH182646A. boundary scan This instruction conforms to the IEEE Standard 1149.1-1990 EXTEST instruction. The BSR is selected in the scan path. Data appearing at the device input and I/O pins is captured in the associated BSCs. Data that has been scanned into the I/O BSCs for pins in the output mode is applied to the device I/O pins. Data present at the device pins is passed through the BSCs to the normal on-chip logic. For I/O pins, the operation of a pin as input or output is determined by the contents of the output-enable BSCs (bits 51–48 of the BSR). When a given output enable is active (logic 1), the associated I/O pins operate in the output mode. Otherwise, the I/O pins operate in the input mode. The device operates in the test mode. identification read This instruction conforms to the IEEE Standard 1149.1-1990 IDCODE instruction. The IDR is selected in the scan path. The device operates in the normal mode. sample boundary This instruction conforms to the IEEE Standard 1149.1-1990 SAMPLE/PRELOAD instruction. The BSR is selected in the scan path. Data appearing at the device input pins and I/O pins in the input mode is captured in the associated BSCs, while data appearing at the outputs of the normal on-chip logic is captured in the BSCs associated with I/O pins in the output mode. The device operates in the normal mode. 14 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 bypass scan This instruction conforms to the IEEE Standard 1149.1-1990 BYPASS instruction. The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. The device operates in the normal mode. control boundary to high impedance This instruction conforms to the IEEE Standard 1149.1a-1993 HIGHZ instruction. The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. The device operates in a modified test mode in which all device I/O pins are placed in the high-impedance state, the device input pins remain operational, and the normal on-chip logic function is performed. control boundary to 1/0 This instruction conforms to the IEEE Standard 1149.1a-1993 CLAMP instruction. The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. Data in the I/O BSCs for pins in the output mode is applied to the device I/O pins. The device operates in the test mode. boundary-run test The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. The device operates in the test mode. The test operation specified in the BCR is executed during Run-Test/Idle. The five test operations decoded by the BCR are: sample inputs/toggle outputs (TOPSIP), PRPG, PSA, simultaneous PSA and PRPG (PSA/PRPG), and simultaneous PSA and binary count up (PSA/COUNT). boundary read The BSR is selected in the scan path. The value in the BSR remains unchanged during Capture-DR. This instruction is useful for inspecting data after a PSA operation. boundary self test The BSR is selected in the scan path. All BSCs capture the inverse of their current values during Capture-DR. In this way, the contents of the shadow latches can be read out to verify the integrity of both shift-register and shadow-latch elements of the BSR. The device operates in the normal mode. boundary toggle outputs The bypass register is selected in the scan path. A logic 0 value is captured in the bypass register during Capture-DR. Data in the shift-register elements of the selected output-mode BSCs is toggled on each rising edge of TCK in Run-Test/Idle, updated in the shadow latches, and applied to the associated device I/O pins on each falling edge of TCK in Run-Test/Idle. Data in the input-mode BSCs remains constant. Data appearing at the device input or I/O pins is not captured in the input-mode BSCs. The device operates in the test mode. boundary-control-register scan The BCR is selected in the scan path. The value in the BCR remains unchanged during Capture-DR. This operation must be performed before a boundary-run test operation to specify which test operation is to be executed. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 15 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 boundary-control register opcode description The BCR opcodes are decoded from BCR bits 2–0 as shown in Table 4. The selected test operation is performed while the RUNT instruction is executed in the Run-Test/Idle state. The following descriptions detail the operation of each BCR instruction and illustrate the associated PSA and PRPG algorithms. Table 4. Boundary-Control Register Opcodes BINARY CODE BIT 2 → BIT 0 MSB → LSB DESCRIPTION X00 Sample inputs/toggle outputs (TOPSIP) X01 Pseudo-random pattern generation/36-bit mode (PRPG) X10 Parallel-signature analysis/36-bit mode (PSA) 011 Simultaneous PSA and PRPG/18-bit mode (PSA/PRPG) 111 Simultaneous PSA and binary count up/18-bit mode (PSA/COUNT) While the control input BSCs (bits 51–36) are not included in the toggle, PSA, PRPG, or COUNT algorithms, the output-enable BSCs (bits 51–48 of the BSR) control the drive state (active or high impedance) of the selected device output pins. These BCR instructions are valid only when both bytes of the device are operating in one direction of data flow (that is, 1OEA ≠ 1OEB and 2OEA ≠ 2OEB) and in the same direction of data flow (that is, 1OEA = 2OEA and 1OEB = 2OEB). Otherwise, the bypass instruction is operated. sample inputs/toggle outputs (TOPSIP) Data appearing at the selected device input-mode I/O pins is captured in the shift-register elements of the associated BSCs on each rising edge of TCK. Data in the shift-register elements of the selected output-mode BSCs is toggled on each rising edge of TCK, updated in the shadow latches, and applied to the associated device I/O pins on each falling edge of TCK. 16 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 pseudo-random pattern generation (PRPG) A pseudo-random pattern is generated in the shift-register elements of the selected BSCs on each rising edge of TCK, updated in the shadow latches, and applied to the associated device output-mode I/O pins on each falling edge of TCK. Figures 6 and 7 illustrate the 36-bit linear-feedback shift-register algorithms through which the patterns are generated. An initial seed value should be scanned into the BSR before performing this operation. A seed value of all zeroes does not produce additional patterns. 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O = Figure 6. 36-Bit PRPG Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1) POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 17 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 pseudo-random pattern generation (PRPG) (continued) 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O = Figure 7. 36-Bit PRPG Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0) 18 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 parallel-signature analysis (PSA) Data appearing at the selected device input-mode I/O pins is compressed into a 36-bit parallel signature in the shift-register elements of the selected BSCs on each rising edge of TCK. Data in the shadow latches of the selected output-mode BSCs remains constant and is applied to the associated device I/O pins. Figures 8 and 9 illustrate the 36-bit linear-feedback shift-register algorithms through which the signature is generated. An initial seed value should be scanned into the BSR before performing this operation. 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O = = Figure 8. 36-Bit PSA Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1) POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 19 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 parallel-signature analysis (PSA) (continued) 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O = = Figure 9. 36-Bit PSA Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0) 20 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 simultaneous PSA and PRPG (PSA/PRPG) Data appearing at the selected device input-mode I/O pins is compressed into an 18-bit parallel signature in the shift-register elements of the selected input-mode BSCs on each rising edge of TCK. At the same time, an 18-bit pseudo-random pattern is generated in the shift-register elements of the selected output-mode BSCs on each rising edge of TCK, updated in the shadow latches, and applied to the associated device I/O pins on each falling edge of TCK. Figures 10 and 11 illustrate the 18-bit linear-feedback shift-register algorithms through which the signature and patterns are generated. An initial seed value should be scanned into the BSR before performing this operation. A seed value of all zeroes does not produce additional patterns. 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O = = Figure 10. 18-Bit PSA/PRPG Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1) POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 21 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 simultaneous PSA and PRPG (PSA/PRPG) (continued) 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O = = Figure 11. 18-Bit PSA/PRPG Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0) 22 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 simultaneous PSA and binary count up (PSA/COUNT) Data appearing at the selected device input-mode I/O pins is compressed into an 18-bit parallel signature in the shift-register elements of the selected input-mode BSCs on each rising edge of TCK. At the same time, an 18-bit binary count-up pattern is generated in the shift-register elements of the selected output-mode BSCs on each rising edge of TCK, updated in the shadow latches, and applied to the associated device I/O pins on each falling edge of TCK. Figures 12 and 13 illustrate the 18-bit linear-feedback shift-register algorithms through which the signature is generated. An initial seed value should be scanned into the BSR before performing this operation. 2A9-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O MSB 2B9-I/O LSB = = 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O Figure 12. 18-Bit PSA/COUNT Configuration (1OEA = 2OEA = 0, 1OEB = 2OEB = 1) POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 23 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 simultaneous PSA and binary count up (PSA/COUNT) (continued) 2B9-I/O 2B8-I/O 2B7-I/O 2B6-I/O 2B5-I/O 2B4-I/O 2B3-I/O 2B2-I/O 2B1-I/O 1B9-I/O 1B8-I/O 1B7-I/O 1B6-I/O 1B5-I/O 1B4-I/O 1B3-I/O 1B2-I/O 1B1-I/O 2A8-I/O 2A7-I/O 2A6-I/O 2A5-I/O 2A4-I/O 2A3-I/O 2A2-I/O 2A1-I/O MSB 2A9-I/O LSB = = 1A9-I/O 1A8-I/O 1A7-I/O 1A6-I/O 1A5-I/O 1A4-I/O 1A3-I/O 1A2-I/O 1A1-I/O Figure 13. 18-Bit PSA/COUNT Configuration (1OEA = 2OEA = 1, 1OEB = 2OEB = 0) 24 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 timing description All test operations of the ’ABTH18646A and ’ABTH182646A are synchronous to TCK. Data on the TDI, TMS, and normal-function inputs is captured on the rising edge of TCK. Data appears on the TDO and normal-function output pins on the falling edge of TCK. The TAP controller is advanced through its states (as shown in Figure 2) by changing the value of TMS on the falling edge of TCK and then applying a rising edge to TCK. A simple timing example is shown in Figure 14. In this example, the TAP controller begins in the Test-Logic-Reset state and is advanced through its states, as necessary, to perform one instruction-register scan and one data-register scan. While in the Shift-IR and Shift-DR states, TDI is used to input serial data, and TDO is used to output serial data. The TAP controller is then returned to the Test-Logic-Reset state. Table 5 details the operation of the test circuitry during each TCK cycle. Table 5. Explanation of Timing Example TCK CYCLE(S) TAP STATE AFTER TCK DESCRIPTION 1 Test-Logic-Reset TMS is changed to a logic 0 value on the falling edge of TCK to begin advancing the TAP controller toward the desired state. 2 Run-Test/Idle 3 Select-DR-Scan 4 Select-IR-Scan 5 Capture-IR The IR captures the 8-bit binary value 10000001 on the rising edge of TCK as the TAP controller exits the Capture-IR state. 6 Shift-IR TDO becomes active and TDI is made valid on the falling edge of TCK. The first bit is shifted into the TAP on the rising edge of TCK as the TAP controller advances to the next state. Shift-IR One bit is shifted into the IR on each TCK rising edge. With TDI held at a logic 1 value, the 8-bit binary value 11111111 is serially scanned into the IR. At the same time, the 8-bit binary value 10000001 is serially scanned out of the IR via TDO. In TCK cycle 13, TMS is changed to a logic 1 value to end the IR scan on the next TCK cycle. The last bit of the instruction is shifted as the TAP controller advances from Shift-IR to Exit1-IR. 14 Exit1-IR TDO becomes inactive (goes to the high-impedance state) on the falling edge of TCK. 15 Update-IR 16 Select-DR-Scan 17 Capture-DR The bypass register captures a logic 0 value on the rising edge of TCK as the TAP controller exits the Capture-DR state. 18 Shift-DR TDO becomes active and TDI is made valid on the falling edge of TCK. The first bit is shifted into the TAP on the rising edge of TCK as the TAP controller advances to the next state. 19–20 Shift-DR The binary value 101 is shifted in via TDI, while the binary value 010 is shifted out via TDO. 21 Exit1-DR TDO becomes inactive (goes to the high-impedance state) on the falling edge of TCK. 22 Update-DR 23 Select-DR-Scan 7–13 24 Select-IR-Scan 25 Test-Logic-Reset The IR is updated with the new instruction (BYPASS) on the falling edge of TCK. In general, the selected data register is updated with the new data on the falling edge of TCK. Test operation completed POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 25 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 timing description (continued) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Select-IR-Scan Select-DR-Scan Update-DR Exit1-DR Capture-DR ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎ Test-Logic-Reset ÎÎ Select-DR-Scan Shift-IR Capture-IR Select-IR-Scan Select-DR-Scan Run-Test/Idle TAP Controller State Test-Logic-Reset TDO ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎ ÎÎÎÎÎÎ Update-IR ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ ÎÎÎÎÎÎÎÎÎ TDI Exit1-IR TMS Shift-DR TCK 3-State (TDO) or Don’t Care (TDI) Figure 14. Timing Example absolute maximum ratings over operating free-air temperature range (unless otherwise noted)† Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V Input voltage range, VI: except I/O ports (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V I/O ports (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 5.5 V Voltage range applied to any output in the high state or power-off state, VO . . . . . . . . . . . . . . –0.5 V to 5.5 V Current into any output in the low state, IO: SN54ABTH18646A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 mA SN54ABTH182646A (A port or TDO) . . . . . . . . . . . . . . . . 96 mA SN54ABTH182646A (B port) . . . . . . . . . . . . . . . . . . . . . . . 30 mA SN74ABTH18646A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 mA SN74ABTH182646A (A port or TDO) . . . . . . . . . . . . . . . 128 mA SN74ABTH182646A (B port) . . . . . . . . . . . . . . . . . . . . . . . 30 mA Input clamp current, IIK (VI < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –18 mA Output clamp current, IOK (VO < 0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –50 mA Maximum package power dissipation at TA = 55°C (in still air) (see Note 2): PM package . . . . . . . . . . . 1 W Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 65°C to 150°C † Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. The input and output negative-voltage ratings may be exceeded if the input and output clamp-current ratings are observed. 2. The maximum package power dissipation is calculated using a junction temperature of 150°C and a board trace length of 75 mils. For more information, refer to the Package Thermal Considerations application note in the ABT Advanced BiCMOS Technology Data Book, literature number SCBD002. 26 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 recommended operating conditions SN54ABTH18646A SN74ABTH18646A MIN MAX MIN MAX 4.5 5.5 4.5 5.5 UNIT VCC VIH Supply voltage VIL VI Low-level input voltage IOH IOL High-level output current VCC –24 Low-level output current 48 64 mA ∆t/∆v Input transition rise or fall rate 10 10 ns/V TA Operating free-air temperature 85 °C High-level input voltage 2 2 0.8 Input voltage 0 –55 125 0 –40 V V 0.8 V VCC –32 V mA electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) SN54ABTH18646A PARAMETER VIK VOH VOL II CLK, DIR, S, TCK VCC = 0 to 5.5 V, A or B ports TEST CONDITIONS VCC = 4.5 V, VCC = 4.5 V, II = –18 mA IOH = –3 mA VCC = 5 V, VCC = 4.5 V, IOH = –3 mA IOH = –24 mA VCC = 4.5 V, IOL = 48 mA VCC = 0 to 5.5 V, IIH IIL OE, TDI, TMS VCC = 5.5 V, VCC = 5.5 V, OE, TDI, TMS VCC = 5.5 V, II(hold) I(h ld)‡ A or B ports VCC = 4 4.5 5V IOZH IOZL TDO VCC = 5.5 V, VCC = 5.5 V, IOZPU TDO IOZPD TDO Ioff ICEX IO§ Outputs high TDO Outputs high ICC Outputs low Outputs disabled TA = 25°C TA = –55°C to 125°C † MIN MAX MIN MAX TYP –1.2 2.5 3 3 2 2 0.55 VI = VCC or GND ±1 ±1 VI = VCC or GND VI = VCC ±20 ±20 VI = GND VI = 0.8 V –40 75 220 500 VI = 2 V VO = 2.7 V, OE = 2 V –75 –180 –500 VO = 0.5 V, VCC = 0 to 2.1 V, VO = 2.7 V or 0.5 V, VCC = 2.1 V to 0, VO = 2.7 V or 0.5 V, OE = 2 V OE = 0.8 V OE = 0.8 V VCC = 0, VCC = 5.5 V, VI or VO ≤ 4.5 V VO = 5.5 V VCC = 5.5 V, VO = 2.5 V VCC = 5.5 V, IO = 0, VI = VCC or GND 10 –150 Ci Control inputs Cio A or B ports –40 VI = 2.5 V or 0.5 V VO = 2.5 V or 0.5 V 10 µA µA 10 10 µA –10 –10 µA ±50 µA ±50 µA µA –50 • DALLAS, TEXAS 75265 50 µA –200 mA –110 –200 1.7 3.9 3.9 20 24 24 1 3 3 1.5 1.5 mA mA 5 pF 10 pF Co TDO VO = 2.5 V or 0.5 V 8 † All typical values are at VCC = 5 V. ‡ The parameter II(hold) includes the off-state output leakage current. § Not more than one output should be tested at a time, and the duration of the test should not exceed one second. ¶ This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND. POST OFFICE BOX 655303 µ µA µA 50 A or B ports V –150 ±100 –50 V V 0.55 VCC = 5.5 V, One input at 3.4 V, Other inputs at VCC or GND ∆ICC¶ –1.2 2.5 UNIT pF 27 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) SN74ABTH18646A PARAMETER VIK VOH TEST CONDITIONS VCC = 4.5 V, VCC = 4.5 V, II = –18 mA IOH = –3 mA VCC = 5 V, VCC = 4 4.5 5V VOL II VCC = 4 4.5 5V CLK, DIR, S, TCK VCC = 0 to 5.5 V, A or B ports TA = 25°C MIN TYP† MAX TA = –40°C to 85°C MIN MAX –1.2 –1.2 2.5 2.5 IOH = –3 mA IOH = –24 mA 3 3 IOH = –32 mA IOL = 48 mA 2 UNIT V V 2 2 IOL = 64 mA 0.55 0.55 0.55 0.55 VCC = 0 to 5.5 V, VI = VCC or GND ±1 ±1 VI = VCC or GND VI = VCC ±20 ±20 VI = GND VI = 0.8 V –40 75 220 500 75 500 VI = 2 V –75 –180 –500 –75 –500 V µ µA IIH IIL OE, TDI, TMS VCC = 5.5 V, VCC = 5.5 V, OE, TDI, TMS VCC = 5.5 V, II(hold)‡ A or B ports VCC = 4 4.5 5V IOZH TDO VCC = 2.1 V to 5.5 V, VO = 2.7 V, OE = 2 V 10 10 µA IOZL TDO VCC = 2.1 V to 5.5 V, VO = 0.5 V, OE = 2 V –10 –10 µA IOZPU TDO VCC = 0 to 2.1 V, VO = 2.7 V or 0.5 V, OE = 0.8 V ±50 ±50 µA IOZPD TDO VCC = 2.1 V to 0, VO = 2.7 V or 0.5 V, OE = 0.8 V ±50 ±50 µA VCC = 0, VCC = 5.5 V, VI or VO ≤ 4.5 V VO = 5.5 V ±100 ±100 µA VCC = 5.5 V, VO = 2.5 V VCC = 5.5 V, IO = 0, VI = VCC or GND A or B ports Ioff ICEX Outputs high IO§ Outputs high ICC Outputs low Outputs disabled 10 –150 50 –50 Ci Control inputs Cio A or B ports VI = 2.5 V or 0.5 V VO = 2.5 V or 0.5 V –50 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 µA µA µA 50 µA –200 mA –200 1.7 2.2 2.2 20 24 24 1 2 2 1.5 1.5 mA mA 5 pF 10 pF Co TDO VO = 2.5 V or 0.5 V 8 † All typical values are at VCC = 5 V. ‡ The parameter II(hold) includes the off-state output leakage current. § Not more than one output should be tested at a time, and the duration of the test should not exceed one second. ¶ This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND. 28 10 –150 –110 VCC = 5.5 V, One input at 3.4 V, Other inputs at VCC or GND ∆ICC¶ –40 pF SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 timing requirements over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (normal mode) (see Figure 15) SN54ABTH18646A SN74ABTH18646A MIN MAX MIN MAX 100 0 100 UNIT fclock tw Clock frequency CLKAB or CLKBA 0 Pulse duration CLKAB or CLKBA high or low 3 3 MHz ns tsu th Setup time A before CLKAB↑ or B before CLKBA↑ 3 3 ns Hold time A after CLKAB↑ or B after CLKBA↑ 0.9 0.5 ns timing requirements over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (test mode) (see Figure 15) SN54ABTH18646A fclock tw tsu SN74ABTH18646A MIN MAX MIN MAX 50 0 50 Clock frequency TCK 0 Pulse duration TCK high or low 8 8 A, B, CLK, DIR, OE, or S before TCK↑ 6 6 4.5 4.5 Setup time TDI before TCK↑ TMS before TCK↑ Hold time td tr Delay time MHz ns ns 3 3 1.5 1.5 1 1 TMS after TCK↑ 1.5 1.5 Power up to TCK↑ 50* 50 ns 1* 1 µs A, B, CLK, DIR, OE, or S after TCK↑ th UNIT TDI after TCK↑ Rise time VCC power up *On products compliant to MIL-PRF-38535, this parameter is not production tested. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 ns 29 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 switching characteristics over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (normal mode) (see Figure 15) SN54ABTH18646A PARAMETER fmax tPLH tPHL tPLH tPHL tPLH tPHL tPZH tPZL tPZH tPZL tPHZ tPLZ tPHZ tPLZ FROM (INPUT) TO (OUTPUT) CLKAB or CLKBA A or B B or A CLKAB or CLKBA B or A SAB or SBA B or A DIR B or A OE B or A DIR B or A OE B or A VCC = 5 V, TA = 25°C VCC = 4.5 V to 5.5 V, TA = –55°C to 125°C MIN TYP MAX MIN 100 150 1.5 3.1 4.7 1.5 5.2 1.5 3.3 5.0 1.5 6 1.5 3.6 5.6 1.5 6.8 1.5 3.8 5.8 1.5 7 1.5 3.8 6.0 1.5 7.8 1.5 3.9 6.5 1.5 8.2 1.5 3.9 6.3 1.5 7.5 1.5 4 6.5 1.5 7.8 1.5 4.2 6.7 1.5 7.6 1.5 4.3 6.9 1.5 7.7 2 5.9 8.8 2 10.3 2 4.7 6.9 2 9.1 2 6 9 2 10.2 2 4.8 7.1 2 9.4 UNIT MAX 100 MHz ns ns ns ns ns ns ns switching characteristics over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (normal mode) (see Figure 15) SN74ABTH18646A PARAMETER fmax tPLH tPHL tPLH tPHL tPLH tPHL tPZH tPZL tPZH tPZL tPHZ tPLZ tPHZ tPLZ 30 FROM (INPUT) TO (OUTPUT) CLKAB or CLKBA A or B B or A CLKAB or CLKBA B or A SAB or SBA B or A DIR B or A OE B or A DIR B or A OE B or A POST OFFICE BOX 655303 VCC = 5 V, TA = 25°C VCC = 4.5 V to 5.5 V, TA = –40°C to 85°C MIN TYP 100 150 MAX MIN 1.5 3.1 4.7 1.5 5 1.5 3.3 5.0 1.5 5.4 1.5 3.6 5.6 1.5 5.9 1.5 3.8 5.8 1.5 6.1 1.5 3.8 6.0 1.5 6.6 1.5 3.9 6.5 1.5 6.8 1.5 3.9 6.3 1.5 7 1.5 4 6.5 1.5 7.2 1.5 4.2 6.7 1.5 7.4 1.5 4.3 6.9 1.5 7.6 2 5.9 8.8 2 10 2 4.7 6.9 2 8.1 MAX 100 MHz 2 6 9 2 9.7 2 4.8 7.1 2 7.6 • DALLAS, TEXAS 75265 UNIT ns ns ns ns ns ns ns SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 switching characteristics over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (test mode) (see Figure 15) SN54ABTH18646A PARAMETER FROM (INPUT) TO (OUTPUT) VCC = 5 V, TA = 25°C MIN fmax tPLH tPHL tPLH tPHL tPZH tPZL tPZH tPZL tPHZ tPLZ tPHZ tPLZ TCK TCK↓ A or B TCK↓ TDO TCK↓ A or B TCK↓ TDO TCK↓ A or B TCK↓ TDO TYP VCC = 4.5 V to 5.5 V, TA = –40°C to 85°C MAX MIN UNIT MAX 50 90 2.5 6.1 11 2.5 50 13.1 MHz 2.5 6.5 10.8 2.5 12.6 2 3.6 5.1 2 5.8 2 3.7 5.1 2 7 4 7.1 11.5 4 13.9 4 7.2 11.8 4 14.2 2 3.7 5.7 2 6.6 2 3.9 6.2 2 6.9 4 8.5 14.2 4 18 3 7.2 13.3 3 17.5 3 5.1 6.8 3 7.4 2.5 4 5.5 2.5 6.4 ns ns ns ns ns ns switching characteristics over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (test mode) (see Figure 15) SN74ABTH18646A PARAMETER fmax tPLH tPHL tPLH tPHL tPZH tPZL tPZH tPZL tPHZ tPLZ tPHZ tPLZ FROM (INPUT) TO (OUTPUT) TCK TCK↓ A or B TCK↓ TDO TCK↓ A or B TCK↓ TDO TCK↓ A or B TCK↓ TDO POST OFFICE BOX 655303 VCC = 5 V, TA = 25°C VCC = 4.5 V to 5.5 V, TA = –40°C to 85°C MIN TYP 50 90 2.5 6.1 11 2.5 13.1 2.5 6.5 10.8 2.5 12.4 2 3.6 5.1 2 5.6 2 3.7 5.1 2 5.6 4 7.1 11.5 4 13.4 4 7.2 11.8 4 13.6 2 3.7 5.7 2 6.6 2 3.9 6.2 2 6.9 4 8.5 13 4 15 3 7.2 13.3 3 15 3 5.1 6.8 3 7.2 2.5 4 5.5 2.5 6.3 • DALLAS, TEXAS 75265 MAX MIN UNIT MAX 50 MHz ns ns ns ns ns ns 31 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 recommended operating conditions SN54ABTH182646A VCC VIH Supply voltage VIL VI Low-level input voltage MAX MIN MAX 4.5 5.5 4.5 5.5 High-level input voltage 2 High level output current High-level IOL Low level output current Low-level ∆t/∆v Input transition rise or fall rate TA Operating free-air temperature 0 A port, TDO B port VCC –24 0 0.8 V V A port, TDO 48 64 B port 12 12 10 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 125 –40 V VCC –32 –12 –55 UNIT V –12 PRODUCT PREVIEW information concerns products in the formative or design phase of development. Characteristic data and other specifications are design goals. Texas Instruments reserves the right to change or discontinue these products without notice. 32 2 0.8 Input voltage IOH SN74ABTH182646A MIN mA mA 10 ns/V 85 °C SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) PARAMETER VIK A port, port TDO TEST CONDITIONS VCC = 4.5 V, II = –18 mA VCC = 4.5 V, IOH = –3 mA VCC = 5 V, IOH = –3 mA VCC = 4 4.5 5V VOH B port port TDO A port, VOL IOH = –24 mA IOH = –32 mA VCC = 4.5 V, IOH = –1 mA VCC = 5 V, IOH = –1 mA IOH = –3 mA VCC = 4 4.5 5V IOH = –12 mA IOL = 48 mA 5V VCC = 4 4.5 IOL = 64 mA MIN TA = 25°C TYP† MAX SN54ABTH182646A –1.2 –1.2 MIN MAX SN74ABTH182646A MIN –1.2 2.5 2.5 2.5 3 3 3 2 2 2* MAX 2 3.35 3.3 3.35 3.85 3.8 3.85 3.1 3 3.1 2.6* UNIT V V 2.6 0.55 0.55 0.55* IOL = 8 mA IOL = 12 mA 0.55 0.8 0.8 0.65 V B port VCC = 4 4.5 5V CLK, DIR, S, TCK VCC = 0 to 5.5 V, VI = VCC or GND ±1 ±1 ±1 A or B ports VCC = 5.5 V, VI = VCC or GND ±20 ±20 ±20 IIH OE, TDI, TMS VCC = 5.5 V, VI = VCC 10 10 10 µA IIL OE, TDI, TMS VCC = 5.5 V, VI = GND –40 –150 µA II(hold) I(h ld)‡ A or B ports 5V VCC = 4 4.5 VI = 0.8 V VI = 2 V 75 220 500 75 500 –75 –180 –500 –75 –500 IOZH TDO IOZL TDO IOZPU TDO VCC = 0 to 2.1 V, VO = 2.7 V or 0.5 V, OE = 0.8 V IOZPD TDO Ioff ICEX Outputs high II IO§ ∆ICC¶ 0.8 µA –150 –40 –150 –40 µA 10 10 10 µA –10 –10 –10 µA ±50 ±50 µA VCC = 2.1 V to 0, VO = 2.7 V or 0.5 V, OE = 0.8 V ±50 ±50 µA ±100 ±100 µA 50 µA A port, TDO VCC = 0, VI or VO ≤ 4.5 V VCC = 5.5 V, VO = 5.5 V VCC = 5.5 V, VO = 2.5 V –50 –110 –200 –50 –200 –50 –200 B port VCC = 5.5 V, VO = 2.5 V –25 –55 –100 –25 –100 –25 –100 1.7 2.2 2.2 2.2 23 27 27 27 1 2 2 2 Outputs high ICC VCC = 5.5 V, VO = 2.7 V, VCC = 5.5 V, VO = 0.5 V, 0.8* Outputs low Outputs disabled OE = 2 V OE = 2 V 50 VCC = 5.5 V, IO = 0, A or B ports orts VI = VCC or GND VCC = 5.5 V, One input at 3.4 V, Other inputs at VCC or GND 50 1.5 1.5 1.5 mA mA mA * On products compliant to MIL-PRF-38535, this parameter does not apply. † All typical values are at VCC = 5 V. ‡ The parameter II(hold) includes the off-state output leakage current. § Not more than one output should be tested at a time, and the duration of the test should not exceed one second. ¶ This is the increase in supply current for each input that is at the specified TTL voltage level rather than VCC or GND. PRODUCT PREVIEW information concerns products in the formative or design phase of development. Characteristic data and other specifications are design goals. Texas Instruments reserves the right to change or discontinue these products without notice. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 33 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 electrical characteristics over recommended operating free-air temperature range (unless otherwise noted) (continued) PARAMETER Ci Control inputs Cio A or B ports TEST CONDITIONS MIN TA = 25°C TYP† MAX VI = 2.5 V or 0.5 V VO = 2.5 V or 0.5 V Co TDO VO = 2.5 V or 0.5 V † All typical values are at VCC = 5 V. SN54ABTH182646A MIN MAX SN74ABTH182646A MIN MAX UNIT 5 pF 10 pF 8 pF timing requirements over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (normal mode) (see Figure 15)12 SN54ABTH182646A SN74ABTH182646A MIN MAX MIN MAX 100 0 100 UNIT fclock tw Clock frequency CLKAB or CLKBA 0 MHz Pulse duration CLKAB or CLKBA high or low 3 3 ns tsu th Setup time A before CLKAB↑ or B before CLKBA↑ 3 3 ns Hold time A after CLKAB↑ or B after CLKBA↑ 0.5 0.5 ns timing requirements over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (test mode) (see Figure 15) SN54ABTH182646A fclock tw tsu SN74ABTH182646A MIN MAX MIN MAX 50 0 50 Clock frequency TCK 0 Pulse duration TCK high or low 8 8 A, B, CLK, DIR, OE, or S before TCK↑ 6 6 4.5 4.5 Setup time TDI before TCK↑ TMS before TCK↑ A, B, CLK, DIR, OE, or S after TCK↑ 3 3 1.5 1.5 1 1 UNIT MHz ns ns th Hold time TMS after TCK↑ 1.5 1.5 td tr Delay time Power up to TCK↑ 50 50 ns Rise time VCC power up 1 1 µs TDI after TCK↑ PRODUCT PREVIEW information concerns products in the formative or design phase of development. Characteristic data and other specifications are design goals. Texas Instruments reserves the right to change or discontinue these products without notice. 34 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 ns SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 switching characteristics over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (normal mode) (see Figure 15)12 PARAMETER FROM (INPUT) TO (OUTPUT) fmax CLKAB or CLKBA tPLH tPHL A B tPLH tPHL B A tPLH tPHL CLKAB B tPLH tPHL CLKBA A tPLH tPHL SAB B tPLH tPHL SBA A tPZH tPZL DIR B or A tPZH tPZL OE B or A tPHZ tPLZ DIR B or A tPHZ tPLZ OE B or A VCC = 5 V, TA = 25°C SN54ABTH182646A MAX MIN MAX SN74ABTH182646A MIN TYP 100 150 1.5 3.5 5.1 1.5 5.8 1.5 5.3 1.5 4.1 5.8 1.5 6.4 1.5 6.1 1.5 3.1 4.7 1.5 5.2 1.5 5 1.5 3.3 5 1.5 5.6 1.5 5.4 1.5 4.3 6.2 1.5 7 1.5 6.5 1.5 4.9 7 1.5 8.1 1.5 7.4 1.5 3.6 5.2 1.5 6.2 1.5 5.9 1.5 3.8 5.5 1.5 6.5 1.5 6.1 1.5 4.4 6.9 1.5 7.6 1.5 7.2 1.5 4.8 7.4 1.5 8.3 1.5 7.8 1.5 3.8 5.6 1.5 6.8 1.5 6.6 1.5 3.9 6 1.5 7.2 1.5 6.8 1.5 3.9 6.3 1.5 7.5 1.5 7 1.5 4 6.5 1.5 7.7 1.5 7.2 1.5 4.2 6.7 1.5 8.1 1.5 7.4 1.5 4.3 6.9 1.5 8.4 1.5 7.6 2 5.9 8.8 2 10.3 2 10 2 4.7 6.9 2 8.7 2 8.1 100 MIN UNIT MAX 100 MHz 2 6 9 2 10.5 2 9.7 2 4.8 7.1 2 8.7 2 7.6 ns ns ns ns ns ns ns ns ns ns switching characteristics over recommended ranges of supply voltage and operating free-air temperature (unless otherwise noted) (test mode) (see Figure 15) PARAMETER fmax tPLH tPHL tPLH tPHL tPZH tPZL tPZH tPZL tPHZ tPLZ tPHZ tPLZ FROM (INPUT) TO (OUTPUT) TCK TCK↓ A or B TCK↓ TDO TCK↓ A or B TCK↓ TDO TCK↓ A or B TCK↓ TDO VCC = 5 V, TA = 25°C SN54ABTH182646A MAX MIN MAX SN74ABTH182646A MIN TYP 50 90 2.5 6.1 11 2.5 14.5 2.5 13.1 2.5 6.5 10.8 2.5 14 2.5 12.4 2 3.6 5.1 2 7 2 5.6 2 3.7 5.1 2 7 2 5.6 4 7.1 11.5 4 14.5 4 13.4 4 7.2 11.8 4 15 4 13.6 2 3.7 5.7 2 7.5 2 6.6 2 3.9 6.2 2 8 2 6.9 4 8.5 13 4 18 4 15 3 7.2 13.3 3 17.5 3 15 3 5.1 6.8 3 8 3 7.2 2.5 4 5.5 2.5 8 2.5 6.3 50 MIN UNIT MAX 50 MHz ns ns ns ns ns ns PRODUCT PREVIEW information concerns products in the formative or design phase of development. Characteristic data and other specifications are design goals. Texas Instruments reserves the right to change or discontinue these products without notice. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 35 SN54ABTH18646A, SN54ABTH182646A, SN74ABTH18646A, SN74ABTH182646A SCAN TEST DEVICES WITH 18-BIT TRANSCEIVERS AND REGISTERS SCBS166D – AUGUST 1993 – REVISED JULY 1996 PARAMETER MEASUREMENT INFORMATION 7V S1 500 Ω From Output Under Test Open GND CL = 50 pF (see Note A) 500 Ω TEST S1 tPLH/tPHL tPLZ/tPZL tPHZ/tPZH Open 7V Open LOAD CIRCUIT 3V 1.5 V Timing Input 0V tw tsu 3V Input 1.5 V 1.5 V th 3V Data Input 1.5 V 1.5 V 0V 0V VOLTAGE WAVEFORMS PULSE DURATION VOLTAGE WAVEFORMS SETUP AND HOLD TIMES 3V Input 1.5 V 1.5 V 0V 1.5 V Output 1.5 V VOH VOL VOH Output 1.5 V 1.5 V VOL VOLTAGE WAVEFORMS PROPAGATION DELAY TIMES INVERTING AND NONINVERTING OUTPUTS 1.5 V 0V tPLZ Output Waveform 1 S1 at 7 V (see Note B) tPLH tPHL 1.5 V tPZL tPHL tPLH 3V Output Control Output Waveform 2 S1 at Open (see Note B) 1.5 V tPZH 3.5 V VOL + 0.3 V VOL tPHZ 1.5 V VOH – 0.3 V VOH [0V VOLTAGE WAVEFORMS ENABLE AND DISABLE TIMES LOW- AND HIGH-LEVEL ENABLING NOTES: A. CL includes probe and jig capacitance. B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control. Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control. C. All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, ZO = 50 Ω, tr ≤ 2.5 ns, tf ≤ 2.5 ns. D. The outputs are measured one at a time with one transition per measurement. Figure 15. Load Circuit and Voltage Waveforms 36 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 IMPORTANT NOTICE Texas Instruments and its subsidiaries (TI) reserve the right to make changes to their products or to discontinue any product or service without notice, and advise customers to obtain the latest version of relevant information to verify, before placing orders, that information being relied on is current and complete. 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