Revised December 2000 GTLP8T306 8-Bit LVTTL/GTLP Bus Transceiver General Description Features The GTLP8T306 is an 8-bit bus transceiver that provides LVTTL to GTLP signal level translation. The device provides a high speed interface between cards operating at LVTTL logic levels and a backplane operating at GTLP logic levels. High speed backplane operation is a direct result of GTLP’s reduced output swing (<1V), reduced input threshold levels and output edge rate control. The edge rate control minimizes bus settling time. GTLP is a Fairchild Semiconductor derivative of the Gunning Transceiver logic (GTL) JEDEC standard JESD8-3. ■ Bidirectional interface between GTLP and LVTTL logic levels Fairchild’s GTLP has internal output edge-rate control and is process, voltage, and temperature (PVT) compensated. Its function is similar to BTL and GTL but with different output levels and receiver thresholds. The GTLP output LOW level is typically less than 0.5V, the output HIGH level is 1.5V and the receiver threshold is 1.0V. ■ Designed with edge rate control circuitry to reduce output noise on the GTLP port ■ VREF pin provides external supply reference voltage for receiver threshold adjustibility ■ Special PVT Compensation circuitry to provide consistent performance over variations of process, supply voltage and temperature ■ TTL compatible driver and control inputs ■ Designed using Fairchild advanced CMOS technology ■ Bushold data inputs on A port to eliminate the need for external pull-up resistors for unused inputs ■ Power up/down and power off high impedance for live insertion ■ 5V over voltage tolerance on LVTTL ports ■ Open drain on GTLP to support wired-or connection ■ Flow through pinout optimizes PCB layout ■ A Port source/sink −24mA/+24mA ■ B Port sink +50mA Ordering Code: Order Number Package Number Package Description GTLP8T306MTC MTC24 24-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide Devices also available in Tape and Reel. Specify by appending the suffix letter “X” to the ordering code. Connection Diagram © 2000 Fairchild Semiconductor Corporation DS500051 www.fairchildsemi.com GTLP8T306 8-Bit LVTTL/GTLP Bus Transceiver September 1997 GTLP8T306 Pin Descriptions Pin Names Truth Table Description Inputs Output OE Output Enable (Active LOW) T/R OE T/R Transmit/Receive Input H X HIGH Z on Bus A and Bus B A0–A7 Side A Inputs or 3-STATE Outputs L L Bus B Data to Bus A B0–B7 Side B Inputs or 3-STATE Outputs L H Bus A Data to Bus B VREF GTLP Reference Voltage Functional Description The GTLP8T306 is an 8-bit transceiver providing the standard 245 functionality that supports both GTL and GTLP signal levels. Data polarity is non-inverting and the data flow direction is controlled by the T/R pin. The outputs are enabled to allow data through the device when OE is LOW otherwise both the A and B ports are placed in a HIGH impedance state. Logic Diagram www.fairchildsemi.com 2 Supply Voltage (VCC) −0.5V to 7.0V DC Input Voltage (VI) −0.5V to +7.0V Recommended Operating Conditions (Note 3) 3.15V to 3.45V Supply Voltage VCC DC Output Voltage (VO) Bus Termination Voltage (VTT) −0.5V to +7.0V Outputs 3-STATE −0.5V to 7.0V Outputs Active (Note 2) DC Output Sink Current into A-Port, IOL 48 mA 1.35V to 1.65V GTL 1.14V to 1.26V Input Voltage (VI) on A-Port DC Output Source Current from and control pins A Port IOH 0V to 5.5V −48 mA HIGH Level Output Current (IOH) 100 mA LOW Level Output Current (IOL) DC Output Sink Current into B-Port −24 mA A Port in the LOW State, IOL DC Input Diode Current (IIK) +24 mA A Port VI < 0V −50 mA +50 mA B Port DC Output Diode Current (IOK) −40°C to +85°C Operating Temperature (TA) VO < 0V −50 mA VO > VCC +50 mA ESD Rating >2000V Storage Temperature (TSTG) GTLP Note 1: The Absolute Maximum Ratings are those values beyond which the safety of the device cannot be guaranteed. The device should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed at the absolute maximum rating. The “Recommended Operating Conditions” table will define the conditions for actual device operation. −65°C to +150°C Note 2: IO Absolute Maximum Rating must be observed. Note 3: Unused inputs must be held HIGH or LOW. DC Electrical Characteristics Over Recommended Operating Free-Air Temperature Range, VREF = 1.0V (unless otherwise noted). Symbol VIH VIL Min Test Conditions Typ B Port VREF +0.05 Others 2.0 B Port 0.0 GTLP 1.0 GTL 0.8 VIK VOH VOL A Port A Port B Port II A Port Control Pins B Port Units VTT V VREF −0.05 V 0.8 V V Others VREF Max (Note 4) VCC = 3.15V II = −18 mA VCC = Min to Max (Note 5) IOH = −100 µA VCC −0.2 VCC = 3.15V IOH = −12 mA 2.4 IOH = −24 mA 2.0 V V −1.2 V VCC = Min to Max (Note 5) IOL = 100 µA 0.2 VCC = 3.15V IOL = 24 mA 0.5 VCC = 3.15V IOL = 40 mA 0.4 IOL = 50 mA 0.55 VCC = 3.45V VCC = 3.45V VCC = 3.45V VI = 5.5V 20 VI = 0V −20 VI = 5.5V 5 VI = 0V −5 VI = VTT 5 VI = 0 −5 IOFF A Port VCC = 0 VI or VO = 0 to 4.5V II (Hold) A Port VCC = 3.15V VI = 0.8V 75 VI = 2.0V −20 IOZH A Port VCC = 3.45V VO = 3.45V A Port VCC = 3.45V VO = 0 −20 B Port VCC = 3.45V VO = 0.55 −5 VO = 1.5V B Port IOZL 3 V 100 V V µA µA µA µA µA 20 5 µA µA www.fairchildsemi.com GTLP8T306 Absolute Maximum Ratings(Note 1) GTLP8T306 DC Electrical Characteristics Symbol ICC A or B Ports (Continued) Min Test Conditions VCC = 3.45V Typ Max Outputs HIGH 7 18 Outputs LOW 8 20 IO = 0 VI = V CC or GND Outputs Disabled 8 20 ICC A Port and VCC = 3.45V One Input at VCC–0.6V 0 1 (Note 6) Control Pins A or Control Inputs at VCC or GND CIN Units (Note 4) Control Pins VI = VCC or 0 5 A Port VI = VCC or 0 7 B Port VI = VCC or 0 9 mA mA pF Note 4: All typical values are VCC = 3.3V and T A= 25°C. Note 5: For conditions shown as Min, use the appropriate value specified under recommended operating conditions. Note 6: This is the increase in supply current for each input that is at the specified LVTTL voltage level rather than VCC or GND. AC Electrical Characteristics Over recommended range of supply voltage and operating free air-temperature, VREF = 1.0V (unless otherwise noted). CL = 30 pF for B Port and CL = 50 pF for A Port. Min Symbol From (Input) Typ Max Units To (Output) (Note 7) tPLH An Bn tPLH 1.0 4.0 7.5 1.0 5.1 7.5 1.0 5.8 8.3 1.0 4.9 8.3 ns tPHL Bn An ns tPHL tRISE Transition Time, B Outputs (20% to 80%) 2.6 ns tFALL Transition Time, B Outputs (20% to 80%) 2.6 ns tRISE Transition Time, A Outputs (10% to 90%) 2.5 ns tFALL Transition Time, A Outputs (10% to 90%) 2.5 ns tPZH, tPZL OE An tPLH OE Bn 4.5 9.5 1.0 4.9 9.5 1.0 5.4 9.5 1.0 6.0 9.5 ns tPHL Note 7: All typical values are at VCC = 3.3V and TA = 25°C. www.fairchildsemi.com 1.0 ns tPHZ, tPLZ 4 Test Circuit for A Outputs Test Circuit for B Outputs Voltage Waveforms Pulse Duration (VM = VCC/2 for A Port and 1.0 for B-Port) Voltage Waveforms Enable and Disable Times A Port Voltage Waveforms Propagation Delay and Setup and Hold Times (VM = VCC/2 for A Port and 1.0 for B Port) Note A: CL includes probes and Jig capacitance. Note B: For B Port, CL = 30 pF is used for worst case. 5 www.fairchildsemi.com GTLP8T306 Test Circuit and Timing Waveforms GTLP8T306 8-Bit LVTTL/GTLP Bus Transceiver Physical Dimensions inches (millimeters) unless otherwise noted 24-Lead Thin Shrink Small Outline Package (TSSOP), JEDEC MO-153, 4.4mm Wide Package Number MTC24 Fairchild does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and Fairchild reserves the right at any time without notice to change said circuitry and specifications. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. www.fairchildsemi.com www.fairchildsemi.com 6