ML65F16245

June 1998 PRELIMINARY ML65F16245* 16-Bit Bidirectional Transceiver with 3-State Outputs GENERAL DESCRIPTION The ML65F16245 is a BiCMOS, non-inverting 16-bit transceiver with 3-state outputs. This device was specifically designed for high speed bus applications. Its 16 channels support propagation delay of 2ns maximum, and fast output enable and disable times of 5ns or less to minimize datapath delay. This device is designed to minimize undershoot, overshoot, and ground bounce to decrease noise delays. These transceivers implement a unique digital and analog implementation to eliminate the delays and noise inherent in traditional digital designs. The device offers a new method for quickly charging up a bus load capacitor to minimize bus settling times, or FastBus™ Charge. FastBus Charge is a transition current, (specified as IDYNAMIC) that injects between 60 to 200mA (depending on output load) of current during the rise time and fall time. This current is used to reduce the amount of time it takes to charge up a heavily-capacitive loaded bus, effectively reducing the bus settling times, and improving data/clock margins in tight timing budgets. Micro Linear’s solution is intended for applications for critical bus timing designs that include minimizing device propagation delay, bus settling time, and time delays due to noise. Applications include; high speed memory arrays, bus or backplane isolation, bus to bus bridging, and sub-2ns propagation delay schemes. The ML65F16245 follows the pinout and functionality of the industry standard 2.7V to 3.6V-logic families. FEATURES s Low propagation delays — 2ns maximum for 3.3V, 2.5ns maximum for 2.7V Fast output enable/disable times of 5ns maximum FastBus Charge current to minimize the bus settling time during active capacitive loading 2.7V to 3.6V a VCC supply operation; LV-TTL compatible input and output levels with 3-state capability Industry standard pinout compatible to FCT, ALV, LCX, LVT, and other low voltage logic families ESD protection exceeds 2000V Full output swing for increased noise margin Undershoot and overshoot protection to 400mV typically Low ground bounce design s s s s s s s s *This Part Is End Of Life As Of August 1, 2000 BLOCK DIAGRAM VCC OEAB Bi Bi Ai DIR OE OEBA GND i=0 to 15 1 ML65F16245 PIN CONFIGURATION ML65F16245 48-Pin SSOP (R48) 48-Pin TSSOP (T48) 1DIR 1B0 1B1 GND 1B2 1B3 VCC 1B4 1B5 GND 1B6 1B7 2B0 2B1 GND 2B2 2B3 VCC 2B4 2B5 GND 2B6 2B7 2DIR 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 1OE 1A0 1A1 GND 1A2 1A3 VCC 1A4 1A5 GND 1A6 1A7 2A0 2A1 GND 2A2 2A3 VCC 2A4 2A5 GND 2A6 2A7 2OE TOP VIEW FUNCTION TABLE (Each 8-bit section) OE H L L i = 0 to 7 DIR X L H Ai Z Output Input Bi Z Input Output FUNCTION Disable Bus B to Bus A Bus A to Bus B L = Logic Low, H = Logic High, X = Don’t Care, Z = High Impedance 2 ML65F16245 PIN DESCRIPTION PIN NAME FUNCTION PIN NAME FUNCTION 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 1DIR 1B0 1B1 GND 1B2 1B3 VCC 1B4 1B5 GND 1B6 1B7 2B0 2B1 GND 2B2 2B3 VCC 2B4 2B5 GND 2B6 2B7 2DIR Direction Select Data Bus 1B Data Bus 1B Signal Ground Data Bus 1B Data Bus 1B 2.7V to 3.6V Supply Data Bus 1B Data Bus 1B Signal Ground Data Bus 1B Data Bus 1B Data Bus 2B Data Bus 2B Signal Ground Data Bus 2B Data Bus 2B 2.7V to 3.6V Supply Data Bus 2B Data Bus 2B Signal Ground Data Bus 2B Data Bus 2B Direction Select 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 2OE 2A7 2A6 GND 2A5 2A4 VCC 2A3 2A2 GND 2A1 2A0 1A7 1A6 GND 1A5 1A4 VCC 1A3 1A2 GND 1A1 1A0 1OE Output Enable Data Bus 2A Data Bus 2A Signal Ground Data Bus 2A Data Bus 2A 2.7V to 3.6V Supply Data Bus 2A Data Bus 2A Signal Ground Data Bus 2A Data Bus 2A Data Bus 1A Data Bus 1A Signal Ground Data Bus 1A Data Bus 1A 2.7V to 3.6V Supply Data Bus 1A Data Bus 1A Signal Ground Data Bus 1A Data Bus 1A Output Enable 3 ML65F16245 ABSOLUTE MAXIMUM RATINGS Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. VCC ............................................................................. 7V DC Input Voltage ............................. –0.3V to VCC + 0.3V AC Input Voltage (PW < 20ns) ................................ –3.0V DC Output Voltage ...................................–0.3V to 7VDC Output Current, Source or Sink ............................. 180mA Storage Temperature Range ..................... –65°C to 150°C Junction Temperature .............................................. 150°C Lead Temperature (Soldering, 10sec) ...................... 150°C Thermal Impedance (qJA) ..................................... 76°C/W OPERATING CONDITIONS Temperature Range ....................................... 0°C to 70°C VIN Operating Range ...................................2.7V to 3.6V ELECTRICAL CHARACTERISTICS Unless otherwise specified, VIN = 3.3V, TA = Operating Temperature Range (Note 1). SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS AC ELECTRICAL CHARACTERISTICS (CLOAD = 50pF) tPHL, tPLH Propagation Delay Ai to/from Bi 3.3V 2.7V tOE Output Enable Time OE to Ai/Bi 3.3V 2.7V DIR to Ai/Bi 3.3V 2.7V tOD Output Disable Time OE to Ai/Bi 3.3V 2.7V DIR to Ai/Bi 3.3V 2.7V TOS CIN Output-to-Output Skew Input Capacitance 8 1.35 1.25 1.7 1.9 2 2.5 5 6 5 6 5 6 5 6 300 ns ns ns ns ns ns ns ns ns ns ps pF DC ELECTRICAL CHARACTERISTICS (CLOAD = 50pF, RLOAD = Open) VIH VIL IIH IIL IHI-Z V IC Input High Voltage Input Low Voltage Input High Current Input Low Current Three-State Output Current Input Clamp Voltage Logic high Logic low Per pin, VIN = 3V Per pin, VIN = 0V VCC = 3.6V, 0 < VIN < VCC VCC = 3.6V, IIN = 18mA Low to high transitions High to low transitions VCC = 3.6V VCC = 2.7V VOL I CC Output Low Voltage Quiescent Power Supply Current VCC = 3.6V and 2.7V VCC = 3.6V, f = 0Hz, inputs = VCC or 0V 2.4 2.25 –0.7 80 80 3.4 2.35 0.6 3 2.0 0.8 300 300 5 –0.2 V V µA µA µA V mA mA V V V µA I DYNAMIC Dynamic Transition Current (FastBus Charge) VOH Output High Voltage Note 1: Limits are guaranteed by 100% testing, sampling, or correlation with worst-case test conditions. 4 ML65F16245 100 0 –20 80 –40 –60 IOL (mA) IOH (mA) 0 0.4 0.8 1.2 1.6 2 60 –80 –100 –120 –140 40 20 –160 –180 0 –200 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 VOL (V) VOH (V) Figure 1a. Typical VOL vs. IOL for 3.3V VCC. One Buffer Output 3.0 Figure 1b. Typical VOH vs. IOH for 3.3V VCC. One Buffer Output 3.0 2.5 VCC = 2.7V 2.0 tPHL (ns) 2.5 VCC = 2.7V 2.0 VCC = 3.3V tPLH (ns) 1.5 1.5 VCC = 3.3V 1.0 1.0 0.5 0.5 0 0 25 50 75 0 0 25 50 75 LOAD CAPACITANCE (pF) LOAD CAPACITANCE (pF) Figure 2a. Propagation Delay vs. Load Capacitance: 3.3V, 50MHZ 60 Figure 2b. Propagation Delay vs. Load Capacitance: 2.7V, 50MHZ 60 50 75pF 40 ICC (mA) ICC (mA) 50 75pF 40 30 50pF 30 50pF 20 30pF 10 20 10 30pF 0 0 20 40 60 80 100 0 0 20 40 60 80 100 FREQUENCY (MHz) FREQUENCY (MHz) Figure 3a. ICC vs. Frequency: VCC = VIN = 3.3V. One Buffer Output Figure 3b. ICC vs. Frequency: VCC = VIN = 2.7V. One Buffer Output 5 ML65F16245 FUNCTIONAL DESCRIPTION 1DIR 1OE 1OEAB 1B0 1OEBA 1B1 1A1 1A0 2DIR 2OE 2OEAB 2B0 2OEBA 2B1 2A1 2A0 1B2 1A2 2B2 2A2 1B3 1A3 2B3 2A3 1B4 1A4 2B4 2A4 1B5 1A5 2B5 2A5 1B6 1A6 2B6 2A6 1B7 1A7 2B7 2A7 Figure 4. Logic Diagram 1A0 1A1 1A2 1A3 1A4 1A5 1A6 1A7 2A0 2A1 2A2 2A3 2A4 2A5 2A6 2A7 1OE 2OE 1DIR 2DIR 1B0 1B1 1B2 1B3 1B4 1B5 1B6 1B7 2B0 2B1 2B2 2B3 2B4 2B5 2B6 2B7 Figure 5. Logic Symbol 6 ML65F16245 ARCHITECTURAL DESCRIPTION The ML65F16245 is a 16-bit (dual-octal) non-inverting bus transceiver with 3-state outputs designed for 2.7V to 3.6V VCC operation. This device is designed for asynchronous communication between data buses. The ML65F16245 can be used as two 8-bit transceivers or as one 16-bit transceiver and can be designated as Port-A bus and Port-B bus. The Direction and Output Enable controls are designed to operate these configurations. The direction control pin (iDIR) controls the direction of the data flow. The output enable pin (1OE, 2OE) overrides the direction control and disables both ports. Until now, these transceivers were typically implemented in CMOS logic and made to be TTL compatible by sizing the input devices appropriately. In order to buffer large capacitances with CMOS logic, it is necessary to cascade an even number of inverters, each successive inverter larger than the preceding, eventually leading to an inverter that will drive the required load capacitance at the required frequency. Each inverter stage represents an additional delay in the gating process because in order for a single gate to switch, the input must slew more than half of the supply voltage. The best of these 16-bit CMOS buffers has managed to drive 50pF load capacitance with a delay of 3ns. Micro Linear has produced a 16-bit transceiver with a delay less than 2ns (at 3.3V) by using a unique circuit architecture that does not require cascade logic gates. The basic architecture of the ML65F16245 is shown in Figure 6. In this circuit, there are two paths to the output. One path sources current to the load capacitance where the signal is asserted, and the other path sinks current from the output when the signal is negated. The assertion path is the Darlington pair consisting of transistors Q1 and Q2. The effect of transistor Q1 is to increase the current gain through the stage from input to output, to increase the input resistance and to reduce input capacitance. During the transition state (the input from low-to-high) the output transistor Q2 sources large amount of current to quickly charge up a highly capacitive load which in effect reduces the bus settling time. This current is specified as IDYNAMIC. The negation path is also the Darlington pair consisting of transistor Q3 and transistor Q4. With M1 connecting to the input of the Darlington pair, Transistor Q4 then sinks a large amount of current during the input transition from high-to-low. Inverter X2 is a helpful buffer that not only drives the output toward the upper rail but also pulls the output to the lower rail. There are a number of MOSFETs not shown in Figure 6. These MOSFETs are used to 3-state the buffers. VCC OE Q1 Q2 X1 IN X2 OUT M1 Q3 Q4 Figure 6. One Buffer Cell of the ML65F16245 7 ML65F16245 CIRCUITS AND WAVE FORMS VCC = 3V ML65F16245 DUT VIN 50pF IOUT VOUT 1.5V INPUT tPLH 1.5V OUTPUT tPHL 0V 0V 3V tRISE AND tFALL INPUT = 2ns Figure 7. Test Circuits for All Outputs Figure 8. Propagation Delay ENABLE CONTROL INPUT tOE OUTPUT LOW tOE OUTPUT HIGH DISABLE VCC = 3V 1.5V tOD 3V OUTPUT1 1.5V INPUT 1.5V VOL + 0.3V VOL VOH VOH – 0.3V 0V tOD tOS OUTPUTi i = 1 to 16 1.5V Figure 9. Enable and Disable Times Figure 10. Output Skew 8 ML65F16245 PHYSICAL DIMENSIONS inches (millimeters) Package: R48 48-Pin SSOP 0.620 - 0.630 (15.75 - 16.00) 48 PIN 1 ID 0.291 - 0.301 0.402 - 0.410 (7.39 - 7.65) (10.21 - 10.41) 1 0.015 - 0.025 (0.38 - 0.64) (4 PLACES) 0.025 BSC (0.63 BSC) 0.094 - 0.110 (2.39 - 2.79) 0º - 8º 0.088 - 0.092 (2.24 - 2.34) 0.006 - 0.014 (0.15 - 0.36) SEATING PLANE 0.008 - 0.016 (0.20 - 0.41) 0.024 - 0.040 (0.61 - 1.02) 0.005 - 0.010 (0.13 - 0.26) Package: T48 48-Pin TSSOP 0.487 - 0.497 (12.37 - 12.63) 0.236 - 0.244 (6.00 - 6.20) 0.319 BSC (8.1 BSC) PIN 1 ID 0.020 BSC (0.50 BSC) 0.047 MAX (1.20 MAX) 0º - 8º 0.031 - 0.039 (0.80 - 1.00) 0.007 - 0.011 (0.17 - 0.27) SEATING PLANE 0.002 - 0.006 (0.05 - 0.15) 0.020 - 0.028 (0.50 - 0.70) 0.004 - 0.008 (0.10 - 0.20) 9 ML65F16245 ORDERING INFORMATION PART NUMBER ML65F16245CR (Obsolete) ML65F16245CT (EOL) TEMPERATURE RANGE 0°C to 70°C 0°C to 70°C PACKAGE 48-Pin SSOP (R48) 48-Pin TSSOP (T48) © Micro Linear 1998. is a registered trademark of Micro Linear Corporation. All other trademarks are the property of their respective owners. Products described herein may be covered by one or more of the following U.S. patents: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; 5,546,017; 5,559,470; 5,565,761; 5,592,128; 5,594,376; 5,652,479; 5,661,427; 5,663,874; 5,672,959; 5,689,167; 5,714,897; 5,717,798; 5,742,151; 5,747,977; 5,754,012; 5,757,174; 5,767,653;. Japan: 2,598,946; 2,619,299; 2,704,176. Other patents are pending. Micro Linear reserves the right to make changes to any product herein to improve reliability, function or design. Micro Linear does not assume any liability arising out of the application or use of any product described herein, neither does it convey any license under its patent right nor the rights of others. The circuits contained in this data sheet are offered as possible applications only. Micro Linear makes no warranties or representations as to whether the illustrated circuits infringe any intellectual property rights of others, and will accept no responsibility or liability for use of any application herein. The customer is urged to consult with appropriate legal counsel before deciding on a particular application. 2092 Concourse Drive San Jose, CA 95131 Tel: (408) 433-5200 Fax: (408) 432-0295 www.microlinear.com DS65F16245-01 10