LSI/CSI LS7083 LS7084 UL ® A3800 LSI Computer Systems, Inc. 1235 Walt Whitman Road, Melville, NY 11747 (631) 271-0400 FAX (631) 271-0405 QUADRATURE CLOCK CONVERTER PIN ASSIGNMENT - TOP VIEW 2 V SS (-V) 3 A 4 nt co D is RBIAS (Pin 1) Input for external component connection. A resistor connected between this input and VSS adjusts the output clock pulse width (Tow). For proper operation, the output clock pulse width must be less than or equal to the A, B pulse separation (TOW ≤ TPS). VDD (Pin 2) Supply Voltage positive terminal. VSS (Pin 3) Supply Voltage negative terminal. A (Pin 4) Quadrature Clock Input A. This input has a filter circuit to validate input logic level and eliminate encoder dither. B (Pin 5) Quadrature Clock Input B. This input has a filter circuit identical to input A. x4/x1 (Pin 6) This input selects between x1 and x4 modes of operation. A highlevel selects x4 mode and a low-level selects the x1 mode. In x4 mode, an output pulse is generated for every transition at either A or B input. In x1 mode, an output pulse is generated in one combined A/B input cycle. (See Figure 2.) RBIAS 1 V DD (+V) 2 V SS (-V) 3 A 4 LS7084 in u ed V DD (+V ) LSI DESCRIPTION The LS7083 and LS7084 are CMOS quadrature clock converters. Quadrature clocks derived from optical or magnetic encoders, when applied to the A and B inputs of the LS7083 or LS7084, are converted to strings of Up Clocks and Down Clocks (LS7083) or to a Clock and an Up/Down direction control (LS7084). These outputs can be interfaced directly with standard Up/Down counters for direction and position sensing of the en- 7083/84-011309-1 1 LS7083 Applications: • Interface incremental encoders to Up / Down Counters (See Figure 6A and Figure 6B) • Interface rotary encoders to Digital Potentiometers (See Figure 7) RBIAS LSI FEATURES: • x1 and x4 mode selection • Up to 16MHz output clock frequency • Programmable output clock pulse width • On-chip filtering of inputs for optical or magnetic encoder applications. • TTL and CMOS compatible I/Os • +4.5V to +10V operation (VDD - VSS) • LS7083, LS7084 (DIP); LS7083-S, LS7084-S (SOIC) - See Figure 1 INPUT/OUTPUT DESCRIPTION: January 2009 8 UPCK 7 DNCK 6 x4/x1 5 B 8 CLK 7 UP/DN 6 x4/x1 5 B FIGURE 1 LS7083 - DNCK (Pin 7) In LS7083, this is the DOWN Clock Output. This output consists of low-going pulses generated when A input lags the B input. LS7084 - UP/DN (Pin 7) In LS7084, this is the count direction indication output. When A input leads the B input, the UP/DN output goes high indicating that the count direction is UP. When A input lags the B input, UP/DN output goes low, indicating that the count direction is DOWN. LS7083 - UPCK (Pin 8) In LS7083, this is the UP Clock output. This output consists of lowgoing pulses generated when A input leads the B input. LS7084N - CLK (Pin 8) In LS7084, this is the combined UP Clock and DOWN Clock output. The count direction at any instant is indicated by the UP/DN output (Pin 7). NOTE: For the LS7084, the timing of CLK and UP/DN requires that the counter interfacing with LS7084 counts on the rising edge of the CLK pulses. ABSOLUTE MAXIMUM RATINGS: PARAMETER DC Supply Voltage Voltage at any input Operating temperature Storage temperature SYMBOL VDD - VSS VIN TA TSTG VALUE 11.0 VSS - 0.3 to VDD + 0.3 0 to +70 -55 to +150 UNITS V V °C °C DC ELECTRICAL CHARACTERISTICS: (All voltages referenced to VSS, TA = 0oC to 70oC.) SYMBOL VDD IDD MIN 4.5 - MAX 10.0 6.0 x4/x1 Logic Low A, B Logic Low VIL VIL - x4/x1Logic High A, B Logic High VIH VIH 0.7VDD 3.1 5.0 5.6 - ALL OUTPUTS: Sink Current VOL = 0.4V IOL 1.75 5.0 5.7 - IOH 1.0 2.5 3.0 - 0.3VDD 0.6 1.0 1.1 TRANSIENT CHARACTERISTICS: (TA = 0° C to 70° C) CONDITION VDD = 10V, All input frequencies = 0Hz RBIAS = 2MΩ V V V V VDD = 4.5V VDD = 9V VDD = 10V V V V V VDD = 4.5V VDD = 9V VDD = 10V mA mA mA VDD = 4.5V VDD = 9V VDD = 10V mA mA mA VDD = 4.5V VDD = 9V VDD = 10V in u SYMBOL MIN TVD - 85 100 160 ns ns ns VDD = 10V VDD = 9V VDD = 4.5V TPW TVD + TOW Infinite ns - A to B or B to A Phase Delay TPS TOW Infinite ns - A, B frequency fA, B - 1 2TPW Hz - Input to Output Delay TDS - 120 150 235 ns ns ns VDD = 10V VDD = 9V VDD = 4.5V Includes input validation delay Output Clock Pulse Width TOW 50 - ns See Fig. 4 & 5 7083/84-121508-2 D A, B inputs: Pulse Width is PARAMETER A, B inputs: Validation Delay co nt Source Current VOH = VDD - 0.5V UNITS V µA ed PARAMETER Supply voltage Supply current MAX UNITS CONDITION TPW A B TPS TDS UPCK (x1/7083) TOW DNCK (x1/7083) UPCK (x4/7083) DNCK (x4/7083) CLK (x1/7084) ed CLK (x4/7084) TDS UP/DN (7084) 1 CURRENT MIRROR nt RBIAS in u FIGURE 2. LS7083 / LS7084 INPUT / OUTPUT TIMING DIAGRAM FILTER co DUAL ONE-SHOT DUAL ONE-SHOT D B 5 FILTER is A 4 x4/x1 CLOCK AND DIRECTION DECODE x4 CLOCK 8 x1 CLOCK UP/DN UPCK or CLK MUX 7 DNCK or UP/DN 6 V DD 2 +V V SS 3 -V FIGURE 3. LS7083/LS7084 BLOCK DIAGRAM The information included herein is believed to be accurate and reliable. However, LSI Computer Systems, Inc. assumes no responsibilities for inaccuracies, nor for any infringements of patent rights of others which may result from its use. 7083/84-121608-3 1500 1250 V DD = 5V 25 OUTPUT CLOCK PULSE WIDTH, Tow, µs V DD = 9V 1000 OUTPUT CLOCK PULSE WIDTH, Tow, ns 30 V DD = 5V V DD = 10V 750 500 250 100 200 300 400 20 V DD = 9V 15 V DD = 10V 10 5 500 2 6 4 Figure 4. Tow vs RBIAS, k 8 12 10 Figure 5. Tow vs RBIAS, M +V +V 5 1 V DD UPCK A B DNCK RBIAS RB VDD 8 5 CK-UP 40193 LS7083 7 4 CK-DN V SS 3 6 in u B CLOCK x4/x1 16 ENCODER B CLOCK V SS 1M ROTARY ENCODER 10k CLK VDD U/D V SS X4/X1 4 A B 1 UP/DN RBIAS 15 7 10 CK 4516 UP/DN V SS 3 V SS 8 DIGITAL POTENTIOMETER 8 1 CLK 7 2 6 3 A1 B1 6 5 4 GND W1 5 U/D LS7084 0.01uF 7083/84-011209-4 5 B 8 *See NOTE at bottom right of Page 1 1 RBIAS 2 10k Part Number: RE11CT-V1Y12-EF2CS LS7084 A1 3 GND A CLK V DD +5V B A 4 16 2 VDD FIGURE 6B*. TYPICAL APPLICATION FOR LS7084 WITH X4/X1 MODE SELETION is D 10k x4/x1 RB 8 FIGURE 6A. TYPICAL APPLICATION FOR LS7083 IN x4 MODE 10k A CLOCK nt 4 2 +V +V R co ENCODER A CLOCK 6 ed MODE SELECT V DD CS AD5220 0.01uF FIGURE 7. Rotary Encoder Control of Digital Potentiometer 8 7 B1 W1