IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 PRODUCT FEATURES PRODUCT DESCRIPTION þ Generates CPU Clock Signals for Microprocessor Systems þ Reduces Measured EMI by 10 dB nominal þ 4V to 6V Operating Supply Range þ Supports CPUs from all major manufacturers þ Wide Range of Selectable Output Frequencies including 40, 30, 25, and 16.7 MHz. þ Single, Low Cost Crystal used as Reference Frequency þ Glitch-Free Switching þ 50% Duty Cycle þ Power Down Mode for Low Power consumption þ TTL or CMOS Compatible Outputs with 6 mA Drive Capability þ Low, Short- and Long-Term Jitter þ 16 Pin PDIP and 16 Pin SOIC (300 mil Body) Package Options BLOCK DIAGRAM 3 44.2 MHz 2 REF /4 or /12 14 The IMISG508 is a spectrum spread clock generator specially designed for personal computers, laser printers and other digital systems. IMISG508 uses a patented concept to generate popular clock frequencies that are intentionally boradbanded to reduce electromagnetic interference. IMISG508 attenuates the radiated emission amplitudes from products associated with either the clock harmonics or any signals derived from the clock signals nominally 10 dB and could significantly reduce the cost of complying with the regulatory requirements. PRCLK is the broadbanded output and can be programmed by the PRCLK Frequency Selection Table on page 2. A single, low cost external crystal is required as reference frequency for the synthesizer. Output modulation function can be turned off with the SSON pin. Several power down modes add the flexibility to operate the device in a completely static mode to reduce standby currents and simplify system board tests. CONNECTION DIAGRAM VDD OSCin OSCout VSS MPSEL AVDD S0 S1 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 TS VDD MPCLK VSS PRCLK AVSS LF1 SSON MPCLK APPLICATIONS MPSEL 5 LF 10 S0 7 SPECTRUM SPREAD S1 8 CLOCK GEN 16 TS SSON 12 /2 PRCLK The IMISG508 eliminates the need for multiple oscillators and generates the CPU clock signals for personal computers, laser printers and other digital systems. Supports CPUs from all major manufacturers. IMISG508 can be used with laptop or notebook computers to save power by running the system slower than normal CPU speeds or completely disabling the clocks in standby mode. 9 INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Rev. 1.0 Page 1 of 7 IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 PIN DESCRIPTION OSCin, OSCout - These pins form an on-chip reference oscillator when connected to terminals of an external 44.2 MHz third overtone parallel resonant crystal. OSCin may also serve as an input for an externally generated CMOS level or AC coupled reference signal. S0, and S1 - Frequency select inputs. These inputs control the PRCLK frequency selection. S0-S1 inputs control the CPU clock frequencies. All these inputs have internal pull-downs. PRCLK - Output from the spectrum spread clock generator. Frequency selection is shown in Table 1. Table 1 shows the output frequency selection conditions. TS - Controls power down and Tri-State Mode selection. When high, S1 input controls the mode selection as shown in Table 1 and Table 2. When low, the device operates in normal mode. This pin has an internal pull-down. LF1 - This is the control output for the clock generator, It is a single-ended, tri-state output. Component connections are shown in Figure 1. SSON - This pin controls the spectrum spread function. When low, PRCLK is modulated. When high, spreading is turned off. This pin has an internal pull-up. MPSEL - Controls MPCLK output frequency selections. Table 2 shows the selected frequencies for MPCLK. This input has an internal pull-up. MPCLK - This is a nonmodulated output. This output can be programmed to be 3.7 MHz or 11.06 MHz. The selection of these frequencies are controlled by the MPSEL pin shown in Table 1. VSS - Circuit ground. VDD - Positive power supply. AVSS - Analog circuit ground. AVDD - Analog positive power supply. LF 2k 2200 pf R2 330 pf C1 C2 PRCLK FREQUENCY TABLE INPUTS OUTPUT TS S1 S0 PRCLK 0 0 0 16.7 MHz 0 0 1 40 MHz 0 1 0 25 0 1 1 30 MHz 1 0 0 0; Power Down 1 0 1 1; Power Down 1 1 0 TEST 1 1 1 Hi-Z TABLE 1: When Power Down address is selected, the VCO is turned off and the device goes to standby mode. Phase detector is in tri-state mode. The Table is based on using 44.2 MHz crystal. Output can be scaled own using lower frequency crystals, see page 6. Page 2 of 7 MPCLK FREQUENCY SELECTION INPUTS OUTPUT TS MPSEL S1 S0 MPCLK 0 0 X X 3.7 MHz 0 1 X X 11.06 MHz 1 X 0 0 0; Power Down 1 X 0 1 1; Power Down 1 X 1 0 TEST 1 X 1 1 Hi-Z TABLE 2: When Power down address is selected, the VCO is turned off and the device goes to standby mode. Phase detector is in tri-state mode. INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Rev. 1.0 IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 MAXIMUM RATINGS This device contains circuitry to protect the inputs against damage due to high static voltages or electric field; however, precautions should be taken to avoid application of any voltage higher than the maximum rated voltages to this circuit. For proper operation, Vin and Vout should be constrained to the range: Voltage Relative to VSS: -03V to 6V Voltage Relative to VDD: 0.3V Storage Temperature: -65°C to 150°C Ambient Temperature: 0°C to 70°C Recommended Operating Range: 4.5 - 5.5V VSS < (Vin or Vout) < VDD Unused inputs must always be tied to an appropriate logic voltage level (either VSS or VDD). ELECTRICAL CHARACTERISTICS Characteristic Symbol Min Typ Max Units Input Low Voltage VIL - - 0.8 Vdc Input High Voltage VIH 2.0 - - Vdc IIH/IIL - - 10/100 uA VOL - - 0.4 Vdc VOH 2.5 - - Vdc Tri-State leakage Current IOZ - - 10 uA Static Supply Current IDD - - 250 uA Dynamic Supply Current ICC - 25 30 mA Short Circuit Current ISC 25 - - mA Input Low Current with Pull-up/Pull-down Output Low Voltage IOL = 6mA Output High Voltage IOH = 6mA VDD = 5V + 10%, TA = 0°°C to 70°°C INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Rev. 1.0 Page 3 of 7 IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 SWITCHING CHARACTERISTICS Characteristic Symbol Min Typ Max Units Output Rise and Fall Time Measured at 10% - 90% of VDD tTLH,tTHL - - 5 ns Output Rise and Fall Time Measured at 0.8V - 2.0V tTLH,tTHL - - 3 ns Output Duty Cycles TsymF1 - - 45/55 % tj1s - - 2 % of Fout Jitter One Sigma VDD = 5V + 10%, TA = 0°°C, CL = 15 pF OSCILLATOR CHARACTERISTICS Characteristic Symbol Min Typ Max Units Conditions Transconductance gm 20 80 180 millimhos @44.2 MHz Output Impedance Zo - 200 800 ohms @ 44.2 MHz Input Capacitance Ci 8 13 18 pf - Output Capacitance Co 3 6 9 pf - DC Bias Voltage VB 1.5 VDD/2 3.5 Volt - Start-up Time ts - - 2 ms @ VDD = 4.5V TsymF1 - - 45/55 % - Input Rise Time OSCin ICLKr - - 20 ns - Input Fall Time OSCout ICLKf - - 20 ns - Duty Cycle VCO CHARACTERISTICS Characteristic Symbol Min Typ Max Units Conditions VCO Gain K0 35 55 65 MHz/volt ∆F/∆V Measured with VCO Control at 2V - 3V Phase Detector Gain Kd 100 145 200 uA - Page 4 of 7 INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Rev. 1.0 IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 EXTERNAL CONNECTIONS VCC DIGITAL GND PLANE L1 DVDD DIGITAL POWER PLANE C11 10uF 1.5 uH ANALOG GND PLANE R1 AVDD ANALOG POWER PLANE C10 10 Ohms 22uF DVDD C3 10pF XTAL 44.2 MHz C5 C4 10pF SG508 C6 .1uF .033uF L2 1.2uH C7 10pF 1 2 3 4 5 6 7 8 VDD XIN XOUT VSS MPSEL AVDD S1 S0 TEST VDD MPCLK VSS PRCLK AVSS LF1 SSON 16 15 14 13 12 11 10 9 DVDD C9 .1uF JP5 1 2 HEADER R2 2K C8 .1uF AVDD MPSEL JP1 S0 JP2 C2 2200pF C1 330 pf S1 JP3 TEST JP4 DVDD NOTE1: KEEP C3, C4, C5, C6 CLOSE TO THEIR PINS (4, 11, 13, 10, 9 RESPECTIVELY). IMISG508 PACKAGE DRAWING AND DIMENSIONS INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Page 5 of 7 Rev. 1.0 IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 16 PIN SOIC OUTLINE DIMENSIONS C INCHES L H E D MILLIMETERS SYMBOL MIN NOM MAX MIN NOM MAX A 0.097 0.101 0.104 2.46 2.56 2.64 A1 0.0020 0.009 0.0015 0.060 0.22 0.38 A2 0.090 0.092 0.111 2.29 2.34 2.39 B 0.014 0.016 0.019 0.35 0.41 0.48 C 0.0091 0.010 0.0125 0.23 0.25 0.32 D .399 .407 .412 10.13 10.34 10.46 E 0.285 0.296 0.299 7.24 7.52 7.59 a A2 A A1 e B 0.050 BSC e SOIC PACKAGE (300 mil) 1.27 BSC H 0.400 0.406 0.410 10.16 10.31 10.41 a 0° 5° 10° 0° 5° 10° L 0.024 0.032 0.040 0.61 0.81 1.02 16-PIN PLASTIC DIP DIMENSIONS INCHES C E2 a E E1 D B2 Q2 Q A1 B1 S Page 6 of 7 e1 B A L MILLIMETERS SYMBOL MIN NOM MAX MIN NOM MAX A 0.150 0.160 0.170 3.81 4.06 4.318 A1 0.015 - - 0.381 - - B 0.016 0.018 0.020 0.40 0.45 0.50 B1 0.056 0.059 0.062 1.47 1.52 1.57 B2 0.046 0.049 0.052 1.17 1.24 1.32 C 0.008 0.010 0.012 0.20 0.25 0.30 D 0.748 0.750 0.752 19.00 19.05 19.10 E 0.300 0.312 0.325 7.62 7.924 8.255 E1 0.240 0.252 0.260 6.096 6.49 6.604 E2 0.335 0.345 0.355 8.51 8.76 9.01 0.100 BSC e1 2.54 BSC L 0.25 0.230 0.135 3.175 3.30 3.429 a 0° 7° 15° 0° 7° 15° Q1 0.059 0.060 0.061 1.50 1.53 1.55 Q2 0.128 0.130 0.132 3.25 3.30 3.35 S 0.073 0.075 0.077 1.85 1.90 1.95 INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Rev. 1.0 IMISG508 REDUCED EMI CLOCK CHIP CMOS LSI SPECTRUM SPREAD CLOCK GENERATOR May 1996 ORDERING INFORMATION Part Number Package Type IMISG508APB 16 Pin Plastic Dip Commercial, 0°C to + 70°C IMISG508AXB 16 Pin SOIC Commercial, 0°C to +70°C Note: Production Flow The ordering part number is formed by a combination of device number, device revision, package style, and screening as shown below. Marking: Example: IMI SG508APB Date Code, Lot # IMISG508APB Flow B = Commercial, 0°C to + 70°C Package P = Plastic Dip X = Small Outline Revision IMI Device Number INTERNATIONAL MICROCIRCUITS, INC. 525 LOS COCHES ST. MILPITAS, CA 95035 TEL: 408-263-6300 FAX 408-263-6571 Page 7 of 7 Rev. 1.0