(R) Product Proposal Alliance Semiconductor AS80M2183/84 EMI Reduction IC FEATURES * 2 spread % selections: AS80M2183: - 1.25% or - 3.75% AS80M2184: +/- 0.625% or +/- 1.875% * 3.3V operating voltage Generates a 1X low EMI spread spectrum clock from the input frequency * CMOS/TTL compatible inputs and outputs * Optimized for frequency range: * Low power CMOS design * Internal loop filter minimizes external components and board space * Supports notebook VGA and other LCD timing controller applications * AS80M2183: Down Spread AS80M2184: Center Spread * Products are available for industrial temperature range. * * Available in 8 pin SOIC and TSSOP Low inherent cycle-to-cycle jitter * FCC approved method of EMI attenuation * Provides up to 15 dB EMI reduction * AS80M2183/84: 6 MHz to 70 MHz PRODUCT DESCRIPTION The AS80M2183/84 is a versatile spread spectrum frequency modulator designed specifically for a wide range of input clock frequencies from 6 to 70 MHz (see Table 1). The AS80M2183/84 can generate an EMI reduced clock from an OSC or a system generated clock. The AS80M2183/84 reduces electromagnetic interference (EMI) at the clock source, allowing a system wide EMI reduction for all the down stream clocks and data dependent signals. The AS80M2183/84 allows significant system cost savings by reducing the number of circuit board layers, ferrite beads, shielding, and other passive components that are traditionally required to pass EMI regulations. Jul., 2003 Revision A The AS80M2183/84 modulates the output of a single PLL in order to "spread" the bandwidth of a synthesized clock, thereby decreasing the peak amplitudes of its harmonics. This results in significantly lower system EMI compared to the typical narrow band signal produced by oscillators and most clock generators. Lowering EMI by increasing a signal's bandwidth is called "spread spectrum clock generation". The AS80M2183/84 uses the most efficient and optimized modulation profile approved by the FCC and is implemented by using a proprietary alldigital method. APPLICATIONS The AS80M2183/84 is targeted towards EMI management for memory and LVDS interfaces in mobile graphic chipsets and high-speed digital applications such as PC peripheral devices, consumer electronics, and embedded controller systems. PulseCore - A Division of Alliance Semiconductor 3160 De La Cruz Blvd., Suite 200 * Santa Clara * CA * 95054 Tel (408) 748-6988 * Fax (408) 748-0009 http://www.alsc.com 1 of 5 (R) Product Proposal Alliance Semiconductor AS80M2183/84 Figure 1 - AS80M2183/84 Pin Diagrams XIN FS1 XOUT FS0 GND VDD SS% MODOUT AS80M2183/84 Figure 2 - AS80M2183/84 Block Diagram Jun., 2003 Revision A PulseCore - A Division of Alliance Semiconductor 3160 De La Cruz Blvd., Suite 200 * Santa Clara * CA * 95054 Tel (408) 748-6988 * Fax (408) 748-0009 http://www.alsc.com 2 of 5 (R) Product Proposal AS80M2183/84 Alliance Semiconductor Table 1- Input Frequency and Modulation Rate Part Number FS1 (pin 8) FS0 (pin 7) Frequency Range 0 0 6 MHz to 13 MHz 0 1 12 MHz to 25 MHz 1 0 18 MHz to 35 MHz 1 1 40 MHz to 70 MHz AS80M2183/84 Table 2 - Spread Deviation Selections Part Number AS80M2183 AS80M2184 SS% (pin 4) Spread Deviation 0 - 1.25% 1 - 3.75% 0 +/- 0.625% 1 +/- 1.875% PIN DESCRIPTION PIN # 1 2 3 4 Name XIN XOUT GND SS% Type I I P I 5 6 7 ModOut VDD FS0 O P I 8 FS1 I Jun., 2003 Revision A Description Connect to externally generated clock signal. Crystal Connection. Ground. Spread Range Select. Digital logic input used to select frequency deviation (see Table 2). This pin has an internal pull-up resistor. Spread Spectrum low EMI output Connect to +3.3V. Frequency range select. Digital Logic input used to select frequency range (see Table 1). This pin has an internal pull-up resistor. Frequency range select. Digital Logic input used to select frequency range (see Table 1). This pin has an internal pull-up resistor. PulseCore - A Division of Alliance Semiconductor 3160 De La Cruz Blvd., Suite 200 * Santa Clara * CA * 95054 Tel (408) 748-6988 * Fax (408) 748-0009 http://www.alsc.com 3 of 5 (R) Product Proposal AS80M2183/84 Alliance Semiconductor ABSOLUTE MAXIMUM RATINGS Symbol Parameter VDD, VIN TSTG TA Voltage on any pin with respect to GND Storage Temperature Operating Temperature Rating Unit -0.5 to +7.0 -65 to +125 0 to +70 V C C DC ELECTRICAL CHARACTERISTICS Symbol Parameter Min Typ Max Unit VIL VIH IIL IIH IXOL Input Low Voltage Input High Voltage Input Low Current Input High Current XOUT Output Low Current (@ 0.4V, VDD = 3.3V) XOUT Output High Current (@ 2.5V, VDD = 3.3V) Output Low Voltage (VDD=3.3V, IOL = 20 mA) Output High Voltage (VDD=3.3V, IOH = 20 mA) Static Supply Current Standby Mode Dynamic Supply Current Normal Mode (3.3V and 10 pF loading) Operating Voltage Power Up Time (First locked clock cycle after power up) Clock Output Impedance GND - 0.3 2.0 - TBD 0.8 VDD+0.3 -35 35 - V V A A mA - TBD - mA - - 0.4 V 2.5 - - V - 0.6 - mA 8.46 12 17.78 mA 2.7 - 3.3 0.18 3.7 - V mS - 50 - Min Typ Max Unit fIN Input Frequency 6 fOUT Output Frequency 6 tLH Output Rise Time 0.7 Note 1 (measured at 0.8V to 2.0V) tHL Output Fall Time 0.6 Note 1 (measured at 2.0V to 0.8V) tJC Jitter (cycle to cycle) tD Output Duty Cycle 45 Note1: tLH and tHL are measured into a capacitive load of 15pF 0.9 70 70 1.1 MHz MHz ns 0.8 1.0 ns 50 200 55 ps % IXOH VOL VOH IDD ICC VDD tON ZOUT AC ELECTRICAL CHARACTERISTICS Symbol Jun., 2003 Revision A Parameter PulseCore - A Division of Alliance Semiconductor 3160 De La Cruz Blvd., Suite 200 * Santa Clara * CA * 95054 Tel (408) 748-6988 * Fax (408) 748-0009 http://www.alsc.com 4 of 5 (R) Product Proposal Alliance Semiconductor AS80M2183/84 Figure 3 - Mechanical Package Outline (8 Pin SOIC) INCHES MILLIMETERS SYMBOL MIN NOR MAX MIN NOR MAX 0.057 0.064 0.071 1.45 1.63 1.80 A 0.004 0.007 0.010 0.10 0.18 0.25 A1 0.053 0.061 0.069 1.35 1.55 1.75 A2 0.012 0.016 0.020 0.31 0.41 0.51 B 0.004 0.006 0.001 0.10 0.15 0.25 C 0.186 0.194 0.202 4.72 4.92 5.12 D 0.148 0.156 0.164 3.75 3.95 4.15 E 0.050 BSC 1.27 BSC e 0.224 0.236 0.248 5.70 6.00 6.30 H 0.012 0.020 0.028 0.30 0.50 0.70 L 0 5 8 0 5 8 a Note: Controlling dimensions are millimeters. SOIC - 0.074 grams unit weight Figure 4 - Mechanical Package Outline (8 Pin TSSOP) INCHES MILLIMETERS SYMBOL MIN NOR MAX MIN NOR MAX 0.047 1.10 A 0.002 0.006 0.05 0.15 A1 0.031 0.039 0.041 0.80 1.00 1.05 A2 0.007 0.012 0.19 0.30 B 0.004 0.008 0.09 0.20 C 0.114 0.118 0.122 2.90 3.00 3.10 D 0.169 0.173 0.177 4.30 4.40 4.50 E 0.026 BSC 0.65 BSC e 0.244 0.252 0.260 6.20 6.40 6.60 H 0.018 0.024 0.030 0.45 0.60 0.75 L 0 8 0 8 a Note: Controlling dimensions are millimeters. TSSOP - 0.034 grams unit weight Jun., 2003 Revision A PulseCore - A Division of Alliance Semiconductor 3160 De La Cruz Blvd., Suite 200 * Santa Clara * CA * 95054 Tel (408) 748-6988 * Fax (408) 748-0009 http://www.alsc.com 5 of 5