Micrel, Inc. 3.3V 200MHz PRECISION SPREADSPECTRUM CLOCK SYNTHESIZER Precision Edge SY89529L DESCRIPTION FEATURES ■ Low voltage, 3.3V power supply operation ■ 200MHz precision LVPECL output from a low cost 16.66MHz crystal ■ 0.5% spread-spectrum modulation control ■ > 7dB reduction in EMI with spread-spectrum modulation ■ LVTTL/LVCMOS compatible control inputs ■ interfaces directly to a crystal ■ Precision PLL architecture ensures < 30ps peak-to-peak, cycle-to-cycle output jitter ■ 48%-to-52% precision duty cycle is ideal for doubledata-rate clocking applications ■ Available in low cost 32-pin TQFP and 28-pin SOIC packages The SY89529L is a high-speed, precision PLL-based LVPECL clock synthesizer with spread-spectrum modulation control. With an external 16.66MHz crystal providing a reference frequency to the internal PLL, the differential PECL output frequency will be 200MHz with < 30ps (20ps typ.) peak-to-peak, cycle-to-cycle output jitter. The SY89529L spread-spectrum mode operates with a 30kHz triangle modulation with 0.5% down-spread (+0.0%/ –0.5%). When spread-spectrum is activated, the output signal is modulated which spreads the peak amplitudes and, thus, decreases EMI (Electro-Magnetic Interference). APPLICATIONS ■ ■ ■ ■ M9999-110405 [email protected] or (408) 955-1690 Precision Edge® SY89529L ® High-speed synchronous systems CPU clock Multi-processor workstations and servers Networking Rev.: E 1 Amendment: /0 Issue Date: October 2005 Precision Edge® SY89529L Micrel, Inc. PACKAGE/ORDERING INFORMATION Ordering Information(1) NC 1 28 NC NC 2 27 VCC1 NC 3 26 XTAL2 NC 4 25 XTAL1 Package Operating Type Range Part Number Package Marking Lead Finish SY89529LZC Z28-1 Commercial SY89529LZC Sn-Pb SY89529LZCTR(2) Z28-1 Commercial SY89529LZC Sn-Pb SY89529LTC Sn-Pb SY89529LTC Sn-Pb NC 5 24 LOOP_REF SY89529LTC T32-1 Commercial NC 6 23 LOOP_FILTER SY89529LTCTR(2) T32-1 Commercial NC 7 22 VCC_ANALOG SY89529LZH(3) Z28-1 Commercial NC 8 SY89529LZH with Pb-Free Pb-Free bar-line indicator NiPdAu NC 9 20 NC SY89529LZHTR(2, 3) Z28-1 Commercial SY89529LZH with Pb-Free Pb-Free bar-line indicator NiPdAu SSC CONTROL(0) 10 19 NC SY89529LTH(3) T32-1 Commercial SSC CONTROL(1) 11 18 VCC_OUT SY89529LTH with Pb-Free Pb-Free bar-line indicator NiPdAu SY89529LTHTR(2, 3) T32-1 Commercial SY89529LTH with Pb-Free Pb-Free bar-line indicator NiPdAu TOP VIEW SOIC Z28-1 21 GND_ANALOG GND_TTL 12 17 FOUT TEST INPUT 13 16 /FOUT VCC_TTL 14 15 GND OUTPUT 3 LOOP_FILTER LOOP_REF XTAL1 6 29 NC NC GND_ANALOG VCC_ANALOG 32 31 30 TEST INPUT GND_TTL 1 /FOUT GND OUTPUT VCC_TTL VCC_OUT NC NC FOUT 28-Pin SOIC (Z28-1) 28 27 26 25 24 2 23 22 4 21 TQFP TOP VIEW T32-1* 5 20 19 7 18 8 NC NC SSC CONTROL(1) SSC CONTROL(0) NC NC NC NC NC NC 15 16 NC NC NC 12 13 14 NC XTAL2 10 11 VCC1 17 9 Notes: 1. Contact factory for die availability. Dice are guaranteed at TA = 25°C, DC Electricals only. 2. Tape and Reel. 3. Pb-Free package is recommended for new designs. 32-Pin TQFP (T32-1) M9999-110405 [email protected] or (408) 955-1690 2 Precision Edge® SY89529L Micrel, Inc. BLOCK DIAGRAM INTERFACE LOGIC ÷4 PLL PHASE DETECTOR 16.66MHz XTAL VCO FOUT Spread Spectrum Control Diagnostic Control ÷M SSC CTL 30-33kHz Down Spread 0.5% 2 200MHz /FOUT ÷N TEST OSC 1 Control TEST INPUT Commands Operational Modes SSC_CTL (1:0) VCO SSC FOUT, /FOUT 00 — — — Reserved (Supplier Internal Test Mode) 01 Run Run 200MHz Default SSC; Modulation Factor = 0.5% 10 Stop Stop TEST_I/O 11 Run Stop 200MHz Diagnostic Mode; (1MHz ≤ TEST INPUT ≤ 200MHz) No Spread-Spectrum Table 1. SY89529L Control/Operational Modes M9999-110405 [email protected] or (408) 955-1690 3 Precision Edge® SY89529L Micrel, Inc. PIN DESCRIPTIONS Input/Output Pins Pin Number SOIC Pin Number TQFP Pin Name I/O Pin Function 25,26 8, 9 XTAL1, XTAL2 Analog Inputs These pins form an oscillator when connected to an external crystal. Either series or parallel-resonant crystals are acceptable. Connect directly to the device. 10, 11 23, 24 SSC Control (0:1) LVTTL Inputs LVTTL-compatible spread-spectrum control pins. Data on control pins maintain device control. For spread-spectrum operation, leave SSC_0 and SSC_1 pins floating (default is spread ON). To reconfigure the device, simply change the SSC and the device will respond dynamically. SSC_0 = 24kΩ pullup. SSC_1 = 24kΩ pulldown 16, 17 30, 31 FOUT, /FOUT Differential Differential, LVPECL clock outputs. These outputs must be terminated to VCC –2V. (see Figure 6) 23 6 LOOP_FILTER Analog I/O Used for the R//C PLL loop filter. (see Figure 2.) 24 7 LOOP_REF Analog I/O Provides the reference voltage for the PLL. (see Figure 2). 13 27 TEST INPUT LVTTL Inputs Pin is used for test and debug purposes. Is intended to be left floating in production environment. Programmed as input in PLL-bypass mode. Pin includes an internal 24kΩ pullup resistor. Power Supply Pins Pin Number SOIC Pin Number TQFP Pin Name I/O Pin Function 14, 27 10, 28 VCC1, VCC_TTL Logic Power 22 5 ANALOG_ VCC Power PLL 18 32 VCC_OUT Output Power This is the positive power supply reference for the LVPECL outputs (FOUT and /FOUT). See Figure 5 for typical bypass circuit. 12 26 GND_TTL Logic This is the ground pin for for the TTL control logic. Normally connected to the logic ground. 21 4 GND_ANALOG Analog GND This is the ground pin for the PLL Core. Normally connected to a quiet, noise-free ground plane for low jitter perfomance. 15 29 GND_OUTPUT Output GND Ground for differential outputs. Normally connected to the logic ground plane. Pin Number SOIC Pin Number TQFP Pin Name I/O 1, 2, 3, 4, 5 6, 7, 8, 9, 19 20, 28 1, 2, 3, 11, 12, 13 14, 15, 16, 17, 18 19, 20, 21, 22, 25 NC No Connect 3.3V LVTTL core logic power-supply pins. Connect each pin directly to the logic-supply plane and use proper bypassing at each pin as close to the pin as possible; Ferrite bead in parallel with 1µF//0.01µF capacitors. (see Figure 5 for typical bypass circuit.) 3.3V PLL core supply pin. Must be a noise free supply. Bypass as close to the pin as possible; ferrite bead in parallel with 1µF//0.01µF capacitors. (see Figure 5 for typical bypass circuit.) No Connect Pins M9999-110405 [email protected] or (408) 955-1690 Pin Function 4 Pins are high-impedance, low leakage and are not used by internal circuits of the device. These pins are intended to be left floating in production. Precision Edge® SY89529L Micrel, Inc. FUNCTIONAL DESCRIPTION AND TEST MODES Introduction The SY89529L supports three operational modes, as shown in Table 1, page 2. The three modes are spread-spectrum clocking (SSC), non-spread-spectrum clock, and a test mode dynamically controlled with the SSC_Control pins. Unlike other synthesizers, the SY89529L can change spreadspectrum operation on the fly. In SSC mode, the output clock is modulated (30KHz, triangle waveform) in order to achieve a reduction in EMI. In the PLL-bypass test mode, the PLL is disconnected as the source to the differential output, thus allowing an external source to be connected to the TEST INPUT pin. This is useful for in-circuit testing by enabling the differential output to be driven at a lower frequency. SY89529L XTAL2 (Pin 26, SOIC) XTAL 16.666MHz XTAL1 (Pin 25, SOIC) Optional Quartz Crystal Selection: (1) Raltron Series Resonant: AS-16.666-S-SMD-T-MI (2) Raltron Parallel Resonant: AS-16.666-18-SMD-T-MI Figure 1. Crystal Interface Crystal Input and Oscillator Interface The SY89529L features a fully integrated on-board oscillator to minimize system implementation costs. The oscillator is a series resonant, multivibrator type design, and thus, a seriesresonant crystal is preferred, but not required. A parallel-resonant crystal can be used with the SY89529L with only a minor error in the desired frequency. A parallelresonant mode crystal used in a series resonant circuit will exhibit a frequency of oscillation a few hundred ppm lower than specified, a few hundred ppm translates to KHz inaccuracies. In a general computer application this level of inaccuracy is immaterial. As the oscillator is somewhat sensitive to loading on its inputs, the user is advised to mount the crystal as close to the SY89529L as possible to avoid any board level parasitics. In addition, trace lengths should be matched. Figure 1 shows how to interface with a crystal. Table 2 illustrates the crystal specifications. If a start-up problem occurs, consider adding a 10pf capacitor across XTAL1 and XTAL2. Loop Filter Design The filter for any Phase Locked Loop (PLL) based device deserves special attention. SY89529L provides filter pins for an external filter. A simple three-component passive filter is required for achieving ultra low jitter. Figure 2 shows the recommended three-components. Due to the differential design, the filter is connected between LOOP_FILTER and LOOP_REF pins. With this configuration, extremely high supply noise rejection is achieved. It is important that the filter circuit and filter pins be isolated from any non-common mode coupling plane. 560Ω 0.47µF 1000pF Loop Filter Loop Reference Figure 2. External Loop Filter Connection Output Frequency: 16.666MHz Mode of Oscillation: Fundamental Min. Typ. Max. Unit Frequency Tolerance @25°C — ±30 ±50 ppm Frequency Stability over 0°C to 70°C — ±50 ±100 ppm Operating Temperature Range –20 — +70 °C Storage Temperature Range –55 — +125 °C Aging (per yr/1st 3yrs) — — ±5 ppm Load Capacitance — 18 (or series) — pF Equivalent Series Resistance (ESR) — — 50 Ω Drive Level — 100 — µW Table 2. Quartz Crystal Oscillator Specifications M9999-110405 [email protected] or (408) 955-1690 5 Precision Edge® SY89529L Micrel, Inc. Spread Spectrum Spread-spectrum clocking is a frequency modulation technique for EMI reduction. When spread-spectrum is enabled, a 30kHz triangle waveform is used with 0.5% downspread (+0.0%/–0.5%) from the nominal 200MHz clock frequency. An example of a triangle frequency modulation profile is shown in the figure 3 below. The ramp profile can be expressed as: • Fnom = Nominal Clock Frequency in Spread OFF mode (200MHz with 16.66MHz IN) • Fm = Nominal Modulation Frequency (30kHz) • δ = Modulation Factor (0.5% down spread) The SY89529L triangle modulation frequency deviation (δ) will not exceed 0.6% down-spread from the nominal clock frequency (+0.0%/–0.5%). An example of the amount of down spread relative to the nominal clock frequency can be seen in the frequency domain, as shown in Figure 4. The ratio of this width to the fundamental frequency is typically 0.5%, and will not exceed 0.6%. The resulting spectral reduction will be greater than 7dB, as shown in Figure 5. It is important to note the SY89529L 7dB minimum spectral reduction is the component-specific EMI reduction, and will not necessarily be the same as the system EMI reduction. 200MHz Clock Output in Frequency Domain 1 , 2 fm 1 1 <t< (1 + δ ) fnom – 2 fm × δ × fnom × t when 2 fm fm (1 − δ ) fnom + 2 fm × δ × fnom × t (A) Spread-Spectrum OFF when 0 < t < (B) Spread-Spectrum ON R = 560Ω C1 = 1000pF C2 = 0.47µF VCC = 3.3V fnom TA = 25¡C (1–δ) fnom TIME (400µs/div.) t 0.5/fm 1/fm Figure 5. 200MHz Clock Output in Frequency Domain Figure 3. Triangle Frequency Modulation Figure 4. 0.38% Modulation, 32.7KHz Modulation Frequency M9999-110405 [email protected] or (408) 955-1690 6 Precision Edge® SY89529L Micrel, Inc. Power Supply Filtering Techniques As in any high speed integrated circuits, power supply filtering is very important. VCC1, VCC_Analog, VCC_TTL and VCC_OUT should be individually connected to the power supply plane through vias, and bypass capacitors should be used for each pin. To achieve optimum jitter performance, better power-supply isolation is required. In this case a ferrite bead along with a 1µF and a 0.01µF bypass capacitor should be connected to each power supply pin. Figure 6 illustrates power-supply filtering using ferrite beads and bypass capacitors. “Power Supply” side Ferrite Bead* Termination for PECL Outputs The differential PECL outputs, FOUT and /FOUT, are lowimpedance emitter-follower outputs. Therefore, terminating resistors (DC current path to ground) or current sources must be used for functionality. These outputs are designed to drive 50Ω transmission lines. Matched impedance techniques should be used to maximize operating frequency and minimize signal distortion. There are a few simple termination schemes. Figure 7 shows a common 3-resistor termination scheme. For more termination examples, see Micrel’s Application Note 9 online at www.micrel.com. Low impedance, emitter-follower outputs “Device” side SY89529L VCC Pins 22µF 1µF FOUT /FOUT 0.01µF z = 50Ω z = 50Ω 50Ω 50Ω 50Ω *For VCC_Analog,VCC_TTL, VCC1, use ferrite bead = 200mA, 0.45Ω DC, Murata P/N BLM21A1025 3-resistor network available* *3-resistor network = Thin-film Technologies, P/N TFT-RN1632-AN1DNC *For VCC_OUT use ferrite bead = 3A, 0.025Ω DC, Murata, P/N BLM31P005 Figure7. LVPECL Output Termination *Componet sizs: 0805 Figure 5. Power Supply Filtering M9999-110405 [email protected] or (408) 955-1690 7 Precision Edge® SY89529L Micrel, Inc. ABSOLUTE MAXIMUM RATINGS(1) Symbol Parameter Value Unit VCC Power Supply Voltage –0.5 to +7.0 V VIN Input Voltage –0.5 to +7.0 V IOUT Output Source 50 100 mA TLEAD Lead Temperature (soldering, 20sec.) 260 °C Tstore Storage Temperature –65 to +150 °C TA Operating Temperature –0 to +75 °C –Continuous –Surge NOTE: 1. Permanent device damage may occur if absolute maximum ratings are exceeded. This is a stress rating only and functional operation is not implied at conditions other than those detailed in the operational sections of this data sheet. Exposure to absolute maximum ratlng conditions for extended periods may affect device reliability. LVPECL DC ELECTRICAL CHARACTERISTICS VCC1 = VCC_Analog = VCC_TTL = VCC_OUT = +3.3V ±10%; TA = 0°C to +85°C Symbol Parameter Min. Typ. Max. Unit Condition VOH Output HIGH Voltage VCC_OUT –1.075 — VCC_OUT –0.830 V 50Ω to VCC_OUT –2V VOL Output LOW Voltage VCC_OUT –1.860 — VCC_OUT –1.570 V 50Ω to VCC_OUT –2V VCMR Common Mode Range 600 700 800 mV LVTTL DC ELECTRICAL CHARACTERISTICS VCC1 = VCC_Analog = VCC_TTL = VCC_OUT = +3.3V ±10%; TA = 0°C to +85°C Symbol Parameter Min. Typ. Max. Unit Power Supply Voltage (VCC_Analog, VCC1, VCC_OUT, VCC_TTL) 3.135 3.3 3.465 V Condition VIH Input HIGH Voltage SSC TEST INPUT 2.0 VCC/2 +0.3 — — VCC +0.3 — V V Note 1 VIL Input LOW Voltage SSC TEST INPUT –0.3 — — — 0.80 VCC/2 –0.3 V V Note 1 VIK Input Clamp Voltage — — –1.2 V IIN = –12mA IIH Input HIGH Current SSC TEST INPUT — — — — 50 50 µA µA Note 2 IIL Input LOW Current SSC TEST INPUT — — — — 0.60 0.60 mA mA Note 2 ICC Total Supply Current Typcial % of ICC — — — — — 110 14% 5% 5% 76% 145 — — — — mA No output load VCC1 VCC_OUT VCC_Analog VCC_TTL NOTES: 1. For TEST INPUT, input threshold is VCC/2. 2. Posituve and negative-going input threshold is set internally to track VCC/2. M9999-110405 [email protected] or (408) 955-1690 8 Precision Edge® SY89529L Micrel, Inc. AC ELECTRICAL CHARACTERISTICS VCC1 = VCC_Analog = VCC_TTL = VCC_OUT = +3.3V ±10%; TA = 0°C to +85°C Symbol Parameter Min. Typ. Max. Unit Condition FM SSC Modulation Frequency 30 — 33.33 KHz FMF SSC Modulation Factor — 0.5 0.6 % SRED'N Spectral Reduction 7 9 — dB FXTAL Crystal Input Range 14 16.66 18 MHz tDC Output Duty Cycle(1) 48 — 52 % FOUT = 200MHz tJIT Peak-to-Peak, Cycle-to-Cycle Jitter(1) — 20 30 ps FOUT = 200MHz tPERIOD Output Period(1) 4995 — 5005 ps FOUT = 200MHz tSTABLE Power-Up to Stable Clock Output — — 10 ms tr tf Output Rise/Fall Times (20% to 80%) 300 — 800 ps FOUT = 200MHz(2) FOUT, /FOUT NOTES: 1. Spread-spectrum clocking enabled. 2. SY89529L spectral reduction is the component-specific indication of EMI reduction. The SY89529L‘s spectral peak reduction is not necessarily the same as the system EMI reduction. M9999-110405 [email protected] or (408) 955-1690 9 Precision Edge® SY89529L Micrel, Inc. 28-PIN SOIC .300" WIDE (Z28-1) M9999-110405 [email protected] or (408) 955-1690 10 Precision Edge® SY89529L Micrel, Inc. 32-PIN TQFP (T32-1) Rev. 01 MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 TEL + 1 (408) 944-0800 FAX + 1 (408) 474-1000 WEB USA http://www.micrel.com The information furnished by Micrel in this datasheet is believed to be accurate and reliable. However, no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is at Purchaser’s own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2005 Micrel, Incorporated. M9999-110405 [email protected] or (408) 955-1690 11