SONET OC-12/OC-3 CLOCK SYNTHESIZER FEATURES ClockWorks™ SY89426 DESCRIPTION ■ Single chip source for 622.08MHz and 155.52MHz clocks ■ 622.08MHz output is differential PECL, 155.52MHz output is single-ended PECL ■ TTL/CMOS compatible inputs and reference output ■ SONET compliant jitter performance (≤0.01UI) ■ Choice of three reference frequencies ■ Only 395mW (typ) ■ Complies with Bellcore, CCITT and ANSI standards ■ Single +5 volt power supply ■ Fully compatible with industry standard 10KH I/O levels ■ Available in 28-pin PLCC package Micrel-Synergy's SY89426 Multi-Output Phase Locked Loop (PLL) is a SONET compliant clock generator providing 622.08MHz, 155.52MHz and retimed reference clock outputs. The PLL produces low jitter OC-12/STS-12 and OC-3/STS-3 rate clocks from an input reference clock of 38.88, 51.84, or 77.76MHz. Additionally, the input reference clock is retimed and provided as a TTL/CMOS compatible output, which may be disabled to minimize switching noise. The SY89426 operates from a single +5 volt supply, and requires only a simple series RC loop filter. Coupling Micrel-Synergy's advanced PLL technology with our proprietary ASSET™ bipolar process has produced a clock generator IC which exceeds applicable Bellcore and ANSI specifications, while setting a new standard for performance and flexibility. RETRFCK DISC VCC VCC FLTRN +5V RST +5V PIN CONFIGURATION FLTRP TYPICAL APPLICATION +3V SEL39 (TTL) RETRFCK (TTL) SEL78 (TTL) GND 155.52MHz CLOCK OUT RETIMED REFOUT RST DISC (TTL) (TTL) 17 SEL39 28 16 VCC CK622P SEL78 1 15 CK622N 14 VCCO PLCC TOP VIEW J28-1 RFCK 2 VCC 3 13 CK155 NC 4 12 GND 5 6 7 8 9 10 11 GND CK155 (PECL) 50Ω VCC 27 GND SY89426 1000Ω 18 GND NC +3V FLTRN 26 NC 0.1uF GND NC 622.08MHz CLOCK OUT CK622N FLTRP 25 24 23 22 21 20 19 2X 50Ω CK622P (PECL) GND VCCO RFCK (TTL) GND VCC CLOCK IN Rev.: F 1 Amendment: /0 Issue Date: July, 1999 ClockWorks™ SY89426 Micrel FUNCTIONAL BLOCK DIAGRAM VCCA GND 5 RFCK (TTL) Φ/f VCCO FLTRP/N 7 CHG PUMP FEEDBACK ÷ 2/3/4 RST (TTL) 622MHz VCO CK622P (PECL) DIVIDER ÷4 CK622N SEL39 (TTL) CK155 (PECL) SEL78 (TTL) RETRFCK (TTL) DISC (TTL) PIN DESCRIPTION INPUTS OUTPUTS RFCK [Reference Clock] TTL Reference clock IN. (38.88, 51.84 or 77.76MHz). CK622P, CK622N [622 Clock Output] Differential PECL. 622.08MHz output clock from PLL B. SEL39 [38.88MHz Select] TTL Logic HIGH on this pin denotes a 38.88MHz input reference clock. Tie to logic LOW if input is not 38.88MHz. CK155 [155 Clock Out] Single-ended PECL 155.52MHz output clock. RETRFCK [Retimed Reference Clock Out] TTL An output clock with the same frequency as the input Reference Clock (RFCK) and a 45-55% duty cycle. This output is derived by dividing the 622.08MHz output by the appropriate factor (e.g., divide by 16 for a 38.88MHz inout reference; divide by 12 for 51.84Mhz in; or divide by 8 for 77.76MHz in). SEL78 [77.76MHz Select] TTL Logic HIGH on this pin denotes a 77.76MHz input reference clock. Tie to logic LOW if input is not 77.76MHz. RST [Reset] TTL Tie to logic LOW for normal operation; logic HIGH forces reset of internal Phase Detector & feedback dividers. POWER & GROUND FLTRP, FLTRN [Loop Filter, Pos & Neg] Analog Connect a series RC loop filter between these pins. The suggested RC values are 500Ω and 0.1µF, as shown in the Typical Application. VCC VCCO GND DISC [Disable Clock] TTL Logic HIGH on this pin disables the Retimed Reference Clock output RETRFCK); if this output is not required, it is recommended that it be disabled to reduce switching noise. A logic LOW enables the output. 2 +5V for internal circuits. +5V for PECL outputs. Ground (0 volts). ClockWorks™ SY89426 Micrel REFERENCE FREQUENCY SELECTION(1) SEL39 SEL78 fRFCK 0 0 51.84 0 1 77.76 1 0 38.88 1 1 77.76 NOTE: 1. Airflow greater than 500lfpm is maintained. ABSOLUTE MAXIMUM RATINGS(1), (2) Symbol Parameter Rating Unit VCC Power Supply 0 to +7 V VI Input Voltage 0 to VCC V IOUT Output Current 50 100 mA TA Operating Temperature Range –40 to +85 °C Tstore Storage Temperature Range –65 to +150 °C –Continuous –Surge NOTES: 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 RATING conditions for extended periods may affect device reliability. 2. Airflow greater than 500lfpm is maintained. PECL DC ELECTRICAL CHARACTERISTIC(1), (2) VCC = VCCO = +5V ± 5%; GND = 0V; TA = –40°C to 85°C TA = –40°C Symbol TA = 0°C TA = +25°C TA = +85°C Parameter Min. Max. Min. Max. Min. Max. Min. Max. Unit VOH Output HIGH Voltage VCC -1130 VCC -840 VCC -1070 VCC -790 VCC -1030 VCC -760 VCC -960 VCC -670 mV VOL Output LOW Voltage VCC -2000 VCC -1600 VCC -2000 VCC -1580 VCC -2000 VCC -1580 VCC -2000 VCC -1545 mV VCC -1230 VCC -840 VCC -720 mV VCC -1480 VCC -1950 VCC -1480 VCC -1950 VCC -1445 mV VIH (1) Input HIGH Voltage (1) VIL Input LOW Voltage IIL Input LOW Current VCC -890 VCC -1170 VCC -1950 VCC -1500 VCC -1950 0.5 — 0.5 — VCC -1130 0.5 VCC -810 — VCC -1060 0.3 — NOTES: 1. Forcing one input at a time. Apply VIH (Max) or VIL (Min) to all other inputs. 2. Airflow greater than 500lfpm is maintained. TTL DC ELECTRICAL CHARACTERISTICS(1) VCC = VCCO = +5V ± 5%; GND = 0V; TA = –40°C to 85°C Symbol Parameter Min. Max. Unit Condition VOH Output HIGH Voltage 2.4 — V IOH = –2mA VOL Output LOW Voltage — 0.5 V IOL = 4mA IOS Output Short Circuit Current –150 –60 mA VOUT = 0 VIH Input HIGH Voltage 2.0 — V — VIL Input LOW Voltage — 0.8 V — NOTE: 1. Airflow greater than 500lfpm is maintained. 3 µA ClockWorks™ SY89426 Micrel (1) DC ELECTRICAL ELECTRICAL CHARACTERISTICS — TTL DC CHARACTERISTICS VCC = VCCO = +5V ± 5%; GND = 0V; TA = –40°C to 85°C Symbol Parameter Min. Typ. Max. Unit IEE Internal Operating Current — 79 120 mA IOUT Termination Output Current — 11 — mA Condition 50Ω to Vcc -2, 50% duty cycle NOTE: 1. Airflow greater than 500lfpm is maintained. AC ELECTRICAL CHARACTERISTICS(1) VCC = VCCO = +5V ± 5%; GND = 0V; TA = –40°C to 85°C Parameter Min. Typ. Max. 622.08 ±1% VCO Center Frequency Units Condition MHz Nominal Reference Clock (RFCK) Frequency Tolerance — — — ±20 ±20 ±10 — — — ppm ppm ppm 77.76MHz 51.84MHz 38.88MHz Reference Clock (RFCK) Input Duty Cycle 45 — 55 % of UI Reference Clock (RETRFCK) Output Duty Cycle 40 — 60 % of UI Acquisition Lock Time — — 15 µsec TTL Output Rise/Fall Time — — 2 ns 10% to 90% of amplitude, 15pF load PECL Output Rise/Fall Time — — 500 ps 10% to 90%, 50Ω load, 5pF cap CK622 Output Duty Cycle 45 — 55 % of UI CK155 Output Duty Cycle 45 — 55 % of UI tRST – RST pulse width 1 — — µsec tp622 Static Phase Offset of CK622 190 400 600 ps tp155 Static Phase Offset of CK155 –250 –400 –750 ps — +3.5 — ns tpREF Static Phase Offset of RETRFCK NOTE: 1. Airflow greater than 500lfpm is maintained. DC ELECTRICAL CHARACTERISTICS — TTL TIMING WAVEFORM RFCK Input tp 622 CK622 Output tp REF RETRFCK Output tp 155(1) CK155 Output NOTE: 1. Does not apply to 52MHz reference 4 15pF load ClockWorks™ SY89426 Micrel JITTER GENERATION Jitter Generation Definition Bellcore TR-NWT-000499 (Issue 4), section 7.3.3 "Jitter generation is the process whereby jitter appears at the output port of an individual unit of digital equipment in the absence of applied input jitter." Jitter Generation Requirement Bellcore TA-NWT-000253 (Issue 2), section 5.6.5.2 "For Category II interfaces, jitter generation shall not exceed 0.01 UI rms. For OC-N and STSX-N interfaces, a high-pass measurement filter with a 12kHz cutoff frequency shall be used." The low-pass cutoff frequency of the measurement filter shall be higher than 5MHz. The characteristic of the measurement filter is shown below. SONET OC-12 Category II Jitter Generation Measurement Filter Characteristics UI (rms) 0.01 +20dB/decade 12kHz Frequency Figure 1 PRODUCT ORDERING CODE Ordering Code Package Type Operating Range SY89426JC J28-1 Commercial SY89426JCTR J28-1 Commercial SY89426JI J28-1 Industrial SY89426JITR J28-1 Industrial 5 5MHz (minimum) ClockWorks™ SY89426 Micrel 28 LEAD PLCC (J28-1) Rev. 03 MICREL-SYNERGY TEL 3250 SCOTT BOULEVARD SANTA CLARA CA 95054 USA + 1 (408) 980-9191 FAX + 1 (408) 914-7878 WEB http://www.micrel.com This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc. © 2000 Micrel Incorporated 6