ZL30108 SONET/SDH Network Interface DPLL Data Sheet Features • • October 2004 Ordering Information Supports output wander and jitter generation specifications for GR-253-CORE OC-3 and G.813 STM-1 SONET/SDH interfaces ZL30108LDA -40°C to +85°C Accepts two input references and synchronizes to any combination of 2 kHz, 8 kHz, 1.544 MHz, 2.048 MHz, 8.192 MHz, 16.384 MHz or 19.44 MHz inputs • Provides a 19.44 MHz (SONET/SDH) clock output • Provides an 8 kHz framing pulse and a 2 kHz multi-frame pulse • Provides automatic entry into Holdover and return from Holdover • Hitless reference switching • Provides lock and accurate reference fail indication • Loop filter bandwidth of 29 Hz or 14 Hz • Less than 24 psrms intrinsic jitter on the 19.44 MHz output clock, compliant with GR-253-CORE OC-3 and G.813 STM-1 specifications • Less than 0.5 nspp intrinsic jitter on output frame pulses • External master clock source: clock oscillator or crystal • Simple hardware control interface OSCi OSCo 32 pin QFN Applications • Line card synchronization for SONET/SDH systems Description The ZL30108 SONET/SDH network interface digital phase-locked loop (DPLL) provides timing and synchronization for SONET/SDH network interface cards. The ZL30108 generates a SONET/SDH clock and framing signals that are phase locked to one of two backplane or network references. It helps ensure system reliability by monitoring its references for frequency accuracy and stability and by maintaining tight phase alignment between the input reference clock and clock outputs. The ZL30108 output clock’s wander and jitter generation are compliant with GR-253-CORE OC-3 and G.813 STM-1 specifications. LOCK TIE_CLR Master Clock REF0 REF1 REF_FAIL0 REF_FAIL1 OOR_SEL TIE Corrector Circuit MUX Reference Monitor RST DPLL Frequency Synthesizer TIE Corrector Enable Mode Control REF_SEL MODE_SEL Virtual Reference State Machine Frequency Select Figure 1 - Functional Block Diagram 1 Zarlink Semiconductor Inc. Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc. Copyright 2004, Zarlink Semiconductor Inc. All Rights Reserved. C19o F8ko F2ko ZL30108 Data Sheet Table of Contents 1.0 Pin Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.0 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1 Reference Select Multiplexer (MUX) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.2 Reference Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.3 Time Interval Error (TIE) Corrector Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.4 Digital Phase Lock Loop (DPLL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 2.5 Frequency Synthesizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.6 State Machine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 2.7 Master Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.0 Control and Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.1 Out of Range Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.2.1 Freerun Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.2.2 Normal Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 3.3 Reference Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.0 Measures of Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.1 Jitter Generation (Intrinsic Jitter) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.2 Jitter Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.3 Jitter Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 4.4 Frequency Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.5 Holdover Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.6 Capture Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.7 Lock Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.8 Time Interval Error (TIE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.9 Maximum Time Interval Error (MTIE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.10 Phase Continuity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 4.11 Phase Lock Time. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 5.0 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 5.1 Power Supply Decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 5.2 Master Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 5.2.1 Clock Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 5.2.2 Crystal Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 5.3 Power Up Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 5.4 Reset Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 6.0 Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.1 AC and DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 6.2 Performance Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 2 Zarlink Semiconductor Inc. ZL30108 Data Sheet List of Figures Figure 1 - Functional Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Figure 2 - Pin Connections (32 pin 5 mm X 5 mm QFN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Figure 3 - Reference Monitor Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Figure 4 - Behavior of the Dis/Requalify Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 5 - Out-of-Range Thresholds for OOR_SEL=1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Figure 6 - Out-of-Range Thresholds for OOR_SEL=0. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Figure 7 - Timing Diagram of Hitless Reference Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Figure 8 - DPLL Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Figure 9 - Mode Switching in Normal Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Figure 10 - Recommended Power Supply Decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Figure 11 - Clock Oscillator Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 12 - Crystal Oscillator Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 13 - Power-Up Reset Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 14 - Timing Parameter Measurement Voltage Levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Figure 15 - Input to Output Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 16 - SONET/SDH Output Timing Referenced to F8ko . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 3 Zarlink Semiconductor Inc. 24 20 AGND Data Sheet AVCORE AVDD F2ko C19o 22 AGND REF_SEL AGND AVDD F8ko ZL30108 18 16 ZL30108 26 AVDD REF0 REF1 14 12 33 IC (E-pad) 10 32 RST MODE_SEL GND 8 AVCORE REF_FAIL0 VCORE 6 REF_FAIL1 4 LOCK VCORE 2 GND OSCi OSCo 30 VDD TIE_CLR VDD IC 28 OOR_SEL IC GND Figure 2 - Pin Connections (32 pin 5 mm X 5 mm QFN) 4 Zarlink Semiconductor Inc. ZL30108 1.0 Data Sheet Pin Description Pin # Name Description 1 GND 2 VCORE Positive Supply Voltage. +1.8 VDC nominal 3 LOCK Lock Indicator (Output). This output goes to a logic high when the PLL is frequency locked to the selected input reference. 4 REF_FAIL0 Reference 0 Failure Indicator (Output). A logic high at this pin indicates that the REF0 reference frequency has exceeded the out-of-range limit set by the OOR_SEL pin or that it is exhibiting abrupt phase or frequency changes. 5 REF_FAIL1 Reference 1 Failure Indicator (Output). A logic high at this pin indicates that the REF1 reference frequency has exceeded the out-of-range limit set by the OOR_SEL pin or that it is exhibiting abrupt phase or frequency changes. 6 VCORE 7 AVCORE 8 GND 9 MODE_SEL 10 RST Reset (Input). A logic low at this input resets the device. On power up, the RST pin must be held low for a minimum of 300 ns after the power supply pins have reached the minimum supply voltage. When the RST pin goes high, the device will transition into a Reset state for 3 ms. In the Reset state all outputs will be forced into high impedance. 11 OSCo Oscillator Master Clock (Output). For crystal operation, a 20 MHz crystal is connected from this pin to OSCi. This output is not suitable for driving other devices. For clock oscillator operation, this pin must be left unconnected. 12 OSCi Oscillator Master Clock (Input). For crystal operation, a 20 MHz crystal is connected from this pin to OSCo. For clock oscillator operation, this pin must be connected to a clock source. 13 IC 14 VDD Positive Supply Voltage. +3.3 VDC nominal 15 AVDD Positive Analog Supply Voltage. +3.3 VDC nominal 16 GND Ground. 0 V 17 AGND 18 AVCORE Positive Analog Supply Voltage. +1.8 VDC nominal 19 AVDD Positive Analog Supply Voltage. +3.3 VDC nominal 20 F2ko Multi Frame Pulse (Output). This is a CMOS 2 kHz active high 51 ns framing pulse, which marks the beginning of a multi frame. Ground. 0 V Positive Supply Voltage. +1.8 VDC nominal. Positive Analog Supply Voltage. +1.8 VDC nominal. Ground. 0 V Mode Select (Input). This input determines the mode of operation: See Table 3. 0: Normal mode (device locked to input reference) 1: Freerun mode Internal Connection. Connect this pin to VDD. Analog Ground. 0 V This clock output pad includes a Schmitt triggered input which serves as a PLL feedback path; proper transmission-line termination should be applied to maintain reflections below Schmitt trigger levels. 5 Zarlink Semiconductor Inc. ZL30108 Pin # Name 21 C19o Data Sheet Description Clock 19.44 MHz (Output). This CMOS output is used in SONET/SDH applications. This clock output pad includes a Schmitt input which serves as a PLL feedback path; proper transmission-line termination should be applied to maintain reflections below Schmitt trigger levels. 22 AGND Analog Ground. 0 V 23 AVDD Positive Analog Supply Voltage. +3.3 VDC nominal 24 F8ko Frame Pulse (Output). This is an CMOS 8 kHz active high 31 ns framing pulse, which marks the beginning of a 125 us frame. This clock output pad includes a Schmitt input which serves as a PLL feedback path; proper transmission-line termination should be applied to maintain reflections below Schmitt trigger levels. 25 AGND Analog Ground. 0 V 26 REF_SEL 27 REF0 Reference (Input). This is one of two (REF0 and REF1) input reference sources used for synchronization. One of seven possible frequencies may be used: 2 kHz, 8 kHz, 1.544 MHz, 2.048 MHz, 8.192 MHz,16.384 MHz or 19.44 MHz. This pin is internally pulled down to GND. 28 REF1 Reference (Input). See REF0 pin description. 29 OOR_SEL 30 IC 31 VDD 32 TIE_CLR 33 IC Reference Select 0 (Input/Output). As an input REF_SEL selects the reference input that is used for synchronization; See Table 4. 0: REF0 1: REF1 This pin is internally pulled down to GND. Out Of Range Selection (Input). This input selects the frequency acceptance limits of the reference monitor: See Table 2. 0: 40 - 52 ppm 1: 64 - 83 ppm Internal Connection. Connect this pin to GND. Positive Supply Voltage. +3.3 VDC nominal. TIE Circuit Reset (Input). A logic low at this input resets the Time Interval Error (TIE) correction circuit resulting in a realignment of input phase with output phase. Internal Connection. Package E-pad, this pin is internally connected to device GND, it can be left unconnected or it can be connected to GND. 6 Zarlink Semiconductor Inc. ZL30108 2.0 Data Sheet Functional Description The ZL30108 is a SONET/SDH Network Interface DPLL, providing timing (clock) and synchronization (frame) signals to SONET/SDH network interface cards. Figure 1 is a functional block diagram which is described in the following sections. 2.1 Reference Select Multiplexer (MUX) The ZL30108 accepts two simultaneous reference input signals and operates on their rising edges. One of two, the primary reference (REF0) or the secondary reference (REF1) signal is selected as input to the TIE Corrector Circuit based on the Reference Selection (REF_SEL) input. 2.2 Reference Monitor The input references are monitored by two independent reference monitor blocks, one for each reference. The block diagram of a single reference monitor is shown in Figure 3. For each reference clock, the frequency is detected and the clock is continuously monitored for three independent criteria that indicate abnormal behavior of the reference signal, for example; long term drift from its nominal frequency or excessive jitter. To ensure proper operation of the reference monitor circuit, the minimum input pulse width restriction of 15 nsec must be observed. • Reference Frequency Detector (RFD): This detector determines whether the frequency of the reference clock is 2 kHz, 8 kHz, 1.544 MHz, 2.048 MHz 8.192 MHz, 16.384 MHz or 19.44 MHz and provides this information to the various monitor circuits and the phase detector circuit of the DPLL. • Precise Frequency Monitor (PFM): This circuit determines whether the frequency of the reference clock is within the applicable accuracy range defined by the OOR_SEL pin, see Figure 5, Figure 6 and Table 2. It will take the precise frequency monitor up to 10 s to qualify or disqualify the input reference. • Coarse Frequency Monitor (CFM): This circuit monitors the reference over intervals of approximately 30 µs to quickly detect large frequency changes. • Single Cycle Monitor (SCM): This detector checks the period of a single clock cycle to detect large phase hits or the complete loss of the clock. Reference Frequency Detector REF0 / REF1 REF_FAIL0 / REF_FAIL1 OR Precise Frequency Monitor Coarse Frequency Monitor Single Cycle Monitor dis/requalify timer REF_DIS Mode select state machine OR HOLDOVER REF_DIS= reference disrupted (internal signal) Figure 3 - Reference Monitor Circuit 7 Zarlink Semiconductor Inc. ZL30108 Data Sheet Exceeding the threshold of any of the monitors forces the corresponding REF_FAIL pin to go high. The single cycle and coarse frequency failure flags force the DPLL into Holdover mode and feed a timer that disqualifies the reference input signal when the failures are present for more than 2.5 s. The single cycle and coarse frequency failures must be absent for 10 s to let the timer requalify the input reference signal as valid. Multiple failures of less than 2.5 s each have an accumulative effect and will disqualify the reference. This is illustrated in Figure 4. SCM or CFM failure current REF timer 2.5 s 10 s REF_FAIL HOLDOVER Figure 4 - Behavior of the Dis/Requalify Timer When the incoming signal returns to normal (REF_FAIL=0), the DPLL returns to Normal mode with the output signal locked to the input signal. Each of the monitors has a built-in hysteresis to prevent flickering of the REF_FAIL status pin at the threshold boundaries. The precise frequency monitor and the timer do not affect the mode (Holdover/Normal) of the DPLL. C20i Clock Accuracy Out of Range C20 0 ppm In Range -83 -64 0 64 83 Out of Range C20 +32 ppm In Range -51 96 32 -32 115 Out of Range C20 -32 ppm -115 -96 -100 -32 -75 -50 -25 32 0 25 In Range 51 50 75 100 Figure 5 - Out-of-Range Thresholds for OOR_SEL=1 8 Zarlink Semiconductor Inc. Frequency offset [ppm] ZL30108 Data Sheet C20i Clock Accuracy Out of Range C20 0 ppm In Range -52 -40 0 40 52 Out of Range C20 +20 ppm In Range -32 -20 60 20 72 Out of Range C20 -20 ppm -72 -60 -100 -75 -50 20 -32 -25 0 In Range 32 25 50 75 100 Frequency offset [ppm] Figure 6 - Out-of-Range Thresholds for OOR_SEL=0 2.3 Time Interval Error (TIE) Corrector Circuit The TIE Corrector Circuit eliminates phase transients on the output clock that may occur in the course of recovery from Automatic Holdover mode to Normal mode. On recovery from Automatic Holdover mode or when switching to another reference input, the TIE corrector circuit measures the phase delay between the current phase (feedback signal) and the phase of the selected reference signal. This delay value is stored in the TIE corrector circuit. This circuit creates a new virtual reference signal that is at the same phase position as the feedback signal. By using the virtual reference, the PLL minimizes the phase transient it experiences when it switches to another reference input or recovers from Automatic Holdover mode. The delay value can be reset by setting the TIE Corrector Circuit Clear pin (TIE_CLR) low for at least 15 ns. This results in a phase alignment between the input reference signal and the output clocks and frame pulses as shown in Figure 15 and Figure 16. The speed of the phase alignment correction is limited by the loop filter bandwidth. Convergence is always in the direction of least phase travel. TIE_CLR can be kept low continuously. In that case the output clocks will always align with the selected input reference. This is illustrated in Figure 7. 9 Zarlink Semiconductor Inc. ZL30108 Data Sheet TIE_CLR = 0 TIE_CLR = 1 locked to REF0 locked to REF0 REF0 REF0 REF1 REF1 Output Clock Output Clock locked to REF1 locked to REF1 REF0 REF0 REF1 REF1 Output Clock Output Clock Figure 7 - Timing Diagram of Hitless Reference Switching 10 Zarlink Semiconductor Inc. ZL30108 2.4 Data Sheet Digital Phase Lock Loop (DPLL) The DPLL of the ZL30108 consists of a phase detector, a integrated on-chip loop filter and an digitally controlled oscillator as shown in Figure 8. The data path from the phase detector to the filter is tapped and routed to the lock indicator that provides a lock indication which is output at the LOCK pin. lock indicator virtual reference from TIE corrector circuit phase detector loop filter digitally controlled oscillator LOCK DPLL reference to frequency synthesizer state select from control state machine feedback signal from frequency select MUX Figure 8 - DPLL Block Diagram Phase Detector - the phase detector compares the virtual reference signal from the TIE corrector circuit with the feedback signal and provides an error signal corresponding to the phase difference between the two. This error signal is passed to the loop filter circuit. Loop Filter - the loop filter is similar to a first order low pass filter with bandwidth of 29 Hz, suitable to provide timing and synchronization for SONET/SDH network interface cards. Detected REF Frequency Loop Filter Bandwidth 2 kHz 14 Hz 8 kHz, 1.544 MHz, 2.048 MHz, 8.192 MHz, 16.384 MHz, 19.44 MHz 29 Hz Table 1 - Loop Filter Bandwidth Settings 11 Zarlink Semiconductor Inc. ZL30108 Data Sheet Digitally Controlled Oscillator (DCO) - the DCO receives the limited and filtered signal from the Loop Filter, and based on its value, generates a corresponding digital output signal. The synchronization method of the DCO is dependent on the state of the ZL30108. In Normal Mode, the DCO provides an output signal which is frequency and phase locked to the selected input reference signal. In the Automatic Holdover mode, the DCO is free running at a frequency equal to the frequency that the DCO was generating in Normal Mode. The frequency in the Automatic Holdover mode is calculated from frequency samples stored 26 ms to 52 ms before the ZL30108 entered the Automatic Holdover mode. This ensures that the coarse frequency monitor and the single cycle monitor have time to disqualify a bad reference before it corrupts the holdover frequency. In Freerun Mode, the DCO is free running with an accuracy equal to the accuracy of the OSCi 20 MHz source. Lock Indicator - the lock detector monitors if the output value of the phase detector is within the phase-lockwindow for a certain time. The selected phase-lock-window guarantees the stable operation of the LOCK pin with maximum network jitter and wander on the reference input. If the DPLL goes into the Automatic Holdover mode, the LOCK pin will initially stay high for 0.1 s. If at that point the DPLL is still in the Automatic Holdover mode, the LOCK pin will go low. In Freerun mode the LOCK pin will go low immediately. 2.5 Frequency Synthesizers The output of the DCO is used by the frequency synthesizers to generate the output clocks and frame pulses which are synchronized to one of the input references (REF0 or REF1). The frequency synthesizer uses digital techniques to generate output clocks and advanced noise shaping techniques to minimize the output jitter. The clock and frame pulse outputs have limited drive capability and should be buffered when driving high capacitance loads. 2.6 State Machine As shown in Figure 1, the state machine controls the TIE Corrector Circuit and the DPLL. The control of the ZL30108 is based on the input MODE_SEL. 2.7 Master Clock The ZL30108 can use either a clock or crystal as the master timing source. For recommended master timing circuits, see the Applications - Master Clock section. 12 Zarlink Semiconductor Inc. ZL30108 3.0 Control and Modes of Operation 3.1 Out of Range Selection Data Sheet The frequency out of range limits for the precise frequency monitoring in the reference monitors are selected by the OOR_SEL pin, see Table 2. OOR_SEL Out Of Range Limits 0 40 - 52 ppm 1 64 - 83 ppm Table 2 - Out of Range Limits Selection 3.2 Modes of Operation The ZL30108 has two possible manual modes of operation; Normal and Freerun. These modes are selected with mode select pins MODE_SEL as is shown in Table 3. Transitioning from one mode to the other is controlled externally. MODE_SEL Mode 0 Normal (with automatic Holdover) 1 Freerun Table 3 - Operating Modes 3.2.1 Freerun Mode Freerun mode is typically used when an independent clock source is required, or immediately following system power-up before network synchronization is achieved. In Freerun mode, the ZL30108 provides timing and synchronization signals which are based on the master clock frequency (supplied to OSCi pin) only, and are not synchronized to the reference input signals. The accuracy of the output clock is equal to the accuracy of the master clock (OSCi). So if a ±32 ppm output clock is required, the master clock must also be ±32 ppm. See Applications - Section 5.2, “Master Clock“. 3.2.2 Normal Mode Normal mode is typically used when a system clock source, synchronized to the network or a backplane is required. In Normal mode, the ZL30108 provides timing and frame synchronization signals, which are synchronized to one of two reference inputs (REF0 or REF1). The input reference signal may have a nominal frequency of 2 kHz, 8 kHz, 1.544 MHz, 2.048 MHz, 8.192 MHz, 16.384 MHz or 19.44 MHz. The frequency of the reference inputs are automatically detected by the reference monitors. When the Normal mode is selected through the MODE_SEL pin, the ZL30108 will automatically go into the Automatic Holdover mode if the currently selected reference is disrupted (see Figure 9). After the power up reset, the ZL30108 will initially go into the Automatic Holdover mode, generating clocks with the same accuracy as it would be in the Freerun mode. If the currently selected reference is not disrupted (see Figure 3), the state machine takes the DPLL out of the Automatic Holdover mode. The transition is done through the TIE correction state and the current phase offset of the output signals to the input reference is maintained. 13 Zarlink Semiconductor Inc. ZL30108 Data Sheet If the current reference experiences an disruption while the device is in Normal mode, the device will go automatically into Automatic Holdover mode. It will return to Normal mode as soon as the reference is valid again. If the reference selection changes because the value of the REF_SEL pin change the ZL30108 goes into Automatic Holdover mode and returns to Normal mode through the TIE correction state. Normal (locked) REF_DIS=0 and REF_CH=0 REF_DIS=0 RST REF_CH=1 REF_DIS=1 REF_DIS=1 TIE Correction Holdover (REF_DIS=0) or REF_CH=1 REF_DIS=1: Current selected reference disrupted (see Figure 3) REF_CH= 1: Reference change, a transition in the reference selection (a change in the REF_SEL pin). Figure 9 - Mode Switching in Normal Mode Automatic Holdover Mode Automatic Holdover mode is typically used for short durations while system synchronization is temporarily disrupted. In Automatic Holdover mode, the ZL30108 provides timing and synchronization signals, which are not locked to an external reference signal, but are based on storage techniques. The storage value is determined while the device is in Normal Mode and locked to an external reference signal. When in Normal Mode, and locked to the input reference signal, a numerical value corresponding to the ZL30108 output reference frequency is stored alternately in two memory locations every 26 ms. When the device is switched into Automatic Holdover mode, the value in memory from between 26 ms and 52 ms is used to set the output frequency of the device. The frequency accuracy of Automatic Holdover mode is 0.01 ppm. Two factors affect the accuracy of Automatic Holdover mode. One is drift on the master clock while in Automatic Holdover mode, drift on the master clock directly affects the Automatic Holdover mode accuracy. Note that the absolute master clock (OSCi) accuracy does not affect Holdover accuracy, only the change in OSCi accuracy while in Holdover. For example, a ±32 ppm master clock may have a temperature coefficient of ±0.1 ppm per °C. So a ±10 °C change in temperature, while the ZL30108 is in the Automatic Holdover mode may result in an additional offset (over the 0.01 ppm) in frequency accuracy of ±1 ppm, which is much greater than the 0.01 ppm of the ZL30108. The other factor affecting the accuracy is large jitter on the reference input prior (26 ms to 52 ms) to the mode switch. 14 Zarlink Semiconductor Inc. ZL30108 3.3 Data Sheet Reference Selection The active reference input (REF0 or REF1) is selected by the REF_SEL pin as shown in Table 4. If the logic value of the REF_SEL pin is changed when the DPLL is in Normal mode, the ZL30108 will perform a hitless reference switch. REF_SEL (input pin) Input Reference Selected 0 REF0 1 REF1 Table 4 - Manual Reference Selection When the REF_SEL inputs are used to force a change from the currently selected reference to another reference, the action of the LOCK output will depend on the relative frequency and phase offset of the old and new references. Where the new reference has enough frequency offset and/or TIE-corrected phase offset to force the output outside the phase-lock-window, the LOCK output will de-assert, the lock-qualify timer is reset, and LOCK will stay de-asserted for the full lock-time duration. Where the new reference is close enough in frequency and TIEcorrected phase for the output to stay within the phase-lock-window, the LOCK output will remain asserted through the reference-switch process. 4.0 Measures of Performance The following are some PLL performance indicators and their corresponding definitions. 4.1 Jitter Generation (Intrinsic Jitter) Timing jitter is defined as the high frequency variation of the clock edges from their ideal positions in time. Wander is defined as the low-frequency variation of the clock edges from their ideal positions in time. High and low frequency variation imply phase oscillation frequencies relative to some demarcation frequency. (Often 10 Hz or 20 Hz for DS1 or E1, higher for SONET/SDH clocks.) Jitter parameters given in this data sheet are total timing jitter numbers, not cycle-to-cycle jitter. 4.2 Jitter Tolerance Jitter tolerance is a measure of the ability of a PLL to operate properly (i.e., remain in lock and or regain lock in the presence of large jitter magnitudes at various jitter frequencies) when jitter is applied to its reference. The applied jitter magnitude and jitter frequency depends on the applicable standards. 4.3 Jitter Transfer Jitter transfer or jitter attenuation refers to the magnitude of jitter at the output of a device for a given amount of jitter at the input of the device. Input jitter is applied at various amplitudes and frequencies, and output jitter is measured with various filters depending on the applicable standards. For the ZL30108, the internal low pass loop filter determines the jitter attenuation. Since intrinsic jitter is always present, jitter attenuation will appear to be lower for small input jitter signals than for large ones. Consequently, accurate jitter transfer function measurements are usually made with large input jitter signals (for example 75% of the specified maximum tolerable input jitter). 4.4 Frequency Accuracy Frequency accuracy is defined as the absolute accuracy of an output clock signal when it is not locked to an external reference, but is operating in a free running mode. For the ZL30108, the Freerun accuracy is equal to the master clock (OSCi) accuracy. 15 Zarlink Semiconductor Inc. ZL30108 4.5 Data Sheet Holdover Accuracy Holdover accuracy is defined as the absolute frequency accuracy of an output clock signal, when it is not locked to an external reference signal, but is operating using storage techniques. For the ZL30108, the storage value is determined while the device is in Normal Mode and locked to an external reference signal. 4.6 Capture Range Also referred to as pull-in range. This is the input frequency range over which the PLL must be able to pull into synchronization. The ZL30108 capture range is equal to ±130 ppm minus the accuracy of the master clock (OSCi). For example, a +32 ppm master clock results in a capture range of +162 ppm on one side and -98 ppm on the other side of frequency range. 4.7 Lock Range This is the input frequency range over which the synchronizer must be able to maintain synchronization. The lock range is equal to the capture range for the ZL30108. 4.8 Time Interval Error (TIE) TIE is the time delay between a given timing signal and an ideal timing signal. 4.9 Maximum Time Interval Error (MTIE) MTIE is the maximum peak to peak delay between a given timing signal and an ideal timing signal within a particular observation period. 4.10 Phase Continuity Phase continuity is the phase difference between a given timing signal and an ideal timing signal at the end of a particular observation period. Usually, the given timing signal and the ideal timing signal are of the same frequency. Phase continuity applies to the output of the PLL after a signal disturbance due to a reference switch or a mode change. The observation period is usually the time from the disturbance, to just after the synchronizer has settled to a steady state. 4.11 Phase Lock Time This is the time it takes the PLL to phase lock to the input signal. Phase lock occurs when the input signal and output signal are aligned in phase with respect to each other within a certain phase distance (not including jitter). Lock time is affected by many factors which include: • initial input to output phase difference • initial input to output frequency difference • PLL loop filter bandwidth • in-lock phase distance The presence of input jitter makes it difficult to define when the PLL is locked as it may not be able to align its output to the input within the required phase distance, dependent on the PLL bandwidth and the input jitter amplitude and frequency. Although a short lock time is desirable, it is not always possible to achieve due to other synchronizer requirements. For instance, better jitter transfer performance is achieved with a lower frequency loop filter which increases lock time. See Section 6.2, “Performance Characteristics“ for Maximum Phase Lock Time. 16 Zarlink Semiconductor Inc. ZL30108 5.0 Data Sheet Applications This section contains ZL30108 application specific details for power supply decoupling, clock and crystal operation, reset operation,and control operation. 5.1 Power Supply Decoupling It is recommended to place a 100 nF decoupling capacitor close to the power and ground pairs as shown in Figure 11 to ensure optimal jitter performance. 3.3 V 1.8 V AV CORE 18 23 AV DD 100 nF 100 nF 25 AGND AV CORE 7 19 AV DD 100 nF 100 nF V CORE 6 22 AGND 100 nF GND 8 15 AV DD 100 nF V CORE 2 17 AGND 100 nF GND 1 14 V DD 100 nF 16 GND 31 V DD ZL30108 100 nF 1 GND Figure 10 - Recommended Power Supply Decoupling 17 Zarlink Semiconductor Inc. ZL30108 5.2 Data Sheet Master Clock The ZL30108 can use either a clock or crystal as the master timing source. Zarlink Application Note ZLAN-68 lists a number of applicable oscillators and crystals that can be used with the ZL30108. 5.2.1 Clock Oscillator When selecting a Clock Oscillator, numerous parameters must be considered. These includes absolute frequency, frequency change over temperature, output rise and fall times, output levels, duty cycle and phase noise. 1 Frequency 20 MHz 2 Tolerance As required 3 Rise & Fall Time <10 ns 4 Duty Cycle 40% to 60% Table 5 - Typical Clock Oscillator Specification The output clock should be connected directly (not AC coupled) to the OSCi input of the ZL30108 and the OSCo output should be left open as shown in Figure 11. ZL30108 OSCi +3.3 V +3.3 V 20 MHz OUT GND 0.1 µF OSCo No Connection Figure 11 - Clock Oscillator Circuit 18 Zarlink Semiconductor Inc. ZL30108 5.2.2 Data Sheet Crystal Oscillator Alternatively, a Crystal Oscillator may be used. A complete oscillator circuit made up of a crystal, resistor and capacitors is shown in Figure 12. The accuracy of a crystal oscillator depends on the crystal tolerance as well as the load capacitance tolerance. Typically, for a 20 MHz crystal specified with a 32 pF load capacitance, each 1 pF change in load capacitance contributes approximately 9 ppm to the frequency deviation. Consequently, capacitor tolerances and stray capacitances have a major effect on the accuracy of the oscillator frequency. The crystal should be a fundamental mode type - not an overtone. The fundamental mode crystal permits a simpler oscillator circuit with no additional filter components and is less likely to generate spurious responses. The crystal specification is as follows. 1 Frequency 20 MHz 2 Tolerance As required 3 Oscillation Mode Fundamental 4 Resonance Mode Parallel 5 Load Capacitance As required 6 Maximum Series Resistance 50 Ω Table 6 - Typical Crystal Oscillator Specification ZL30108 20 MHz OSCi 1 MΩ OSCo 100 Ω 1 µH The 100 Ω resistor and the 1 µH inductor may improve stability and are optional. Figure 12 - Crystal Oscillator Circuit 19 Zarlink Semiconductor Inc. ZL30108 5.3 Data Sheet Power Up Sequence The ZL30108 requires that the 3.3 V is not powered after the 1.8 V. This is to prevent the risk of latch-up due to the presence of parasitic diodes in the IO pads. Two options are given: 1. Power-up 3.3 V first, 1.8 V later 2. Power up 3.3 V and 1.8 V simultaneously ensuring that the 3.3 V power is never lower than 1.8 V minus a few hundred millivolts (e.g., by using a schottky diode or controlled slew rate) 5.4 Reset Circuit A simple power up reset circuit with about a 300 us reset low time is shown in Figure 13. Resistor RP is for protection only and limits current into the RST pin during power down conditions. The reset low time is not critical but should be greater than 300 ns. ZL30108 +3.3 V R 10 kΩ RST RP 1 kΩ C 10 nF Figure 13 - Power-Up Reset Circuit 20 Zarlink Semiconductor Inc. ZL30108 6.0 Characteristics 6.1 AC and DC Electrical Characteristics Data Sheet Absolute Maximum Ratings* Parameter Symbol Min. Max. Units VDD_R -0.5 4.6 V VCORE_R -0.5 2.5 V 1 Supply voltage 2 Core supply voltage 3 Voltage on any digital pin VPIN -0.5 6 V 4 Voltage on OSCi and OSCo pin VOSC -0.3 VDD + 0.3 V 5 Current on any pin IPIN 30 mA 6 Storage temperature TST 125 °C 7 Package power dissipation PPD 195 mW 8 ESD rating VESD 2k V -55 * Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied. * Voltages are with respect to ground (GND) unless otherwise stated Recommended Operating Conditions* Characteristics 1 Supply voltage 2 Core supply voltage 3 Operating temperature Sym. Min. Typ. Max. Units VDD 2.97 3.30 3.63 V VCORE 1.62 1.80 1.98 V TA -40 25 85 °C Notes * Voltages are with respect to ground (GND) unless otherwise stated. DC Electrical Characteristics* Characteristics 1 Supply current with: OSCi = 0 V 2 3 OSCi = Clock Core supply current with: OSCi = 0 V 4 OSCi = Clock Sym. Min. Max. Units IDDS 2.5 7.0 mA outputs loaded with 30 pf IDD 43 mA Outputs unloaded ICORES 20 uA ICORES 18 mA 5 Schmitt trigger Low to High threshold point VCIH 1.47 1.85 V 6 Schmitt trigger High to Low threshold point VCIL 0.8 1.1 V 7 Input leakage current IIL -105 105 µA 21 Zarlink Semiconductor Inc. All device inputs are Schmitt trigger type. VI=VDD or 0 V ZL30108 Data Sheet DC Electrical Characteristics* Characteristics Sym. Min. 2.4 8 High-level output voltage VOH 9 Low-level output voltage VOL Max. Units 0.4 Notes V IOH = 8 mA for clock and framepulse outputs, 4 mA for status outputs V IOL = 8 mA for clock and framepulse outputs, 4 mA for status outputs * Supply voltage and operating temperature are as per Recommended Operating Conditions. * Voltages are with respect to ground (GND) unless otherwise stated. AC Electrical Characteristics* - Timing Parameter Measurement Voltage Levels (see Figure 14). Characteristics Sym. CMOS Units VT 1.5 V VHM 2.0 V 3 Rise and Fall Threshold Voltage Low VLM * Supply voltage and operating temperature are as per Recommended Operating Conditions. * Voltages are with respect to ground (GND) unless otherwise stated. 0.8 V 1 Threshold Voltage 2 Rise and Fall Threshold Voltage High Timing Reference Points V HM VT V LM ALL SIGNALS tIRF, tORF tIRF, tORF Figure 14 - Timing Parameter Measurement Voltage Levels. 22 Zarlink Semiconductor Inc. ZL30108 Data Sheet AC Electrical Characteristics* - Input timing for REF0 and REF1 references (see Figure 15). Characteristics Symbol Min. Typ. Max. Units 1 2 kHz reference period tREF2kP 483 500 516 µs 2 8 kHz reference period tREF8kP 120 125 128 µs 3 1.544 MHz reference period tREF1.5P 338 648 950 ns 4 2.048 MHz reference period tREF2P 263 488 712 ns 5 8.192 MHz reference period tREF8P 63 122 175 ns 6 16.384 MHz reference period tREF16P 38 61 75 ns 7 19.44 MHz reference period tREF8kP 38 51 75 ns 8 reference pulse width high or low tREFW 15 ns * Supply voltage and operating temperature are as per Recommended Operating Conditions. * Period Min/Max values are the limits to avoid a single-cycle fault detection. Short-term and long-term average periods must be within Out-ofRange limits. AC Electrical Characteristics* - Input to output timing for REF0 and REF1 references (see Figure 15). Characteristics Symbol Min. Max. Units 1 2 kHz reference input to F2ko delay tREF2kD 0 1.2 ns 2 2 kHz reference input to F8ko delay tREF2k_F8kD -27.2 -26.5 ns 3 8 kHz reference input to F8ko delay tREF8kD -0.3 2 ns 4 1.544 MHz reference input to F8ko delay tREF1.5_F8kD -1.1 0.9 ns 5 2.048 MHz reference input to F8ko delay tREF2_F8kD -1.1 0.9 ns 6 8.192 MHz reference input to F8ko delay tREF8_F8kD -0.6 0.8 ns 7 16.384 MHz reference input to F8ko delay tREF16_F8kD 29.0 30.6 ns 8 19.44 MHz reference input to C19o delay tREF19D 0.2 1.1 ns 9 19.44 MHz reference input to F8ko delay tREF19_F8kD -1.7 1 ns * Supply voltage and operating temperature are as per Recommended Operating Conditions. 23 Zarlink Semiconductor Inc. ZL30108 Data Sheet tREF<xx>P tREFW tREFW REF0/1 tREF<xx>D output clock with the same frequency as REF tREF8D, tREF<xx>_F8kD F8ko Figure 15 - Input to Output Timing AC Electrical Characteristics* - Output Timing (see Figure 16). Characteristics Sym. Min. Max. Units 1 C19o delay tC19D -1.0 0.5 ns 2 C19o pulse width low tC19L 25.0 25.8 ns 3 F2ko delay tF2kD 25.0 26.6 ns 4 F2ko pulse width high tF2kH 51.1 52 ns 5 F8ko pulse width high tF8kH 30.0 31.8 ns 7 Output clock and frame pulse rise or fall time (with 30 pF load) tORF 1.1 2.3 ns * Supply voltage and operating temperature are as per Recommended Operating Conditions. tF8kH F8ko tC19L tC19D C19o tF2D tF2kH F2ko Figure 16 - SONET/SDH Output Timing Referenced to F8ko 24 Zarlink Semiconductor Inc. ZL30108 Data Sheet AC Electrical Characteristics* - OSCi 20 MHz Master Clock Input Characteristics 1 Sym. Oscillator Tolerance 2 Min. Typ. Max. Units -20 +20 ppm OOR_SEL=0 -32 +32 ppm OOR_SEL=1 40 60 % 4 Duty cycle 5 Rise time 10 ns 6 Fall time 10 ns Notes * Supply voltage and operating temperature are as per Recommended Operating Conditions. 6.2 Performance Characteristics Performance Characteristics* - Functional Characteristics Min. Typ. Max. Units Notes 1 Holdover accuracy 0.01 ppm 2 Holdover stability NA ppm Determined by stability of the 20 MHz Master Clock oscillator 3 Capture range -130 +130 ppm The 20 MHz Master Clock oscillator set at 0.ppm 4 Reference Out of Range Threshold (including hysteresis) -64 -83 +64 +83 ppm The 20 MHz Master Clock oscillator set at 0 ppm and OOR_SEL=1 -40 -52 +40 +52 ppm The 20 MHz Master Clock oscillator set at 0 ppm and OOR_SEL=0 6 Lock Time 7 14 Hz Filter 1.5 s input reference = 2 kHz, ±100 ppm frequency offset 8 29 Hz Filter 1 s input reference ≠ 2 kHz, ±100 ppm frequency offset Output Phase Continuity (MTIE) 11 Reference switching 13 ns 12 Switching from Normal mode to Automatic Holdover mode 0 ns 13 Switching from Automatic Holdover mode to Normal mode 13 ns * Supply voltage and operating temperature are as per Recommended Operating Conditions. 25 Zarlink Semiconductor Inc. ZL30108 Data Sheet Performance Characteristics*: Measured Output Jitter - GR-253-CORE and T1.105.03 conformance Telcordia GR-253-CORE and ANSI T1.105.03 Jitter Generation Requirements Signal Jitter Measurement Filter Limit in UI (1 UI = 6.4 ns) Equivalent limit in time domain ZL30108 Maximum Jitter Generation Units OC-3 Interface 1 C19o 2 3 65 kHz to 1.3 MHz 0.15 UIpp 0.96 0.22 nspp 12 kHz to1.3 MHz (Category II) 0.1 UIpp 0.64 0.22 nspp 64 24 psrms 9.65 0.22 nspp 500 Hz to 1.3 MHz 0.01 UIrms 1.5 UIpp * Supply voltage and operating temperature are as per Recommended Operating Conditions Performance Characteristics*: Measured Output Jitter - G.813 conformance (Option 1 and Option 2 ITU-T G.813 Jitter Generation Requirements Signal Jitter Measurement Filter Limit in UI (1 UI = 6.4 ns) Equivalent limit in time domain ZL30108 Maximum Jitter Generation Units STM-1 Option 1 Interface 1 C19o 2 65 kHz to 1.3 MHz 0.1 UIpp 0.64 0.22 nspp 500 Hz to 1.3 MHz 0.5 UIpp 3.22 0.22 nspp 0.1 UIpp 0.64 0.22 nspp STM-1 Option 2 Interface 3 C19o 12 kHz to1.3 MHz * Supply voltage and operating temperature are as per Recommended Operating Conditions Performance Characteristics* - Unfiltered Intrinsic Jitter Max. [nspp] Signal 1 C19o (19.44 MHz) 0.5 2 F8ko (8 kHz) 0.5 3 F2ko (2 kHz) 0.5 * Supply voltage and operating temperature are as per Recommended Operating Conditions. 26 Zarlink Semiconductor Inc. Notes For more information about all Zarlink products visit our Web Site at www.zarlink.com Information relating to products and services furnished herein by Zarlink Semiconductor Inc. or its subsidiaries (collectively “Zarlink”) is believed to be reliable. However, Zarlink assumes no liability for errors that may appear in this publication, or for liability otherwise arising from the application or use of any such information, product or service or for any infringement of patents or other intellectual property rights owned by third parties which may result from such application or use. Neither the supply of such information or purchase of product or service conveys any license, either express or implied, under patents or other intellectual property rights owned by Zarlink or licensed from third parties by Zarlink, whatsoever. Purchasers of products are also hereby notified that the use of product in certain ways or in combination with Zarlink, or non-Zarlink furnished goods or services may infringe patents or other intellectual property rights owned by Zarlink. This publication is issued to provide information only and (unless agreed by Zarlink in writing) may not be used, applied or reproduced for any purpose nor form part of any order or contract nor to be regarded as a representation relating to the products or services concerned. The products, their specifications, services and other information appearing in this publication are subject to change by Zarlink without notice. No warranty or guarantee express or implied is made regarding the capability, performance or suitability of any product or service. Information concerning possible methods of use is provided as a guide only and does not constitute any guarantee that such methods of use will be satisfactory in a specific piece of equipment. It is the user’s responsibility to fully determine the performance and suitability of any equipment using such information and to ensure that any publication or data used is up to date and has not been superseded. Manufacturing does not necessarily include testing of all functions or parameters. These products are not suitable for use in any medical products whose failure to perform may result in significant injury or death to the user. All products and materials are sold and services provided subject to Zarlink’s conditions of sale which are available on request. Purchase of Zarlink’s I2C components conveys a licence under the Philips I2C Patent rights to use these components in and I2C System, provided that the system conforms to the I2C Standard Specification as defined by Philips. Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc. Copyright Zarlink Semiconductor Inc. All Rights Reserved. TECHNICAL DOCUMENTATION - NOT FOR RESALE