DS1089L Maxim Integrated Products, DS1089L Datasheet
DS1089L
Available stocks
Related parts for DS1089L
DS1089L Summary of contents
Page 1
... Rev 1; 9/05 3.3V Center Spread-Spectrum EconOscillator™ General Description The DS1089L is a clock generator that produces a spread spectrum (dithered) square-wave output of fre- quencies from 130kHz to 66.6MHz. The DS1089L is shipped from the factory programmed at a specific fre- quency. The DS1089L is pin-for-pin compatible with the DS1087L, however, the DS1089L dithers at equal per- centages above and below the center frequency ...
Page 2
Center Spread-Spectrum EconOscillator™ ABSOLUTE MAXIMUM RATINGS Voltage on V Relative to Ground.......................-0.5V to +6.0V CC PDN, OE, SDA, Voltage on SPRD, SCL Relative to Ground* ........................-0. Operating Temperature Range ...........................-40°C to +85°C *This voltage must not exceed ...
Page 3
Center Spread-Spectrum EconOscillator™ MASTER OSCILLATOR CHARACTERISTICS (V = +2.7V to +3.6V -40°C to +85° PARAMETER SYMBOL Internal Master Oscillator Frequency ∆f Master Oscillator Frequency Tolerance Voltage Frequency Variation Temperature Frequency Variation (Note 4) Dither Frequency ...
Page 4
Center Spread-Spectrum EconOscillator™ AC ELECTRICAL CHARACTERISTICS— +2.7V to +3.6V -40°C to +85°C, unless otherwise noted. Timing referenced PARAMETER SYMBOL SCL Clock Frequency f Bus Free Time Between Stop and t Start ...
Page 5
Center Spread-Spectrum EconOscillator™ 3.3V +25°C, unless otherwise noted ACTIVE SUPPLY CURRENT vs. SUPPLY VOLTAGE +25°C, A 66MHz OUTPUT UNLOADED 50MHz 130kHz 33MHz 2 0 2.7 3.0 3.3 ...
Page 6
Center Spread-Spectrum EconOscillator™ 3.3V +25°C, unless otherwise noted DUTY CYCLE vs. SUPPLY VOLTAGE +25° 66MHz 50MHz 33MHz 130kHz 48 2.7 3.0 3.3 3.6 SUPPLY VOLTAGE ...
Page 7
... Prescaler 0011 0100 0101 0110 8 will be decod- 0111 1000 Equation 1 f MOSC = 1111 x 2 _____________________________________________________________________ Block Diagram DS1089L OUTPUT CONTROL PRESCALER f f SYNCED OSC MOSC OUTPUT DIVIDE BUFFER 8, 16, 32, 64, 128, OR 256 f MOSC PRESCALER SETTING OUTPUT CONFIGURATION ...
Page 8
... Dither Generator The DS1089L has the ability to reduce radiated emis- sion peaks. The output frequency can be dithered by ±1%, ±2%, ±4%, or ±8% symmetrically around the pro- grammed center frequency. Although the output fre- quency changes when the dither is enabled, the duty cycle does not change ...
Page 9
... and selecting f MOSC dither frequency would be 19.531kHz. Register Summary The DS1089L registers are used to change the dither amount, output frequency, and slave address. A bit summary of the registers is shown in Table 4. Once pro- grammed into EEPROM, the settings only need to be reprogrammed desired to reconfigure the device ...
Page 10
Center Spread-Spectrum EconOscillator™ WRITE EE Command The WRITE EE command is useful in closed-loop appli- cations where the registers are frequently written. In applications where the register contents are frequently written, the WC bit should be set to 1 ...
Page 11
... These capacitors should be placed as close to the V SCL and SDA cannot be left floating even in stand- alone mode. If the DS1089L will never need to be pro- grammed in-circuit, including during production testing, SDA and SCL can be connected high. ____________________________________________________________________ ...
Page 12
... XTL1/OSC1 2-WIRE INTERFACE XTL2/OSC2 V CC MICROPROCESSOR *SDA AND SCL CAN BE CONNECTED DIRECTLY HIGH IF THE DS1089L NEVER NEEDS TO BE PROGRAMMED IN-CIRCUIT, INCLUDING DURING PRODUCTION TESTING. TRANSISTOR COUNT: 5985 SUBSTRATE CONNECTED TO GROUND SCL 8 7 SDA For the latest package outline information www ...