DS1077LU-66+

Overview

The DS1077LU-66+ is a dual-output, programmable fixed-frequency oscillator from the DS1077L series. It operates on a single 2.7V to 3.6V supply and requires no external components. The device features an internal master oscillator factory-trimmed to 66.666MHz. Two synchronous outputs (OUT0 and OUT1) provide frequencies ranging from 4.87kHz to 66.666MHz via on-chip prescalers and dividers. Frequency settings are stored in nonvolatile EEPROM memory. The unit supports a 2-wire serial interface for in-circuit programming and includes power-down mode capabilities.

Feature Summary

• Dual low-jitter synchronous outputs with user-adjustable submultiples of the master frequency
• 2-wire serial interface for on-the-fly programming of prescalers and dividers
• Nonvolatile EEPROM storage for frequency settings and control registers
• Single 2.7V to 3.6V supply operation with power-down mode

Applications

• Processor-controlled frequency synthesizers
• Standalone clock generation for digital systems
• Portable equipment requiring minimal board area

Procurement Notes

Verify the package type matches the 'U' suffix for 8-pin 118mil µSOP. Confirm the frequency option corresponds to the '-66' designation for 66.666MHz master frequency. Ensure compatibility with the required 2-wire serial bus voltage levels and check for any specific environmental compliance requirements if applicable.

Selection Notes

Select this component when a dual-output clock source is needed with precise frequency division capabilities. The DS1077LU-66+ is suitable for applications requiring ±0.5% initial tolerance and ±1.25% variation over temperature and voltage. Consider the 8-pin µSOP package for space-constrained designs compared to the larger SO package options.

Part Context

The DS1077LU-66+ belongs to the DS1077L EconOscillator/Divider family. The 'LU' suffix indicates the 8-pin 118mil µSOP package variant, while 'Z' denotes the 150mil SO package. The '-66' specifies the 66.666MHz master frequency option within the standard frequency lineup that also includes 40MHz, 50MHz, and 60MHz variants.

Replacement Considerations

Direct pin-compatible replacements include other DS1077Lx-66 variants such as DS1077Z-66+ for the SO package. For different frequency requirements, consider DS1077LU-40+, DS1077LU-50+, or DS1077LU-60+. Verify package dimensions and electrical characteristics match before substitution.

FAQ

How are the output frequencies determined?

Output frequencies are determined by the internal master oscillator divided by programmable prescalers (P0 and P1) and a divider (N). These values are set via the 2-wire serial interface and stored in nonvolatile EEPROM.

What is the function of the CTRL0 and CTRL1 pins?

CTRL0 and CTRL1 are multifunctional input pins configurable as output enables or power-down controls. Their functions are determined by the EN0, SEL0, PDN0, and PDN1 register bits.

Can the device be used without connecting the serial interface?

Yes, for fixed-frequency applications, preprogrammed devices can be used without connecting to the serial interface. The frequency settings are retained in the nonvolatile memory upon power-up.