How to find the right Delay Lines AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Delay Lines
- Fixed or programmable
- Fixed tapped delay lines give set delays per tap, while programmable parts set delay by parallel pins or a serial interface Programmable parts let you calibrate in-circuit, and fixed parts are simpler and need no control logic.
- Total delay and step resolution
- Total range must cover your maximum skew, and step size must be finer than the timing margin you are trimming These two numbers define whether the part can actually correct your timing problem.
- Logic family
- Match TTL/CMOS or ECL/PECL/LVPECL to the signal path ECL-family delay chips serve high-speed differential paths and cannot be driven directly from CMOS logic.
- Delay accuracy over temperature and voltage
- Check the tolerance of each tap and the drift across the operating range, not just nominal delay Delay-line error accumulates and drifts, which can eat the timing margin the part was added to create.
- Input pulse and rise-time limits
- Check minimum pulse width and maximum input frequency Pulses narrower than the spec get distorted or swallowed inside the line.
Brands that matter
- Analog Devices (Maxim/Dallas): Silicon fixed and programmable delay lines inherited from Dallas Semiconductor and Maxim.
- onsemi: Programmable ECL-family delay chips for high-speed differential timing.
- Microchip: High-speed programmable delay parts carried over from Micrel.
- Data Delay Devices: Specialist maker of fixed and programmable delay line modules.
What to avoid
- Obsolete through-hole delay modules sold without a datasheet or date code.
- Using a delay line where a PLL phase adjustment or FPGA I/O delay would do the job more accurately.
- Mixing ECL-family delay chips into CMOS designs without proper level translation and termination.
Questions
Can I just use a chain of gates or an RC network instead?
For rough delays yes, but gate and RC delays vary a lot with voltage, temperature and part lot, which is what dedicated delay lines are built to control.