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Infineon Technologies IMIFS731BZB — Clock & Timing ICs

IMIFS731BZB Spread Spectrum Clock Generator, PLL, 4.5V-5.5V

MPNIMIFS731BZB
End of Life

Spread Spectrum Clock Generator, PLL Yes, 1 Circuit, 1:2 Ratio, CMOS/TTL Input/Output, 4.5V~5.5V Supply, 0°C~70°C, 8-SOIC Package.

$0.75Ref. price · indicative, final on quote
Packaging8-SOIC (0.154", 3.90mm Width)
RoHSNot applicable
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

IMIFS731BZB specifications
ParameterValue
TypeSpread Spectrum Clock Generator
MountingSurface Mount
Supply voltage4.5V ~ 5.5V
Operating temperature0°C ~ 70°C (TA)
PLLYes
InputCMOS, TTL
OutputCMOS, TTL
PackageBulk
Case8-SOIC (0.154\", 3.90mm Width)
Divider (Multiplier)Yes/No
Number of circuits1
Ratio - Input:Output1:2
Differential - Input:OutputNo/No

Product details

What this clock generator does for your board

The IMIFS731BZB is a spread spectrum clock generator with an integrated PLL, designed to reduce electromagnetic interference (EMI) by spreading the output clock energy across a small frequency band rather than concentrating it at a single peak. It accepts a single CMOS or TTL input clock and delivers two buffered copies (1:2 ratio) at the same frequency, also in CMOS or TTL levels. The part runs from a 4.5V to 5.5V supply and is specified over the commercial temperature range of 0°C to 70°C.

Supply voltage and temperature — fit for the BOM

The 4.5V to 5.5V supply range means this part is strictly a 5V device. If your board runs on 3.3V, you will need a separate regulator or a different clock generator.

PLL and spread spectrum — the EMI play

The integrated PLL (yes, it is listed) is the active core that generates the spread-spectrum modulation. The spread-spectrum function is the main reason to pick this part: it reduces peak EMI emissions at the fundamental and harmonics, which can help pass FCC or CISPR radiated-emission tests without adding ferrite beads or shielding. The 1:2 fan-out gives you two synchronous copies of the input clock — enough to drive a small logic cluster or two loads, but not a multi-drop bus.

Package and handling — field-service friendly

The 8-SOIC (0.154" wide, 3.90mm body) is a common, easy-to-solder footprint. No hot-air station needed — a standard soldering iron and some wick will swap it on site. Orientation is clear from the pin-1 notch. No special ESD precautions beyond the usual wrist strap.

Frequently asked questions

What is the equivalent of IMIFS731BZB?

The CY2305SXI-1HT is a functionally similar spread-spectrum clock generator with a PLL, but it runs on 3.0V, offers a 1:5 fan-out, and is rated -40°C to 85°C. It is not a pin-for-pin drop-in replacement — the supply voltage and output count differ.

What is the function of IMIFS731BZB?

It is a spread spectrum clock generator with an integrated PLL. It takes one CMOS or TTL input clock and outputs two buffered copies at the same frequency, spreading the energy to reduce EMI.