Cypress RoboClock™ CY7B991-5JIT, PLL-based fanout buffer / zero delay buffer, 80 MHz max, 1:8 CMOS fanout, 4.5-5.5V supply, -40 to 85°C, 32-PLCC (J-Lead), surface mount.
| Parameter | Value |
|---|---|
| Type | Fanout Buffer (Distribution), Zero Delay Buffer |
| Series | RoboClock™ |
| Mounting | Surface Mount |
| Supply voltage | 4.5V ~ 5.5V |
| Frequency - max | 80MHz |
| Operating temperature | -40°C ~ 85°C (TA) |
| PLL | Yes |
| Input | CMOS |
| Output | CMOS |
| Package | Bulk |
| Case | 32-LCC (J-Lead) |
| Divider (Multiplier) | Yes/No |
| Number of circuits | 1 |
| Ratio - Input:Output | 1:8 |
| Differential - Input:Output | No/No |
The Cypress CY7B991-5JIT is a PLL-based clock fanout buffer from the RoboClock family. It takes one CMOS input and distributes it to eight CMOS outputs with zero-delay alignment. No differential I/O.
Housed in a 32-lead PLCC with J-leads, body dimensions 11.43 x 13.97 mm. Surface-mount.
The part is RoHS non-compliant.
The manufacturer lists the CY7B991-5JIT as Active. No end-of-life notice or last-time-buy window is in effect. It can be specified into new designs without obsolescence risk.
No. The supply voltage range is 4.5 V to 5.5 V, and the input is CMOS-level referenced to that supply. A 3.3 V logic signal will not reliably drive the input. Use level translation or select a 3.3 V-rated clock buffer.
The Cypress CY2305SXI-1HT is a similar PLL-based fanout buffer but runs on 3.3 V and has a 1:5 fanout ratio, not 1:8. It is not a pin-for-pin replacement — the PLCC footprint and 5 V supply differ. For a functional equivalent at 5 V with 1:8 fanout, the best path is to source the original CY7B991-5JIT or check the RoboClock family for a 5 V variant with the same PLCC pinout.