8745BI-21 Datasheet Text
1:1 Differential-to-LVDS Zero Delay Clock Generator
8745BI-21
Datasheet
General Description
Features
The 8745BI-21 is a highly versatile 1:1 LVDS Clock Generator. The 8745BI-21 has a fully integrated PLL and can be configured as a zero delay buffer, multiplier or divider, and has an output frequency range of 31.25MHz to 700MHz. The Reference Divider, Feedback Divider and Output Divider are each programmable, thereby allowing for the following output-to-input frequency ratios: 8:1, 4:1, 2:1, 1:1, 1:2, 1:4, 1:8. The external feedback allows the device to achieve “zero delay” between the input clock and the output clock. The PLL_SEL pin can be used to bypass the PLL for system test and debug purposes. In bypass mode, the reference clock is routed around the PLL and into the internal output dividers.
Pin Assignments
CLK 1 nCLK 2
MR 3 nFB_IN 4
FB_IN 5 SEL2 6 VDDO 7 nQFB 8
QFB 9 GND 10
20 SEL1 19 SEL0
18 VDD 17 PLL_SEL 16 VDDA 15 SEL3 14 GND 13 Q 12 nQ 11 VDDO
8745BI-21
- One differential LVDS output designed to meet or exceed the requirements of ANSI TIA/EIA-644 One differential feedback output pair
- Differential CLK, nCLK input pair
- CLKx, nCLKx pair can accept the following differential input levels: LVPECL, LVDS, LVHSTL, HCSL, SSTL
- Output frequency range: 31.25MHz to 700MHz
- Input frequency range: 31.25MHz to 700MHz
- VCO range: 250MHz to 700MHz
- External feedback for “zero delay” clock regeneration with configurable frequencies
- Programmable dividers allow for the following output-to-input frequency ratios: 8:1, 4:1, 2:1, 1:1, 1:2, 1:4, 1:8
- Cycle-to-cycle jitter: 30ps (maximum)
- Output skew: 40ps (maximum)
- Static phase offset: 25ps ± 125ps
- Full 3.3V supply voltage
- -40°C to 85°C ambient operating temperature
- Available in lead-free (RoHS 6)...