特性
- Clock frequency translator for Synchronous Ethernet applications
- One single-ended output (LVCMOS or LVTTL levels), 16Ω output impedance
- Differential input pair (CLK, nCLK) accepts LVPECL, LVDS, LVHSTL, SSTL, HCSL input levels
- Supports input clock frequencies of: 125MHz, 156.25MHz or 161.1328MHz
- Generates a 25MHz output clock signal
- Internal resistor bias on nCLK pin allows the user to drive CLK input with external single-ended (LVCMOS/LVTTL) input levels
- Internal PLL is optimized for low cycle-to-cycle jitter at the output
- Full 3.3V or 2.5V supply voltage
- -40°C to 85°C ambient operating temperature
- Available in lead-free (RoHS 6) package
描述
The 840271I is a PLL-based Frequency Translator intended for use in telecommunication applications such as Synchronous Ethernet. The internal PLL translates Ethernet clock frequencies such as 125MHz (1Gb Ethernet), 156.25MHz (10GbE XAUI) and 161.1328MHz (10Gb Ethernet) to an output frequency of 25MHz. The PLL does not any require external components. The input frequency is selectable by a 2-pin interface. The 840271I is optimized for low cycle-to-cycle jitter on the 25MHz output signal. The input of the device accepts differential (LVPECL, LVDS, LVHSTL, SSTL, HCSL) or single-ended (LVCMOS) signals. The extended temperature range supports telecommunication and networking equipment requirements. The 840271I uses a small RoHS 6, 8-pin TSSOP package and is an effective solution for space-constrained applications.
