SY88349NDLMG Microchip

SY88349NDL 2.5Gbps Burst-Mode Limiting Amplifier with Ultra-Fast Signal Assert Timing General Description Features The SY88349NDL is a high-sensitivity, burst-mode <5ns SD assert (LOS deassert) time capable limiting post amplifier designed for optical line Proprietary noise discriminator feature terminal (OLT) receiver applications. The SY88349NDL Option to AUTO RESET or manual RESET LOS/SD satisfies the strict timing restrictions of the GPON output standards by providing ultra-fast loss-of-signal (LOS) or Selectable LOS/SD option Signal-Detect (SD) output. Auto reset and manual reset options are provided to control LOS/SD output timing. For Up to 2.5Gbps operation increased flexibility, this device also includes an option to Low-noise CML data outputs select between LOS or SD output. The device can be 5mVpp input sensitivity connected to burst-mode capable transimpedance High-sensitivity LOS/SD detect amplifiers (TIAs) using AC or DC coupling. LVTTL LOS/SD output with an external pull-up resistor The SY88349NDL generates a high-gain LOS or SD Squelching function to disable output LVTTL output. A programmable LOS/SD level set pin (LOS/SD ) sets the sensitivity of the input amplitude LVL Programmable LOS/SD level set (LOS/SD ) LVL detection. When LOS/SD SEL pin is left open or tied to Single 3.3V power supply V , JAM is active high, SD is selected and asserts high if CC Available in a 16-pin (3mm 3mm) QFN package the input amplitude rises above the threshold sets by LOS/SD and de-asserts low otherwise. When LOS/SD LVL SEL pin is set low or tied to GND, JAM is active low, LOS Applications is selected and asserts low if the input amplitude rises XGPON.1/GEPON/GPON above the threshold sets by LOS/SD and de-asserts LVL high otherwise. The LOS/SD output can be fed back to the Gigabit Ethernet JAM input to maintain output stability under an invalid Fibre Channel signal conditions. Typically, 4dB 5dB SD hysteresis is OC-3/12/24/48 SONET/SDH provided to prevent chattering. High-gain line driver and line receiver The SY88349NDL also features a selectable proprietary Low-gain TIA interface noise discriminator that aids by filtering out input signals that do not qualify as a 2.5Gbps GPON preamble signal in the initial startup phase. This feature minimizes false SD Markets asserts that can be triggered by random noise. FTTH The SY88349NDL operates from a single +3.3V power Datacom/Telecom supply, over temperatures ranging from 40 C to +85C. Optical transceiver With its wide bandwidth and high gain, signals up to 2.5Gbps and as small as 5mVpp can be amplified to drive devices with CML inputs. Data sheets and support documentation can be found on Micrels web site at www.micrel.com. M9999-010212-C January 2012 2 hbwhelp micrel.com or (408) 955-1690 Micrel, Inc. SY88349NDL Ordering Information Part Number Package Type Operating Range Package Marking 349N with SY88349NDLMG Lead-Free 16-Pin 3mm 3mm QFN 40C to +85C Pb-Free Bar-Line Indicator (1) 349N with SY88349NDLMGTR Lead-Free 16-Pin 3mm 3mm QFN 40C to +85C Pb-Free Bar-Line Indicator Note: 1. Tape & Reel. Pin Configuration 16-Pin 3mm 3mm QFN (QFN-16) Pin Description Pin Number Pin Name Pin Function 1, 4 DIN, /DIN Data Inputs. If AC-coupled, terminate each pin to V with 50. REF 2 VREF Reference Voltage Output. Typically V 1.3V. CC 3, 11, 8 GND Device Ground. LVTTL Input. This pin is internally connected to a 25k pull-up resistor and defaults to HIGH. When this pin is LOW or tied to ground, the /AUTO RESET function is enabled and SD de- 10 /AUTO RESET asserts or LOS asserts within 100ns (typical) after the last high-to -low transition of the burst input. When this pin is left floating or not connected, the AUTO RESET function is disabled and the SD de-assert or LOS assert must be forced by using the manual RESET function. 5, 16 VCC Positive Power Supply. M9999-010212-C January 2012 3 hbwhelp micrel.com or (408) 955-1690