SY88216LMG

SY88216LMG Features

• 2.4V minimum laser compliance voltage • Operation up to 2.5Gbps • Fast burst mode enable/disable delay • Modulation current up to 85mA • Bias current up to 70mA • • Safety features • Power monitoring • Available in 24-pin (4mm x 4mm) QFN packageInfinite bias current hold time between bursts

SY88216LMG General Description

The SY88216L is a single supply 3.3V burst mode laserdriver for A-PON, B-PON, EPON, GE-PON, and G-PONapplications with data rates from 155Mbps up to 2.5Gbps.The driver can deliver modulation current up to 85mA, andprovides a high compliance voltage that makes it suitablefor high-current operation with the laser DC-coupled to it.All support documentation can be found on Micrel’s website at: www.micrel.com.

SY88216LMG Applications

• Multi-rate burst mode applications: A-PON, B-PON,G-PON, E-PON, GE-PON

SY88216LMG Pin Description

Pin NumberPin NamePin FunctionSY88216L23567910121314161720222324DIN+DIN-BEN+BEN-/ENOSCNon-inverting input data. Internally terminated with 50Ω to a reference voltage.Inverting input data. Internally terminated with 50Ω to a reference voltage.Non-inverting burst enable. Accepts any input, single-ended or differential: TTL/CMOS,LVPECL, CML, LVDS, HSTL, and SSTL. BEN requires an external termination. See Figure 2.Inverting burst enable. Accepts any input, single-ended or differential: TTL/CMOS, LVPECL,CML, LVDS, HSTL, and SSTL. BEN requires an external termination. See Figure 2.Active low TTL/CMOS. Internally pulled-up. Pull-down with a 22kΩ or lower resistance orapply a low level signal (<0.8 V) to enable bias and modulation. Keep floating or apply a highlevel (>2 V) to disable.Internal oscillator setting option. Install a 0Ω resistor from this pin to VCC or leave it open toset the frequency. Refer to the frequency table./APCFAULTIndicates APC failure when low. Active low TTL/CMOS.PWRMONPower Monitor. Provides a current which is proportional to the sum of bias current and half ofmodulation current. Install a resistor between this pin and GND to convert that current to avoltage.BIAS-BIAS+MOD+MOD-MDBIASMAXMODSETAPCSETInverting laser bias current output. Pull-up to VCC with a resistor.Non-inverting laser bias current output, sources current when BEN is high. Connect to thecathode of the laser through a resistor.Non-inverted modulation current output. Provides modulation current when input data ispositive.Inverted modulation current output. Provides modulation current when input data is negative.Input from the laser monitoring photodiode. Connect to the anode of the photodiode for APCoperation.Install a resistor between this pin and GND to set the maximum bias current for the closedloop operation. The APC loop controls the bias current up to the level of BIASMAX. When thebias current reaches the maximum value set through this pin, the driver continues to sink acurrent equal to this maximum. For open loop operations, this pin sets the bias current.Modulation current setting and control. The modulation current is set by installing an externalresistor from this pin-to-ground or using a current source.Bias current setting and control. The bias current is set by installing an external resistor fromthis pin to ground or using a current source. Connect a 50K resistor-to-GND for open loopoperation.8, 11,19GNDGround. Ground and exposed pad must be connected to the plane of the most negativepotential.1, 4, 15, 18, 21VCCSupply Voltage. Bypass with a 0.1µF//0.01µF low ESR capacitor as close to VCC pin aspossible.