2
SY88902
Micrel
Pin Function
VCC Most positive power supply input, +5V for PECL
operation.
GND Ground
DIN, /DIN These differential PECL 100K compatible inputs
receive NRZ data.
/EN This PECL 100K compatible input enables
Laser Driver. Modulation current goes to zero
when asserted HIGH.
OUT, /OUT Open collector outputs from the modulation
buffer drive these differential current outputs.
VREF Voltage reference for use with RSET.
RSET An external resistor sets up the source current
for modulation Imod.
D D /EN OUT (2) /OUT
LHLHL
HLLLH
XXHHL
NOTES:
1. L = LOW, H = HIGH, X = don't care
2. H = IOUT = OmA
PIN NAMES TRUTH TABLE(1)
Symbol Rating Value Unit
VCC Power Supply Voltage 0 to +7.0 V
VIInput Voltage 0 to VCC V
IOOutput Current 25 mA
TAOperating Temperature Range 0 to +85 °C
Tstore Storage Temperature Range –55 to +125 °C
Ptot Power Dissipation 250 mW
ABSOLUTE MAXIMUM RATINGS(1)
NOTE:
1. Permanent device damage may occur if ABSOLUTE MAXIMUM RATINGS are exceeded. This is a stress rating only and functional operation is not implied
at conditions other than those detailed in the operational sections of this data sheet. Exposure to ABSOLUTE MAXIMUM RATlNG conditions for extended
periods may affect device reliability.
Symbol Rating Value Unit
VCC Power Supply Voltage +4.5 to +5.5 V
REXT Resistor to Dissipate Power 10 to 50 Ω
RSER Laser Diode Serial Resistor 0 to 50 Ω
RSET Resistor to Adjust Current 1500 to 50,000 Ω
ΘJA Thermal Resistance of Package to Ambient(2) 206 °C/W
COUT Capacitance on OUT + /OUT 2.5 typical pf
OPERATIONING CONDITIONS(1)
NOTES:
1. The voltage drop across REXT and RSER plus Laser Diode should not be greater than 2V.
2. Still air without heatsink.