| PIN | NAME | FUNCTION |
| 25 | BIAS | Laser Bias Current Output |
| 29 | OUT+ | Positive Mod ulation-Current Output. IMOD flows throug h this pad when input data is high. |
| 30 | OUT- | Negative Modulation-Current Output. IMOD flows through this pad when input data is low. |
| 35 | MD | Monitor Diode Input. Connect this pad to a monitor photodiode anode. A capacitor to ground is required to filter high-speed AC monitor photocurrent. |
| 34, 36, 40 | GND3 | Ground for APC |
| 37 | Vcc3 | Power Supply for APC |
| 38 | CAPC | A capacitor connected from this pad to ground controls the dominant pole of the APC feed- back loop. (CAPC = O.lpF) |
| 44 | APCSET | A resistor connected from this pad to ground sets the desired average optical power. Connect 100kl from this pad to ground if APC is not used. |
| 46 | MODSET | A resistor connected from this pad to ground sets the desired modulation current. |
| 47 | BIASMAX | A resistor connected from this pad to ground sets the maximum bias current. The APC function can subtract from this maximum value, but can not add to it. |
| 48 | Vcc2 | Power Supply for internal reference |
| | |