L10881_15 Datasheet, PDF (2/3 Pages) Hamamatsu Corporation – Red LED for optical link

Red LED for optical link
L10881
Electrical and optical characteristics (Ta=25 °C)
Parameter
Symbol
Condition
Min.
Typ.
Max.
Unit
Forward voltage
VF
IF=20 mA
-
1.9
2.4
V
Peak emission wavelength
λp
IF=20 mA
640
650
665
nm
Spectral half width (FWHM)
Δλ
IF=20 mA
-
-
25
nm
Fiber coupled optical power
Po
*³
-4.5
-2
+0.5
dBm
Pulse distortion
ΔT
*³
-2.5
-
2.5
ns
Cut-off frequency
fc
IF=20 mA ±1 mAp-p
60
70
-
MHz
*3: Measured with the recommended driver circuit shown below.
Recommended driver circuit
Vcc
Icc
0.1 mF
0.1 µF R2
SIGNAL INPUT
1 ^{14 74ACT08} R1
2
3
7
C1
L10881(X)
1
2
3
4
KLEDC0047EA
Input is a pseudo-random bi-phase signal at 156 Mbps (NZR signal conversion).
Average value (duty ratio 50 %) measured by using a plastic fiber of φ1 mm. SI-POF and NA=0.5 (GH4001 made by Mitsubishi Rayon).
Vcc=5.0 V, R1=100 Ω, R2=300 kΩ, C1=20 pF
Note:
· A bypass capacitor (0.1 μF) and another capacitor (4.7 μF) are connected between Vcc and GND at a position within 3 mm from the lead.
· The center of the optical fiber is aligned with the center of the lens on the package. The distance between the fiber end and the lens is 0.1 mm.
· When using optical fibers with small core diameter, the fiber-coupled optical output power may vary.
Emission spectrum
(Typ. Ta=25 °C, IF=20 mA)
120
100
80
60
40
20
0
600
620
640
660
680
Wavelength (nm)
700
KLEDB0321EA
Forward current vs. forward voltage
(Typ. Ta=25 °C, IF=20 mA)
50
40
30
20
10
0
0
0.5 1.0 1.5 2.0 2.5 3.0
Forward voltage (V)
KLEDB0322EA
2