SPFMIT302 Avago Technologies, SPFMIT302 Datasheet - Page 3

• Manufacturer Part Number: SPFMIT302
• Description: Plastic Fiber Optic Transmitter For Most
• Manufacturer: Avago Technologies

Pulse Width Variation (t
The SPF MIT3 02 generates negative Puls Width Distortion. This means the optical output signal is shortened compared
to the electrical input signal. Therefore the parameters t
Layer Rev 1.0 (MOST SPL Rev. 1.0) either at the electrical input signal (SP1 in the MOST SPL Rev. 1.0) or at the optical
output signal (SP2 in the MOST SPL Rev. 1.0). This characteristic is shown in the following table.
a
b
Based on this table, the MOST System may be considered by two aspects:
a) In order to meet the MOST SPL Rev 1.0 at SP2 the t
b) If the MOST SPL Rev. 1.0 is met regarding t
DC Characteristics
Parameter
Low Level Input Voltage
High Level Input Voltage
Input Leakage Current
(V
Input Capacitance
Input Resistance
Supply Current (Rext = 15 kOhm) ON state,
biphase coded data
Supply Current (Rext = 15 kOhm) OFF state
Notes:
1. The current through the LED and therefore the optical output power and overall power consumption depends on the settings of R
2. The transmitter jumps to low power mode after TX DATA is low for max. 18µs If the transmitter is in low power mode it is switched ON 5µs (max.)
3
CC
MOST SPL Rev. 1.0. This can be achived e.g. by using OS8104 as MOST transceiver chip.
shortened. Within a MOST System, this characteristic can be compensated by the optical receiver which detects the
signal at SP3. For this compensation, the optical receiver has to be specified in a range which is smaller than the
range described in the MOST SPL Rev. 1.0. For a detailed evaluation of system behavior, see paper “OS8300 Revision
J behavior on SP2 (optical output signal)” from Oasis SiliconSystems.
nominal value for R
Important: The external resistor of Rext must be within the range of 13.5K to 33K. For values of Rext out of this range functionality may not be
given over the whole temperature range and the device lifetime. Using values below 13K for Rext can damage the transmitter.
after TX DATA starts toggling.
=5.0V, V
Parameter
Pulse Width Variation
Average Pulse Width Distortion t
Pulse Width Variation
Average Pulse Width Distortion t
I
=0.0V or V
[1]
I
ext
=5.0V)
is 15K. With R
PWV
) and Average Pulse Width Distortion (t
Symbol
t
t
PWV
APWD
PWV
APWD
ext
[2]
=30K the optical output power is about –3dB of the nominal value. Typical behaviour see Fiure below.
Symbol
V
V
I
C
R
I
I
L
CC
LP2
IL
IH
I
I
Electrical Input Signal Optical Output Signal
Min
22.9
1.0
21.1
-0.5
PWV
Max
24.1
1.5
23.1
0.5
and t
Min
-0.3
2.0
-
-
100
-
-
PWV
PWV
apwd
and t
and t
Typ
-
-
-
-
-
25
-
Mix
20.9
-0.5
19.1
-2.0
APWD
at SP1, then the output signal SP2 is systematically
APWD
apwd
)
at SP1 have to be longer than described in the
do not meet the MOST Specification of Physical
Max
24.4
1.5
23.4
0.5
Max
0.8
V
+/- 20
7
-
35
1
CC
+ 0.3
Unit
V
V
µA
pF
kOhm
mA
mA
Unit
ns
ns
ns
ns
Remarks
Optical Output Signal according to
MOST Specification of Physical Layer
Rev. 1.0
Electrical Input Signal according to
MOST Specification of Physical Layer
Rev. 1.0
ext
. The