TIL300 Datasheet, PDF (1/6 Pages) List of Unclassifed Manufacturers – PRECISION LINEAR OPTOCOUPLER

TIL300, TIL300A
PRECISION LINEAR OPTOCOUPLER
D ac or dc Signal Coupling
D Wide Bandwidth . . . >ā 200 kHz
D High Transfer-Gain Stability . . . ±0.05%/°C
D 3500 V Peak Isolation
D UL Approval Pending
D Applications
− Power-Supply Feedback
− Medical-Sensor Isolation
− Opto Direct-Access Arrangement (DAA)
− Isolated Process-Control Transducers
SOES019A − OCTOBER 1995 − REVISED JULY 1996
P PACKAGE
(TOP VIEW)
LEDK 1
LEDA 2
PDK1 3
PDA1 4
8 NC
7 NC
6 PDK2
5 PDA2
NC − No internal connection
description
The TIL300 precision linear optocoupler consists of an infrared LED irradiating an isolated feedback photodiode
and an output photodiode in a bifurcated arrangement. The feedback photodiode captures a percentage of the
flux of the LED and generates a control signal that can be used to regulate the LED drive current. This technique
is used to compensate for the nonlinear time and temperature characteristics of the LED. The output-side
photodiode produces an output signal that is linearly proportional to the servo-optical flux emitted from the LED.
A typical application circuit (shown in Figure 1) uses an operational amplifier as the input to drive the LED. The
feedback photodiode sources current through R1, which is connected to the inverting input of the input
operational amplifier. The photocurrent I_P1 assumes a magnitude that satisfies the relationship I_P1 = V_I/R1. The
magnitude of the current is directly proportional to the LED current through the feedback transfer gain
K1(V_I/R1 = K1 × I_F). The operational amplifier supplies LED current to produce sufficient photocurrent to keep
the node voltage V_b equal to node voltage V_a.
TIL300
1
+
VI
−
R1
1VCC+
Va
+
Vb _{_}
1VCC−
P
R3
2
IF
3
1VCC+
4
K2
K1
6 _2VCC+
5
2VCC+
−
+
VO = K3(R2 / R1) VI
P
IP1
IP2
R2 _2VCC−
NOTES: A. K1 is servo current gain, the ratio of the feedback photodiode current (IP1) to the input LED current (IF), i.e. K1 = IP1/IF.
B. K2 is forward gain, the ratio of the output photodiode current (IP2) to the input LED current (IF), i.e. K2 = IP2/IF.
C. K3 is transfer gain, the ratio of the forward gain to the servo gain, i.e. K3 = K2/K1.
Figure 1. Typical Application Circuit
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright  1996, Texas Instruments Incorporated
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• POST OFFICE BOX 1443 HOUSTON, TEXAS 77251−1443
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