Bradley 233 - Technical Description; Timing Section

SECTION 4
TECHNICAL DESCRIPTION
4.1 TIMING SECTION (Printed Circuit Prefix 100. Fig.6)
The functions of the integrated circuits are as follows:
ICIO Input amplifier, Schmitt trigger and Period multivibrator.
IC20 Delay A.
IC30 Width A.
IC40 Delay/Period B
IC50 Width B
IC60 Trigger-light circuit
IC70 Pre-pulse circuit
All the integrated circuits are E. C. L. (emitter-coupled logic) (fig. 1) and the logic levels
(fig. 2) are approximately:
Logic High or 1 -0. 9V
Logic Low or 0 -1. 9V.
These voltage levels do, however, depend on the supply voltage.
The output emitters are open circuit, and therefore normally require a 'pulldown' resistor
to the negative supply of the package.
Inputs have internal 'pulldown' resistors to hold the transistors off when the inputs are not
used.
(For more information on this logic family, read the general section of the Motorola 10, 000
series handbook).
The applications of the E. C. L. gates are:
1. Amplifier
2. Schmitt Trigger
3. Inverter.
4. Non-inverting Buffer.
5. Multivibrator.
6. Mono stable.
7. Differentiator.
8. Catching Diode.
9. Lamp Driver.
10. Transistor Driver.
and the occurrences of these are shown in the table below.
IC
a
b c
d
10 1
2
5
3
20
3,7
7 6
8
30
7
7 6
8
40
7
7 6
8
50
7 7
6
8
60
4
8 6, 9
-
70
4
8
10
10
13