![](http://datasheet.mmic.net.cn/390000/HIP2030_datasheet_16810689/HIP2030_9.png)
9
FIGURE 9. PROPAGATION DELAY vs VOLTAGE OVERDRIVE
FOR A, B1, AND B2 CHANNELS
Appendix A Exercises
FIGURE 10. PROPAGATION DELAY vs VOLTAGE OVERDRIVE
FOR G CHANNEL
The maximum value of R1 can easily be determined in four
design steps:
Typical Performance Curves
(Continued)
0.01
0.02 0.03
0.05
0.1
0.2
0.3
0.5
1.0
50
100
200
300
500
OVERDRIVE VOLTAGE (V)
P
+150
o
C
+100
o
C
+25
o
C
0
o
C
-40
o
C
0.01
0.02 0.03
0.05
0.1
0.2
0.3
0.5
1.0
50
100
200
300
500
OVERDRIVE VOLTAGE (V)
P
+150
o
C
+100
o
C
+25
o
C
0
o
C
-40
o
C
0.01
=
0.02 0.03
0.05
0.1
0.2
0.3
0.5
1.0
50
100
200
300
500
OVERDRIVE VOLTAGE (V)
P
+150
C
+100
o
C
+25
o
C
0
o
C
o
C
IVDR
140
160
180
200
+50
+75
+100
T
o
C
2. Select a usable value of V
P0
between 7V and 15V DC.
FREQUENCY (kHz)
5.45K
HIP2030
Exercise 1.1
Q:
How do I calculate the value of the series dropping resis-
tor R1, shown in Figure 3
A:
The values for R1, R
Q
, R
R
and R
VPO
can be determined
by using Equations 1 (A, B, C, and D).
Where:
V
PO
= Voltage between pins P0 and P- (U1 - U22
and U1 - U16).
I
QPO
= Quiescent current flowing into pin P0.
I
QPTO
= Quiescent current of the HBR-2521 fiber-
optic receiver.
I
VDR
= Current flowing through R3 and R4 (volt-
age divider reference).
I
RP
= Current flowing through pull up resistor R2
(in “ON” or “OFF” state)
RQ
IQPO
-------------
=
(EQ. 1A)
RR
IOPTO
IRP
+
+
-----------------------------------------------------
=
(EQ. 1B)
RVPO
RQ
RR
+
-----------1
(EQ. 1C)
1. Assume the following values:
V
IN
= 30V DC
I
QPO
= 2.75mA at V
P0
= 15V
I
OPTO
= 5mA
I
VDR
= 2.5mA
I
RP(ON)
= 5mA, R2 = 1K, VR2 = 5V
Use V
P0
= 15V
3. Solve for R
VP0
using Equations 1 (A, B, and C):
4. Solve for R1 using Equation 1(D):
RQ
------------------
=
=
RR
)
--------------------------------------------------------
1.20K
=
=
RVP0
-------------
-------------
+
----------------------------------
984
=
=
R1
---------------------------------------------
–
(
)
=
(EQ. 1D)
R1
---------------------------------------
)
984
=
=