TC9400CPD TELCOM SEMICONDUCTOR, TC9400CPD Datasheet - Page 10

• Manufacturer Part Number: TC9400CPD
• Description: IC, F/V-V/F CONVERTER, 9400, DIP14
• Manufacturer: TELCOM SEMICONDUCTOR

Specifications of TC9400CPD

• Frequency: 100kHz
• Linearity %: 0.05%
• Supply Voltage Range: ± 4V To ± 7.5V
• Digital Ic Case Style: DIP
• No. Of Pins: 14
• Operating Temperature Max: 70°C
• Operating Temperature Min: 0°C
• Package /: RoHS Compliant
• Full Scale Range: 10Hz To 100kHz
• Rohs Compliant: Yes
• Bandwidth: 100kHz
• Base Number: 9400

TC9400/9401/9402
5.0
5.1
The output frequency (F
input voltage (V
EQUATION 5-1:
5.2
5.2.1
The value of this component is chosen to give a full
scale input current of approximately 10µA:
EQUATION 5-2:
EQUATION 5-3:
Note that the value is an approximation and the exact
relationship is defined by the transfer equation. In prac-
tice, the value of R
obtain full scale frequency at V
Section 5.3, Adjustment Procedure). Metal film resis-
tors with 1% tolerance or better are recommended for
high accuracy applications because of their thermal
stability and low noise generation.
5.2.2
The exact value is not critical but is related to C
the relationship:
Improved stability and linearity are obtained when
C
although mica and ceramic devices can be used in
applications where their temperature limits are not
exceeded. Locate as close as possible to Pins 12
and 13.
5.2.3
The exact value is not critical and may be used to trim
the full scale frequency (see Section 7.1, Input/Output
Relationships). Glass film or air trimmer capacitors are
recommended because of their stability and low leak-
age. Locate as close as possible to Pins 5 and 3 (see
Figure 5-1).
DS21483B-page 10
INT
≤ 4C
Frequency Out =
VOLTAGE-TO-FREQUENCY
(V/F) CONVERTER DESIGN
INFORMATION
Input/Output Relationships
External Component Selection
REF
R
C
C
. Low leakage types are recommended,
IN
INT
REF
3C
IN
R
IN
) by the transfer equation:
R
REF
IN
≅
IN
≅
V
≤ C
typically would be trimmed to
IN
10µA
10V
OUT
R
V
INT
FULLSCALE
IN
IN
10µA
) is related to the analog
≤ 10C
, x
= 1MΩ
(V
REF
IN
REF
full scale (see
)(V
1
REF
)
REF
by
FIGURE 5-1:
5.2.4
Power supplies of ±5V are recommended. For high
accuracy requirements, 0.05% line and load regulation
and 0.1µF disc decoupling capacitors, located near the
pins, are recommended.
5.3
Figure 3-1 shows a circuit for trimming the zero loca-
tion. Full scale may be trimmed by adjusting R
or C
scale frequency is as follows:
1.
2.
If adjustments are performed in this order, there should
be no interaction and they should not have to be
repeated.
5.4
A TC9400, which operates from a single 12 to 15V vari-
able power source, is shown in Figure 5-2. This circuit
uses two Zener diodes to set stable biasing levels for
the TC9400. The Zener diodes also provide the refer-
ence voltage, so the output impedance and tempera-
ture coefficient of the Zeners will directly affect power
supply rejection and temperature performance. Full
scale adjustment is accomplished by trimming the input
current. Trimming the reference voltage is not recom-
mended for high accuracy applications unless an
Op Amp is used as a buffer, because the TC9400
requires a low impedance reference (see Section 4.9,
V
The circuit of Figure 5-2 will directly interface with
CMOS logic operating at 12V to 15V. TTL or 5V CMOS
logic can be accommodated by connecting the output
pull-up resistors to the +5V supply. An optoisolator can
also be used if an isolated output is required; also, see
Figure 5-3.
REF
Set V
to obtain a 10Hz output frequency.
Set V
to obtain a 10kHz output frequency.
REF
pin description, for more information).
. Recommended procedure for a 10kHz full
Adjustment Procedure
Improved Single Supply V/F
Converter Operation
500
400
300
200
100
IN
IN
V
0
to 10V and trim either R
to 10mV and trim the zero adjust circuit
DD
, V
-1
SS
-2
C
RECOMMENDED
10kHz
©
REF
2002 Microchip Technology Inc.
V
-3
100kHz
REF
VS. V
-4
(V)
REF
IN
V
V
R
V
T
-5
A
DD
SS
IN
IN
, V
= +25°C
= +10V
= 1MΩ
REF
= -5V
= +5V
-6
, or C
-7
IN
, V
REF
REF
,