SEMICONDUCTOR
8-153
November 1996
ICL8038
Precision Waveform Generator/
Voltage Controlled Oscillator
Features
• Low Frequency Drift with Temperature . . . 250ppm/oC
• Low Distortion . . . . . . . . . . . . . 1% (Sine Wave Output)
• High Linearity . . . . . . . . .0.1% (Triangle Wave Output)
• Wide Frequency Range. . . . . . . . . . 0.001Hz to 300kHz
• Variable Duty Cycle . . . . . . . . . . . . . . . . . . . . 2% to 98%
• High Level Outputs . . . . . . . . . . . . . . . . . . . .TTL to 28V
• Simultaneous Sine, Square, and Triangle Wave
Outputs
• Easy to Use - Just a Handful of External Components
Required
Description
The ICL8038 waveform generator is a monolithic integrated
circuit capable of producing high accuracy sine, square, tri-
angular, sawtooth and pulse waveforms with a minimum of
exter nal components. The frequency (or repetition rate) can
be selected externally from 0.001Hz to more than 300kHz
using either resistors or capacitors, and frequency modula-
tion and sweeping can be accomplished with an external
voltage. The ICL8038 is fabricated with advanced monolithic
technology, using Schottky barrier diodes and thin film resis-
tors, and the output is stable over a wide range of tempera-
ture and supply variations. These devices may be interfaced
with phase locked loop circuitry to reduce temperature drift
to less than 250ppm/oC.
Ordering Information
PART NUMBER STABILITY TEMP. RANGE (oC) PACKAGE PKG. NO.
ICL8038CCPD 250ppm/oC (Typ) 0 to 70 14 Ld PDIP E14.3
ICL8038CCJD 250ppm/oC (Typ) 0 to 70 14 Ld CERDIP F14.3
ICL8038BCJD 180ppm/oC (Typ) 0 to 70 14 Ld CERDIP F14.3
ICL8038ACJD 120ppm/oC (Typ) 0 to 70 14 Ld CERDIP F14.3
ICL8038BMJD (Note) 350ppm/oC (Max) -55 to 125 14 Ld CERDIP F14.3
ICL8038AMJD (Note) 250ppm/oC (Max) -55 to 125 14 Ld CERDIP F14.3
NOTE: Add /883B to part number if 883 processing is required.
Pinout
ICL8038
(PDIP, CERDIP)
TOP VIEW
Functional Diagram
SINE
TRIANGLE
DUTY CYCLE
V+
FM BIAS
NC
NC
SINE WAVE
V- OR GND
TIMING
SQUARE
FM SWEEP
1
2
3
4
5
6
7
14
13
12
11
10
9
8
ADJUST
CAPACITOR
WAVE OUT
INPUT
SINE WAVE
ADJUST
WAVE OUT
OUT
FREQUENCY
ADJUST
COMPARATOR
#1
COMPARATOR
#2
FLIP-FLOP
SINE
CONVERTER
BUFFERBUFFER
92
11
I10
6V+
V- OR GND
CURRENT
SOURCE
#1
CURRENT
SOURCE
#2
2I C
3
CAUTION: These devices are sensitive to electrostatic discharge. Users should follow proper IC Handling Procedures.
Copyright © Harris Corporation 1996 File Number 2864.2
8-154
Absolute Maximum Ratings Thermal Information
Supply Voltage (V- to V+) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36V
Input Voltage (Any Pin). . . . . . . . . . . . . . . . . . . . . . . . . . . . . V- to V+
Input Current (Pins 4 and 5). . . . . . . . . . . . . . . . . . . . . . . . . . .25mA
Output Sink Current (Pins 3 and 9) . . . . . . . . . . . . . . . . . . . . .25mA
Operating Conditions
Temperature Range
ICL8038AM, ICL8038BM . . . . . . . . . . . . . . . . . . . -55oC to 125oC
ICL8038AC, ICL8038BC, ICL8038CC . . . . . . . . . . . .0oC to 70oC
Thermal Resistance (Typical, Note 1) θJA (oC/W) θJC (oC/W)
CERDIP Package . . . . . . . . . . . . . . . . 75 20
PDIP Package . . . . . . . . . . . . . . . . . . . 115 N/A
Maximum J unction Temperature (Cer amic Package) . . . . . . . . 175oC
Maximum Junction Temperature (Plastic Package) . . . . . . . . 150oC
Maximum Storage Temperature Range . . . . . . . . . .-65oC to 150oC
Maximum Lead Temperature (Soldering 10s). . . . . . . . . . . . . 300oC
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation
of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
NOTE:
1. θJA is measured with the component mounted on an evaluation PC board in free air.
Electrical Specifications VSUPPLY = ±10V or +20V, TA = 25oC, RL = 10kΩ, Test Circuit Unless Otherwise Specified
PARAMETER SYMBOL TEST
CONDITIONS
ICL8038CC ICL8038BC(BM) ICL8038AC(AM)
UNITSMIN TYP MAX MIN TYP MAX MIN TYP MAX
Supply Voltage Operating Range VSUPPLY
V+ Single Supply +10 - +30 +10 - +30 +10 - +30 V
V+, V- Dual Supplies ±5-±15 ±5-±15 ±5-±5V
Supply Current ISUPPLY VSUPPLY = ±10V
(Note 2)
8038AM 8038BM - - - 12 15 - 12 15 mA
8038AC, 8038BC, 8038CC 12 20 - 12 20 - 12 20 mA
FREQUENCY CHARACTERISTICS (All Waveforms)
Max. Frequency of Oscillation fMAX 100 - - 100 - - 100 - - kHz
Sweep Frequency of FM Input fSWEEP -10- -10- -10- kHz
Sweep FM Range (Note 3) - 35:1 - - 35:1 - - 35:1 -
FM Linearity 10:1 Ratio - 0.5 - - 0.2 - - 0.2 - %
Frequency Drift with
Temperature (Note 5) ∆f/∆T
8038AC, 8038BC, 8038CC 0oC to 70oC - 250 - - 180 - - 120 ppm/oC
8038AM, 8038BM -55oC to 125oC - - - - 350 - - 250 ppm/oC
Frequency Drift with Supply Volt-
age ∆f/∆V Over Supply
Voltage Range - 0.05 - - 0.05 - 0.05 - %/V
OUTPUT CHARACTERISTICS
Square Wave -
Leakage Current IOLK V9 = 30V - - 1 - - 1 - - 1 µA
Saturation Voltage VSAT ISINK = 2mA - 0.2 0.5 - 0.2 0.4 - 0.2 0.4 V
Rise Time tRRL = 4.7kΩ- 180 - - 180 - - 180 - ns
Fall Time tFRL = 4.7kΩ-40- -40- -40- ns
Typical Duty Cycle Adjust
(Note 6) ∆D 2 98 2 - 98 2 - 98 %
Triangle/Sawtooth/Ramp -
Amplitude VTRIAN-
GLE RTRI = 100kΩ0.30 0.33 - 0.30 0.33 - 0.30 0.33 - xVSUPPLY
Linearity - 0.1 - - 0.05 - - 0.05 - %
ICL8038
8-155
Output Impedance ZOUT IOUT = 5mA - 200 - - 200 - - 200 - Ω
Sine Wave
Amplitude VSINE RSINE = 100kΩ0.2 0.22 - 0.2 0.22 - 0.2 0.22 - xVSUPPLY
THD THD RS = 1MΩ
(Note 4) - 2.0 5 - 1.5 3 - 1.0 1.5 %
THD Adjusted THD Use Figure 4 - 1.5 - - 1.0 - - 0.8 - %
NOTES:
2. RA and RB currents not included.
3. VSUPPLY = 20V; RA and RB = 10kΩ, f ≅ 10kHz nominal; can be extended 1000 to 1. See Figures 5A and 5B.
4. 82kΩ connected between pins 11 and 12, Triangle Duty Cycle set at 50%. (Use RA and RB.)
5. Figure 1, pins 7 and 8 connected, VSUPPLY = ±10V. See Typical Curves for T.C. vs VSUPPLY.
6. Not tested, typical value for design purposes only.
Electrical Specifications VSUPPLY = ±10V or +20V, TA = 25oC, RL = 10kΩ, Test Circuit Unless Otherwise Specified (Continued)
PARAMETER SYMBOL TEST
CONDITIONS
ICL8038CC ICL8038BC(BM) ICL8038AC(AM)
UNITSMIN TYP MAX MIN TYP MAX MIN TYP MAX
Test Conditions
PARAMETER RARBRLCSW
1MEASURE
Supply Current 10kΩ10kΩ10kΩ3.3nF Closed Current Into Pin 6
Sweep FM Range (Note 7) 10kΩ10kΩ10kΩ3.3nF Open Frequency at Pin 9
Frequency Drift with Temperature 10kΩ10kΩ10kΩ3.3nF Closed Frequency at Pin 3
Frequency Drift with Supply Voltage (Note 8) 10kΩ10kΩ10kΩ3.3nF Closed Frequency at Pin 9
Output Amplitude (Note 10)
Sine 10kΩ10kΩ10kΩ3.3nF Closed Pk-Pk Output at Pin 2
Triangle 10kΩ10kΩ10kΩ3.3nF Closed Pk-Pk Output at Pin 3
Leakage Current (Off) (Note 9) 10kΩ10kΩ3.3nF Closed Current into Pin 9
Saturation Voltage (On) (Note 9) 10kΩ10kΩ3.3nF Closed Output (Low) at Pin 9
Rise and Fall Times (Note 11) 10kΩ10kΩ4.7kΩ3.3nF Closed Waveform at Pin 9
Duty Cycle Adjust (Note 11)
Max 50kΩ~1.6kΩ10kΩ3.3nF Closed Waveform at Pin 9
Min ~25kΩ50kΩ10kΩ3.3nF Closed Waveform at Pin 9
Triangle Waveform Linearity 10kΩ10kΩ10kΩ3.3nF Closed Waveform at Pin 3
Total Harmonic Distortion 10kΩ10kΩ10kΩ3.3nF Closed Waveform at Pin 2
NOTES:
7. The hi and lo frequencies can be obtained by connecting pin 8 to pin 7 (fHI) and then connecting pin 8 to pin 6 (fLO). Otherwise apply
Sweep Voltage at pin 8 (2/3 VSUPPLY +2V) ≤ VSWEEP ≤ VSUPPLY where VSUPPLY is the total supply voltage. In Figure 5B, pin 8 should
vary between 5.3V and 10V with respect to ground.
8. 10V ≤ V+ ≤ 30V, or ±5V ≤ VSUPPLY ≤±15V.
9. Oscillation can be halted by forcing pin 10 to +5V or -5V.
10. Output Amplitude is tested under static conditions by forcing pin 10 to 5V then to -5V.
11. Not tested; for design purposes only.
ICL8038
8-156
Test Circuit
Application Information
(See Functional Diagram)
An exter nal capacitor C is charged and discharged by two cur-
rent sources. Current source #2 is s witched on and off by a flip-
flop, while current source #1 is on continuously. Assuming that
the flip-flop is in a state such that current source #2 is off, and
the capacitor is charged with a current I, the voltage across the
capacitor rises linearly with time. When this voltage reaches the
le v el of comparator #1 (set at 2/3 of the supply v oltage), the flip-
flop is triggered, changes states, and releases current source
#2. This current source normally carries a current 2I, thus the
capacitor is discharged with a net-current I and the voltage
across it drops linearly with time. When it has reached the le vel
of comparator #2 (set at 1/3 of the supply voltage), the flip-flop
is triggered into its original state and the cycle starts again.
F our w a veforms are readily obtainable from this basic gener-
ator circuit. With the current sources set at I and 2I respec-
tively, the charge and discharge times are equal. Thus a
triangle waveform is created across the capacitor and the
flip-flop produces a square wave. Both waveforms are fed to
buffer stages and are available at pins 3 and 9.
Detailed Schematic
ICL8038
456
9
2
121110
8
7
SW1
N.C.
C
3300pF 82K
RA
10K RB
10K RL
10K
RTRI
RSINE
-10V
3
+10V
FIGURE 1. TEST CIRCUIT
Q20Q21
Q19 Q22
Q31
Q32
Q33
Q34
Q30
Q7
Q6
Q1
Q2
Q4
Q8Q9
Q5
Q3
Q14
Q11 Q12 Q13
Q24
Q23
Q25
Q26
Q29
Q27
Q28
Q10
Q15 Q18
Q17
Q16
Q35
Q36 Q38 Q40
Q37 Q39
R1
11K
R2
39K
7
854
REXT BR
EXT A
COMPARATOR
R41
4K
R8
5K
R9
5K
R10
5K
R43
27K
R42
27K BUFFER AMPLIFIER
R41
27K
R17
4.7K
R18
4.7K
R14
27K
R13
620 R16
1.8K
R6
100
R5
100
R4
100
R3
30K
R46
40K CEXT
R7A
10K
R7B
15K
R44
1K
3
10
R11
270
R12
2.7K R15
470
R24
800
2
R21
10K
R20
2.7K
R19
800
FLIP-FLOP SINE CONVERTER
Q49
Q50
Q52
Q51
Q53
Q55
Q54
Q56
Q42
Q41
Q43
Q44
Q45
Q46
Q47
Q48
6V+
1
12
R32
5.2K
R33
200
R34
375
R35
330
R36
1600
R37
330
R38
375
R39
200
R40
5.6K REXTC
82K
R23
2.7K
R22
10K
R28
33K R30
33K
R29
33K R31
33K
R25
33K R26
33K R27
33K R45
33K
CURRENT SOURCES
9
11
ICL8038
8-157
The levels of the current sources can, however, be selected
ov er a wide r ange with two external resistors. Theref ore , with
the two currents set at values different from I and 2I, an
asymmetrical sawtooth appears at Terminal 3 and pulses
with a duty cycle from less than 1% to greater than 99% are
available at Terminal 9.
The sine wave is created by feeding the triangle wave into a
nonlinear network (sine conver ter). This network provides a
decreasing shunt impedance as the potential of the triangle
moves toward the two extremes.
Waveform Timing
The
symmetry
of all waveforms can be adjusted with the
external timing resistors. Two possible ways to accomplish
this are shown in Figure 3. Best results are obtained by
keeping the timing resistors RA and RB separate (A). RA
controls the rising por tion of the triangle and sine wave and
the 1 state of the square wave.
The magnitude of the triangle waveform is set at 1/3
VSUPPLY; therefore the rising portion of the triangle is,
The falling portion of the triangle and sine wave and the 0
state of the square wave is:
Thus a 50% duty cycle is achieved when RA = RB.
If the duty cycle is to be varied ov er a small r ange about 50%
only, the connection shown in Figure 3B is slightly more con-
venient. A 1k Ω potentiometer may not allow the duty cycle to
be adjusted through 50% on all devices. If a 50% duty cycle
is required, a 2kΩ or 5kΩ potentiometer should be used.
With two separate timing resistors , the frequency is giv en by:
or, if RA = RB = R
Neither time nor frequency are dependent on supply voltage ,
even though none of the voltages are regulated inside the
integrated circuit. This is due to the fact that both currents
and thresholds are direct, linear functions of the supply volt-
age and thus their effects cancel.
t1CV×
I
-------------- C 1/3 VSUPPLY RA
××× 0.22 VSUPPLY
×
------------------------------------------------------------------- RAC×
0.66
------------------== =
t
2
CV
×
1
------------- C 1/3VSUPPLY
×
2 0.22()
V
SUPPLY
RB
------------------------ 0.22VSUPPLY
RA
------------------------
–
----------------------------------------------------------------------------------- RARBC
0.66 2RARB
–()
--------------------------------------== =
f
1
t
1
t
2
+
---------------- 1
RAC
0.66
------------ 1RB
2RARB
–
-------------------------+
------------------------------------------------------==
f
0.33
RC
----------- (for Figure 3A)=
FIGURE 2A. SQUARE WAVE DUTY CYCLE - 50% FIGURE 2B. SQUARE WAVE DUTY CYCLE - 80%
FIGURE 2. PHASE RELATIONSHIP OF WAVEFORMS
FIGURE 3A. FIGURE 3B.
FIGURE 3. POSSIBLE CONNECTIONS FOR THE EXTERNAL TIMING RESISTORS
C 82K
ICL8038
456
9
2
121110
8
7
RARL
V- OR GND
3
RB
V+
ICL8038
456
9
2
121110
8
7
C 100K
RARL
V- OR GND
3
RB
V+
1kΩ
ICL8038
8-158
Reducing Distortion
To minimize sine wave distortion the 82kΩ resistor between
pins 11 and 12 is best made variable. With this arrangement
distor tion of less than 1% is achievable. To reduce this even
further, two potentiometers can be connected as shown in
Figure 4; this configuration allows a typical reduction of sine
wave distortion close to 0.5%.
Selecting RA, RB and C
For any given output frequency, there is a wide range of RC
combinations that will work, however cer tain constraints are
placed upon the magnitude of the charging current for opti-
mum performance. At the low end, currents of less than 1µA
are undesirable because circuit leakages will contribute sig-
nificant errors at high temperatures. At higher currents
(I > 5mA), transistor betas and saturation voltages will con-
tribute increasingly larger errors. Optimum performance will,
therefore, be obtained with charging currents of 10µA to
1mA. If pins 7 and 8 are shor ted together, the magnitude of
the charging current due to RA can be calculated from:
R1 and R2 are shown in the Detailed Schematic.
A similar calculation holds for RB.
The capacitor value should be chosen at the upper end of its
possible range.
Waveform Out Level Control and Power Supplies
The waveform generator can be operated either from a sin-
gle power supply (10V to 30V) or a dual power supply (±5V
to ±15V). With a single power supply the average levels of
the triangle and sine wave are at exactly one-half of the sup-
ply voltage, while the square wave alternates between V+
and ground. A split power supply has the advantage that all
waveforms move symmetrically about ground.
The square wave output is not committed. A load resistor
can be connected to a different power supply, as long as the
applied voltage remains within the breakdown capability of
the waveform generator (30V). In this way, the square wave
output can be made TTL compatible (load resistor con-
nected to +5V) while the waveform generator itself is pow-
ered from a much higher voltage.
Frequency Modulation and Sweeping
The frequency of the waveform generator is a direct function
of the DC voltage at Terminal 8 (measured from V+). By
altering this voltage, frequency modulation is performed. For
small deviations (e.g. ±10%) the modulating signal can be
applied directly to pin 8, merely providing DC decoupling
with a capacitor as shown in Figure 5A. An external resistor
between pins 7 and 8 is not necessary, but it can be used to
increase input impedance from about 8kΩ (pins 7 and 8 con-
nected together), to about (R + 8kΩ).
For larger FM deviations or for frequency sweeping, the
modulating signal is applied between the positive supply
voltage and pin 8 (Figure 5B). In this way the entire bias for
the current sources is created by the modulating signal, and
a very large (e.g. 1000:1) sweep range is created (f = 0 at
VSWEEP = 0). Care must be taken, however, to regulate the
supply voltage; in this configuration the charge current is no
longer a function of the supply v oltage (yet the trigger thresh-
olds still are) and thus the frequency becomes dependent on
the supply voltage. The potential on Pin 8 may be swept
down from V+ by (1/3 VSUPPLY - 2V).
ICL8038
456
9
2
121110
8
7
C100kΩ
RARL
V- OR GND
3
RB
V+
1kΩ
110kΩ100kΩ
10kΩ
FIGURE 4. CONNECTION TO ACHIEVE MINIMUM SINE WAVE
DISTORTION
IR1V+ V-–()×
R
1
R
2
+()
---------------------------------------- 1
RA
--------
×0.22 V+ V-–()
R
A
------------------------------------==
C 81K
ICL8038
456
9
2
121110
8
7
RARL
V- OR GND
3
RB
V+
R
FM
FIGURE 5A. CONNECTIONS FOR FREQUENCY MODULATION
C 81K
ICL8038
456
9
2
121110
8
RARL
V- OR GND
3
RB
V+
SWEEP
VOLTAGE
FIGURE 5B. CONNECTIONS FOR FREQUENCY SWEEP
FIGURE 5.
ICL8038
8-159
Typical Applications
The sine wa ve output has a relatively high output impedance
(1kΩ Typ). The circuit of Figure 6 provides buffering, gain
and amplitude adjustment. A simple op amp follower could
also be used.
With a dual supply voltage the external capacitor on Pin 10 can
be shorted to ground to halt the ICL8038 oscillation. Figure 7
shows a FET switch, diode ANDed with an input strobe signal
to allow the output to alw a ys start on the same slope.
To obtain a 1000:1 Sweep Range on the ICL8038 the volt-
age across external resistors RA and RB must decrease to
nearly zero. This requires that the highest voltage on control
Pin 8 exceed the voltage at the top of RA and RB by a few
hundred mV. The Circuit of Figure 8 achieves this by using a
diode to lower the effective supply voltage on the ICL8038.
The large resistor on pin 5 helps reduce duty cycle variations
with sweep.
The linearity of input sweep voltage versus output frequency
can be significantly improved by using an op amp as shown
in Figure 9.
C
ICL8038
456
2
1110
8
7
RA
100K
V-
RB
V+
AMPLITUDE
20K
+
-
741
4.7K
FIGURE 6. SINE WAVE OUTPUT BUFFER AMPLIFIERS
C
ICL8038
45 9
1011
8
7
RA
1N914
-15V
RB
V+
STROBE
2
2N4392 1N914
15K
100K
OFF
ON
+15V (+10V)
-15V (-10V)
FIGURE 7. STROBE TONE BURST GENERATOR
0.0047µFDISTORTION
ICL8038
546
9
2
121110
8
4.7K
-10V
3
+10V
20K
4.7K
1K
DUTY CYCLE
15K
1N457
0.1µF
100K
≈15M
10K
FREQ.
I
GURE 8. VARIABLE AUDIO OSCILLATOR, 20Hz TO 20kHzY
ICL8038
8-160
Use in Phase Locked Loops
Its high frequency stability makes the ICL8038 an ideal
building b loc k for a phase loc k ed loop as shown in Figure 10.
In this application the remaining functional blocks, the phase
detector and the amplifier, can be formed by a number of
available ICs (e.g., MC4344, NE562, HA2800, HA2820).
In order to match these building blocks to each other, two
steps must be taken. First, two different supply voltages are
used and the square wa ve output is returned to the supply of
the phase detector. This assures that the VCO input voltage
will not exceed the capabilities of the phase detector. If a
smaller VCO signal is required, a simple resistive voltage
divider is connected between pin 9 of the waveform genera-
tor and the VCO input of the phase detector.
Second, the DC output level of the amplifier must be made
compatible to the DC level required at the FM input of the
wa v e f orm generator (pin 8, 0.8V+). The simplest solution here
is to provide a voltage divider to V+ (R1, R2 as shown) if the
amplifier has a lower output level, or to ground if its level is
higher. The divider can be made part of the low-pass filter.
This application not only provides for a free-running fre-
quency with very low temperature drift, but is also has the
unique feature of producing a large reconstituted sinewave
signal with a frequency identical to that at the input.
For fur ther information, see Harris Application Note AN013,
“Everything You Always Wanted to Know About the
ICL8038”.
SINE WAVE
ICL8038
45
6
3
1
121110
8
7
R1
V-/GND
2
DUTY V2+
CYCLE
FREQUENCY
ADJUST
ADJ.
9
SINE WAVE
TRIANGLE
OUT
SINE WAVE
ADJ.
TIMING
CAP.
FM BIAS
SQUARE
WAVE
OUT
R2
LOW PASS
FILTER
DEMODULATED
FM
AMPLIFIER
PHASE
DETECTOR
VCO
IN
INPUT
V1+
OUT
FIGURE 9. WAVEFORM GENERATOR USED AS STABLE VCO IN A PHASE-LOCKED LOOP
3,900pF SINE WAVE
ICL8038
456
9
2
121110
8
4.7kΩ
3
4.7kΩ
500Ω10kΩ
1N753A
DISTORTION
FUNCTION GENERATOR
100kΩ
+
50µF
15V
1MΩ
(6.2V)
HIGH FREQUENCY
SYMMETRY
100kΩ
LOW FREQUENCY
SYMMETRY
100kΩ
+
-741
+15V
-15V
SINE WAVE
OUTPUT
+
-741
+15V
1kΩ
10kΩ
OFFSET
-VIN P4
1,000pF
1kΩ
FIGURE 10. LINEAR VOLTAGE CONTROLLED OSCILLATOR
ICL8038
8-161
Definition of Terms
Supply Voltage (VSUPPLY). The total supply voltage from
V+ to V-.
Supply Current. The supply current required from the
power supply to operate the device, excluding load currents
and the currents through RA and RB.
Frequency Range. The frequency range at the square wav e
output through which circuit operation is guaranteed.
Sweep FM Range. The ratio of maximum frequency to mini-
mum frequency which can be obtained by applying a sweep
voltage to pin 8. For correct operation, the sweep voltage
should be within the range:
(2/3 VSUPPLY + 2V) < VSWEEP < VSUPPLY
FM Linearity. The percentage deviation from the best fit
straight line on the control voltage versus output frequency
curve.
Output Amplitude. The peak-to-peak signal amplitude
appearing at the outputs.
Saturation Voltage. The output voltage at the collector of
Q23 when this transistor is turned on. It is measured for a
sink current of 2mA.
Rise and Fall Times. The time required for the square wave
output to change from 10% to 90%, or 90% to 10%, of its
final value.
Triangle Waveform Linearity. The percentage deviation
from the best fit straight line on the rising and falling triangle
waveform.
Total Harmonic Distortion. The total harmonic distortion at
the sine wave output.
Typical Performance Curves
FIGURE 11. SUPPLY CURRENT vs SUPPLY VOLTAGE FIGURE 12. FREQUENCY vs SUPPLY VOLTAGE
FIGURE 13. FREQUENCY vs TEMPERATURE FIGURE 14. SQUARE WAVE OUTPUT RISE/FALL TIME vs
LOAD RESISTANCE
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
5 1015202530
5
10
15
20
25oC
125oC
-55oC
SUPPLY VOLTAGE (V)
NORMALIZED FREQUENCY
51015202530
0.98
0.99
1.01
1.03
1.00
1.02
TEMPERATURE (oC)
NORMALIZED FREQUENCY
-50 -25 0 25 75 125
0.98
0.99
1.01
1.03
1.00
1.02
30
20
10
20
30
10
LOAD RESISTANCE (kΩ)
1064208
0
50
100
150
200
TIME (ns)
125oC
FALL TIME
RISE TIME
25oC
-55oC125oC
25oC
-55oC
ICL8038
8-162
FIGURE 15. SQUARE WAVE SATURATION VOLTAGE vs LOAD
CURRENT FIGURE 16. TRIANGLE WAVE OUTPUT VOLTAGE vs LOAD
CURRENT
FIGURE 17. TRIANGLE WAVE OUTPUT VOLTAGE vs
FREQUENCY FIGURE 18. TRIANGLE WAVE LINEARITY vs FREQUENCY
FIGURE 19. SINE WAVE OUTPUT VOLTAGE vs FREQUENCY FIGURE 20. SINE WAVE DISTORTION vs FREQUENCY
Typical Performance Curves
(Continued)
LOAD CURRENT (mA)
SATURATION VOLTAGE
1064208
2
1.5
1.0
0.5
0
125oC
25oC
-55oC
LOAD CURRENT (mA)
NORMALIZED PEAK OUTPUT VOLTAGE
16642010201814128
0.8
0.9
1.0
LOAD CURRENT
LOAD CURRENT TO V+
25oC
125oC
-55oC
TO V-
FREQUENCY (Hz)
10K1K10010 1M100K
0.6
0.7
0.8
0.9
1.0
1.1
1.2
NORMALIZED OUTPUT VOLTAGE
FREQUENCY (Hz)
10K1K10010 1M100K
0.01
0.1
1.0
10.0
LINEARITY (%)
FREQUENCY (Hz)
10K1K10010 1M100K
0.9
1.0
1.1
NORMALIZED OUTPUT VOLTAGE
ADJUSTED
FREQUENCY (Hz)
10K
1K
10010 1M100K
2
4
6
DISTORTION (%)
0
8
10
12
UNADJUSTED
ICL8038