PIN CONFIGURATIONS FEATURES APPLICATIONS ORDERING INFORMATION BLOCK DIAGRAM. D, N Packages

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1 NE/SE DESCRIPTION The NE/SE Function Generator is a voltage-controlled oscillator of exceptional linearity with buffered square wave and triangle wave outputs. The frequency of oscillation is determined by an external resistor and capacitor and the voltage applied to the control terminal. The oscillator can be programmed over a ten-to-one frequency range by proper selection of an external resistance and modulated over a ten-to-one range by the control voltage, with exceptional linearity. PIN CONFIGURATIONS D, N Packages GROUND 1 NC SQUARE WAVE OUTPUT TRIANGLE WAVE OUTPUT 2 MODULATION INPUT FEATURES Wide range of operating voltage (up to 2V; single or dual) High linearity of modulation Highly stable center frequency (200ppm/ C typical) Highly linear triangle wave output Frequency programming by means of a resistor or capacitor, voltage or current Frequency adjustable over -to-1 range with same capacitor APPLICATIONS Tone generators Frequency shift keying FM modulators Clock generators Signal generators s TOP VIEW ORDERING INFORMATION DESCRIPTION TEMPERATURE RANGE ORDER CODE DWG # -Pin Plastic Small Outline (SO) Package 0 to +0 C NED 01C 1-Pin Ceramic Dual In-Line Package (CERDIP) 0 to +0 C NEF 01B -Pin Plastic Dual In-Line Package (DIP) 0 to +0 C NEN 00B -Pin Plastic Dual In-Line Package (DIP) - C to +12 C SEN 00B BLOCK DIAGRAM MODULATION INPUT CURRENT SOURCES SCHMITT TRIGGER BUFFER AMPLIFIER BUFFER AMPLIFIER April 1,

2 NE/SE EQUIVALENT SCHEMATIC (EXTERNAL) (EXTER NAL) kω 1 GROUND ABSOLUTE MAXIMUM RATINGS SYMBOL PARAMETER RATING UNIT Maximum operating voltage 2 V V IN, Input voltage V P-P T STG Storage temperature range - to + C T A Operating ambient temperature range NE 0 to +0 C SE - to +12 C P D Power dissipation 00 mw April 1,

3 NE/SE DC ELECTRICAL CHARACTERISTICS T A =2 C, C =±V, unless otherwise specified. SYMBOL General PARAMETER SE NE Min Typ Max Min Typ Max T A Operating ambient temperature range C C Operating supply voltage ± ±12 ± ±12 V I CC Operating supply current ma VCO 1 f MAX Maximum operating frequency 1 1 MHz Output UNIT Frequency drift with temperature ppm/ C Frequency drift with supply voltage %/V Control terminal input impedance MΩ FM distortion (±% deviation) % Maximum sweep rate 1 1 MHz Sweep range :1 :1 Triangle wave output impedance 0 0 Ω voltage V P-P linearity % Square wave input impedance 0 0 Ω voltage.. V P-P duty Cycle % t R Rise time ns t F Fall Time 0 0 ns NOTES: 1. The external resistance for frequency adjustment ( ) must have a value between 2kΩ and 20kΩ. 2. The bias voltage ( ) applied to the control terminal (Pin ) should be in the range. April 1,

4 NE/SE TYPICAL PERFORMANCE CHARACTERISTICS NORMALIZED FREQUENCY Normalized Frequency as a Function of Control Voltage RESISTANCE ( ) (K Ω ) Normalized Frequency as a Function of Resistance (R1) = VOLTS CHANGE IN FREQUENCY (%) Change in Frequency as a Function of Temperature Ç +1. = VOLTS +1.0 ÇÇÇ +0. ÇÇÇÇÇÇÇÇ TYPICAL 0 0. ÇÇÇÇ 1.0 ÇÇÇ CONTROL VOLTAGE (BETWEEN PIN AND PIN ) VOLTS NORMALIZED FREQUENCY TEMPERATURE ( o C) SUPPLY CURRENT ma Power Supply Current as a Function of Supply Voltage MAXIMUM TYPICAL R t = kω SUPPLY VOLTAGE V CAPACITANCE 1 (C µ ) F Frequency as a Function of Capacitance (C1) = VOLTS = k 1 2 FREQUENCY Hz OUTPUT V OUTPUT PIN V 12 VCO Output Waveforms OPERATING INSTRUCTIONS The NE/SE Function Generator is a general purpose voltage-controlled oscillator designed for highly linear frequency modulation. The circuit provides simultaneous square wave and triangle wave outputs at frequencies up to 1MHz. A typical connection diagram is shown in Figure 1. The control terminal (Pin ) must be biased externally with a voltage ( ) in the range where C is the total supply voltage. In Figure 1, the control voltage is set by the voltage divider formed with R 2 and R. The modulating signal is then AC coupled with the capacitor C 2. The modulating signal can be direct coupled as well, if the appropriate DC bias voltage is applied to the control terminal. The frequency is given approximately by f O 2 [(V ) ( )] V and should be in the range 2kΩ< <20kΩ. A small capacitor (typically 0.001µF) should be connected between Pins and to eliminate possible oscillation in the control current source. If the VCO is to be used to drive standard logic circuitry, it may be desirable to use a dual supply as shown in Figure 2. In this case the square wave output has the proper DC levels for logic circuitry. RTL can be driven directly from Pin. For DTL or TTL gates, which require a current sink of more than 1mA, it is usually necessary to connect a kω resistor between Pin and negative supply. This increases the current sinking capability to 2mA. The third type of April 1,

5 NE/SE interface shown uses a saturated transistor between the and the logic circuitry. This scheme is used primarily for TTL circuitry which requires a fast fall time (<0ns) and a large current sinking capability. R 2 1.K.001 µ F C 2 R SE/NE 1 V + 1.K.001 µ F SE/NE 1 VOLTS RTL K DTL & T 2 L K DTL OR T 2 L WITH FAST FALL TIME Figure 2. Figure 1. April 1,