ML2037IP

October 1998 ML2037* 500kHz, Serial Input, Programmable Sine Wave Generator with Digital Gain Control GENERAL DESCRIPTION The ML2037 is a precision programmable sine wave generator with a frequency range of DC to 500kHz. The device is capable of generating a wide frequency range of low distortion sine waves with no external passive components. The frequency of the sine wave output is programmed by a 16-bit word that is loaded through a serial input. The sine wave output frequency is determined by the programmed value and the clock frequency. The clock frequency is derived from either an external crystal connected to the device or an external clock input to provide a stable and accurate frequency reference. The sine wave output of the ML2037 is filtered and has a programmable amplitude that is digitally programmed in 0.5V steps. The maximum amplitude is 2.0VP-P centered at a 2.5V level. The device functions from a single 5V power supply and has a shutdown pin to put the device into a low power mode that disables the output. A sync input is provided to allow the synchronization of more than one device in a system. FEATURES s Programmable output frequency: DC to 400kHz—using a crystal DC to 500kHz—using an external digital clock 3-wire SPI compatible serial interface with double buffered latch for programming the frequency Digital gain control for programming output amplitude SYNC input for synchronization of multiple sine waves Shutdown pin for sleep mode Single 5V power supply operation s s s s s * This Part Is End Of Life As Of August 1, 2000 BLOCK DIAGRAM 11 AVCC 9 AGND REFERENCE DVCC CLK IN 8-BIT DAC CRYSTAL OSCILLATOR 8 PHASE ACCUMULATOR 512 POINT SINE LOOK-UP TABLE 16 16-BIT DATA LATCH S CLK 4 S DATA IN 6 2 SYNC 16-BIT SHIFT REGISTER 16 GAIN CONTROL & SMOOTHING FILTER 12 AVCC SHDN 8 G0 14 G1 15 16 OUT 10 13 D GND 1 5 3 S ENABLE 7 D GND CLK OUT ÷2 1 ML2037 PIN CONFIGURATION ML2037 16-Pin PDIP (P16) 16-Pin Wide SOIC (S16W) D GND 1 SYNC 2 CLK OUT 3 S CLK 4 D GND 5 S DATA IN 6 S ENABLE 7 SHDN 8 16 DVCC 15 G1 14 G0 13 CLK IN 12 AVCC 11 AVCC 10 OUT 9 A GND TOP VIEW PIN DESCRIPTION PIN NAME FUNCTION PIN NAME FUNCTION 1, 5 2 D GND SYNC Ground connection for the digital sections of the IC. Synchronization input. Holding this pin low stops the sine wave output, and resets the phase to zero. Output of the internal high frequency clock generator. fCLK OUT = ½fCLK IN. Serial data clock input. Serial data is clocked into the shift register on falling edges of S CLK. Serial data input for programming the output frequency. 9 10 A GND OUT Ground reference for analog sections of the IC and reference for OUT. Sine wave output. The amplitude of the sine wave will vary around a 2.5V DC level. Power supply for the analog sections of the IC. Input of the internal high frequency clock generator. This pin is either driven from an external clock input or connected to a crystal for use with the internal oscillator. Output gain control. Works with G1 to set the output amplitude to one of four different full scale ranges. Output gain control. Works with G0 to set the output amplitude to one of four different full scale ranges. Power supply for the digital sections of the IC. 3 4 CLK OUT S CLK 11,12 AVCC 13 CLK IN 6 7 S DATA IN S ENABLE 14 Serial interface enable control. A logic high on this pin allows data to be entered into the latch. 15 8 SHDN A logic high on this pin causes the output of the generator to shut off and places the IC in a low power standby mode. G0 G1 16 DVCC 2 ML2037 ABSOLUTE MAXIMUM RATINGS Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. AVCC, DVCC ................................................................................. 7V Voltage on any other pin .... AGND - 0.3V to AVCC + 0.3V Input Current ........................................................ ±25mA Junction Temperature .............................................. 150ºC Storage Temperature Range ...................... –65ºC to 150ºC Lead Temperature (Soldering, 10 sec) ..................... 260ºC Thermal Resistance (qJA) Plastic DIP ....................................................... 80ºC/W SOIC .............................................................. 105ºC/W OPERATING CONDITIONS Temperature Range ML2037CX ................................................. 0ºC to 70ºC ML2037IX ............................................... -40ºC to 85ºC AVCC, DVCC Range .................................. 4.75V to 5.25V ELECTRICAL CHARACTERISTICS Unless otherwise specified, AVCC = DVCC = 4.75V to 5.25V, SHDN = 0V, CLK IN = 25.6MHz (crystal) or 32MHz (external clock), CL = 50pF, RL = 1kW, TA = Operating Temperature Range (Note 1) SYMBOL OUTPUT HD Harmonic Distortion (2nd and 3rd Harmonic) SND Signal to Noise + Distortion 20Hz to 31.25kHz 31.25kHz to 500kHz 1kHz to 31.25kHz, fOUT BW < 31.25kHz 31.35kHz to 500kHz, fOUT BW < 500kHz Gain Error fOUT