LTC6990IDCB#TRPBF Linear Technology, LTC6990IDCB#TRPBF Datasheet
LTC6990IDCB#TRPBF
Specifications of LTC6990IDCB#TRPBF
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LTC6990IDCB#TRPBF Summary of contents
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... Replacement for Fixed Crystal and Ceramic Oscillators n Portable and Battery-Powered Equipment L, LT, LTC and LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. TimerBlox and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. ...
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... JA EXPOSED PAD (PIN 7) CONNECTED TO GND, PCB CONNECTION OPTIONAL ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC6990CDCB#PBF LTC6990CDCB#TRPBF LTC6990IDCB#PBF LTC6990IDCB#TRPBF LTC6990HDCB#PBF LTC6990HDCB#TRPBF LTC6990CS6#PBF LTC6990CS6#TRPBF LTC6990IS6#PBF LTC6990IS6#TRPBF LTC6990HS6#PBF LTC6990HS6#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are 128 50k to 800k, R DIV SET LOAD SYMBOL PARAMETER f Output Frequency OUT Δf Frequency Accuracy (Note 4) OUT Δf Frequency Drift Over ...
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LTC6990 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are 128 25k to 800k, R DIV SET LOAD SYMBOL PARAMETER Digital I/O OE Pin Input Capacitance OE Pin Input Current V High Level ...
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TYPICAL PERFORMANCE CHARACTERISTICS Frequency Error vs R SET 25° GUARANTEED MAX OVER TEMPERATURE 2 1 TYPICAL MAX 0 90% OF UNITS TYPICAL MIN –1 –2 GUARANTEED MIN –3 OVER TEMPERATURE –4 10 100 R (kΩ) ...
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LTC6990 TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Frequency, 5V 400 RECOMMENDED RANGE EXTENDED RANGE 350 300 250 200 ÷128 150 100 FREQUENCY (kHz) Supply Current vs OE Pin Voltage 200 T = 25° ...
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TYPICAL PERFORMANCE CHARACTERISTICS Rise and Fall Time vs Supply Voltage 3.0 2.5 2.0 t RISE 1.5 t FALL 1.0 0 SUPPLY VOLTAGE (V) Typical I Current Limit vs V SET 1000 T = 25°C A SET ...
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LTC6990 PIN FUNCTIONS (DCB/S6 (Pin 1/Pin 5): Supply Voltage (2.25V to 5.5V). This sup- ply must be kept free from noise and ripple. It should be bypassed directly to the GND pin with a 0.1μF capacitor. DIV (Pin ...
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BLOCK DIAGRAM (S6 Package Pin Numbers Shown DIV 4-BIT A/D 4 CONVERTER R2 HALT OSCILLATOR – GND + DIGITAL FILTER MASTER OSCILLATOR V 1μs SET t • MCLK MASTER 50k I ...
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LTC6990 OPERATION The LTC6990 is built around a master oscillator with a 1MHz maximum frequency. The oscillator is controlled by the SET pin current (I ) and voltage (V SET 1MHz • 50k conversion factor that is accurate to ±0.8% ...
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OPERATION Table 1. DIVCODE Programming DIVCODE Hi-Z N DIV 128 8 1 128 ...
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LTC6990 OPERATION On start-up, the DIV pin A/D converter must determine the correct DIVCODE before the output is enabled not stable, it will increase the start-up time as the converter waits for a stable result. Therefore, capacitance on ...
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OPERATION Changing DIVCODE After Start-Up Following start-up, the A/D converter will continue monitoring V for changes. Changes to DIVCODE will DIV be recognized slowly, as the LTC6990 places a priority on eliminating any “wandering” in the DIVCODE. The typical delay ...
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LTC6990 APPLICATIONS INFORMATION OE OUT Figure 7. Start-Up Timing Diagram ( OUT Figure 8. Start-Up Timing Diagram ( OUT Figure 9. Start-Up Timing Diagram ( OUT Figure 10. Start-Up Timing ...
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APPLICATIONS INFORMATION Start-Up Behavior When fi rst powered up, the output is high impedance. If the output is enabled ( the end of the start-up time, the output will go low for one cycle ...
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LTC6990 APPLICATIONS INFORMATION Equation (2) can be re-written as shown below, where f is the output frequency when V CTRL frequency gain. Note that the gain is negative (the output frequency decreases as V increases). CTRL – ...
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APPLICATIONS INFORMATION The accuracy of K does depend on V VCO output frequency is controlled by the ratio The frequency error (in Hertz) due to ΔV V SET proximated by: ΔV SET Δf ≅ K • V ...
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LTC6990 APPLICATIONS INFORMATION Depending on the application’s requirements, the non- inverting VCO circuit in Figure 13 may be preferred for this wide of a frequency variation as its maximum inac- curacy due to V error is only ±9% and can ...
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APPLICATIONS INFORMATION Eliminating V Error Effects with DAC Frequency SET Control Many DACs allow for the use of an external reference. If such a DAC is used to provide the V V error is eliminated by buffering V SET the ...
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LTC6990 APPLICATIONS INFORMATION Modulation Bandwidth and Settling Time The LTC6990 will respond to changes in I bandwidth of 0.4 • f (see Figure 15). This makes it easy OUT to stabilize a feedback loop around the LTC6990, since it does ...
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APPLICATIONS INFORMATION SUPPLY BYPASSING AND PCB LAYOUT GUIDELINES The LTC6990 is a 2.2% accurate silicon oscillator when used in the appropriate manner. The part is simple to use and by following a few rules, the expected performance is easily achieved. ...
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LTC6990 TYPICAL APPLICATIONS OE OUT LTC6990 + GND V SET DIV R SET 619k Full Range VCO with Any N R VCO1 26. Full Range VCO with Any N R3 10k ...
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TYPICAL APPLICATIONS Speaker Alarm. Modulate Tone with R STEP RAMP Overvoltage Detector/Alarm. Direct Drive of Piezo Alarm 24V R A 787k R B 10.7k 400mV V 400mV 1 ALARM Direct Piezo Alarm Driver. Adjust Frequency for Maximum Alarm Sound Pressure ...
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LTC6990 TYPICAL APPLICATIONS Isolated V → F Converter Quadrature Sine Wave Oscillator. Voltage Controlled Frequency Range from 2Hz to 18kHz with 1V 51.1k 5.11k 5V 124k – A/B AGND 50/100 10k + ...
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TYPICAL APPLICATIONS 3% Linearity from –20°C (f 22k AT 25° 3964 Full Range Temperature to Frequency Converter. 16kHz to 1kHz from –20°C to 80°C 22k AT 25° 3964 Light to Frequency Converter Temperature ...
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LTC6990 PACKAGE DESCRIPTION 1.65 0.05 3.55 0.05 (2 SIDES) 2.15 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 BAR TOP MARK (SEE NOTE 6) 0.200 REF 26 DCB Package 6-Lead Plastic DFN (2mm × 3mm) (Reference LTC DWG # ...
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... MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. S6 Package ...
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... FEW MILLISECONDS (CONTROLLED BY C COMMENTS Wide Frequency Range Low Power, Wide Frequency Range Micropower, I SUPPLY 0.09% Accuracy, 110μs Start-Up Time, 105μA at 32kHz www.linear.com ● 2.25V TO 5.5V R1 976k R2 102k ). SET = 35μA at 400kHz LT 0710 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 6990f ...