LTC6992-4 Linear Technology, LTC6992-4 Datasheet

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... Duty Cycle = The four versions differ in their minimum/maximum duty cycle. Note that a minimum duty cycle limit maximum duty cycle limit of 100% allows oscillations to stop at the extreme duty cycle settings. DEVICE NAME LTC6992-1 LTC6992-2 LTC6992-3 LTC6992-4 MOD 0.5V/DIV + V C1 OUT 0.1μF 1V/DIV www ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 ABSOLUTE MAXIMUM RATINGS + Supply Voltage ( GND .........…………………….6V Maximum Voltage On Any Pin .............................(GND – 0.3V) ≤ V Operating Temperature Range (Note 2) LTC6992C ................................................ 0°C to 70°C LTC6992I .............................................–40°C to 85°C LTC6992H .......................................... –40°C to 125°C ...

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... V to 0.8 • V MOD SET SET V < 0.2 • > 0.8 • V MOD SET MOD SET LTC6992-1/LTC6992-3, POL = MOD LTC6992-2/LTC6992-4, POL = MOD LTC6992-1/LTC6992-4, POL = MOD LTC6992-2/LTC6992-3, POL = MOD MASTER OUT DIV LTC6992-1/LTC6992-2/ www ...

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... V = 2.25V + R = ∞ 800k 5.5V L SET 16, 384 + DIV V = 2.25V LTC6992-1/LTC6992-4, POL = 100% LTC6992-2/LTC6992-3, POL = 95% LTC6992-1/LTC6992-3, POL = LTC6992-2/LTC6992-4, POL = Deviation from Ideal + (DIVCODE + 0.5)/16 DIV + –1mA OUT I = –16mA OUT + –1mA ...

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... I SET Note 11: Jitter is the ratio of the peak-to-peak deviation of the period to the mean of the period. This specification is based on characterization and is not 100% tested. LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992 2.25V to 5.5V MOD SET MIN ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 TYPICAL PERFORMANCE CHARACTERISTICS otherwise noted. Frequency Error vs Temperature 3 GUARANTEED MAX OVER TEMPERATURE 50k SET 3 PARTS 1 0 –1 –2 GUARANTEED MIN OVER TEMPERATURE –3 –50 – 100 TEMPERATURE (°C) 6992 G01 Frequency Error vs R SET ...

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... R (k) SET 6992 G14 > 1 Duty Cycle Error vs R SET LTC6992-2/LTC6992 MOD SET LTC6992-2/LTC6992 MOD SET 100 200 400 800 R (k) SET 6992 G17 SET 400 800 6992 G12 SET 400 ...

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... GUARANTEED MIN –5 100 125 –50 – TEMPERATURE (°C) 6992 G22 > 1 Duty Cycle Clamps LTC6992-2/LTC6992 MOD SET LTC6992-2/LTC6992 GND MOD – 100 125 TEMPERATURE (°C) 6992 G25 75 100 125 6992 G20 75 100 ...

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... DIVCODE 6992 G27 / V N > 1 Duty Cycle vs V SET DIV 100 LTC6992-1/LTC6992 LTC6992-2/ 70 LTC6992 DIVCODE = 11 LTC6992- PARTS LTC6992 0.2 0.4 0 (V/V) MOD SET 6992 G30 N > 1 Duty Cycle Error vs Ideal ...

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... LTC6992-2/LTC6992-3 3 PARTS 0.804 0.836 0.868 V /V (V/V) MOD SET Linearity Near 5% Duty Cycle 12 DIVCODE = 4 11 LTC6992-2/LTC6992-4 3 PARTS 0.084 0.116 0.148 V /V (V/V) MOD SET N > 1 Duty Cycle Drift DIV vs Supply 0.5 DIVCODE = 4 ...

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... G47 Rise and Fall Time vs Supply Voltage 3.0 C LOAD 2.5 2.0 t RISE 1.5 t FALL 1.0 0 SUPPLY VOLTAGE (V) LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992 3.3V 200k, and T = 25°C, unless SET A Jitter vs Frequency 2.0 PEAK-TO-PEAK PERIOD 1.8 DEVIATION MEASURED OVER 30s INTERVALS 1 0.5 MOD SET 1.4 1.2 + ÷ ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 TYPICAL PERFORMANCE CHARACTERISTICS otherwise noted. Typical Start-Up, POL = 1V/DIV OUT 500μs 1V/DIV 100μs/DIV + V = 2.5V DIVCODE = 3 (÷64 50k SET V = 0.3V (~25% DUTY CYCLE) MOD 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 0.1μ ...

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... DISABLE OUTPUT UNTIL SETTLED POR VOLTAGE LIMITER + – REF – SET GND LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992-4 + with an output resistance of approximately POL OUTPUT POLARITY PULSE WIDTH MODULATOR V – 0.1•V MOD(LIM) SET DUTY CYCLE = 0.8•V OUT SET ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 OPERATION The LTC6992 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% under typical conditions 1MHz • 50k • f MASTER ...

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... V INCREASING V DIV Figure 2. Frequency Range and POL Bit vs DIVCODE LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992-4 R2 (kΩ) V DIV Short ≤0.03125 ±0.015 102 0.09375 ±0.015 182 0.15625 ±0.015 280 0.21875 ±0.015 392 0.28125 ±0.015 523 0.34375 ± ...

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... V (approximately 0.14V to 0.86V). SET The LTC6992-3 and LTC6992-4 complete the family by providing one-sided clamping. The LTC6992-3 allows 0% to 95% duty cycle, and the LTC6992-4 allows 5% to 100% duty cycle. 16 Output Polarity (POL Bit) The duty cycle equation describes a proportional transfer function, where duty cycle increases as V ...

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... OPERATION POL = 1 forces a simple logic inversion changes the duty cycle range of the LTC6992-3 (making it 100% to 5%) and LTC6992-4 (making it 95% to 0%). These transfer functions are detailed in Figure 4. 100 0.1 MOD SET POL = 1 POL = 0.9 MOD SET ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 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 LTC6992 places a priority on eliminating any “wandering” in the DIVCODE. The typical delay depends on the difference between the old and new DIVCODE settings and is proportional to the master oscillator period ...

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... GND or V (0% or 100% duty cycle, respectively), select the LTC6992-1. The LTC6992-3 and LTC6992-4 clamp the duty cycle at only one end of the control range, allowing the output to stop oscillating at the other extreme. If POL = 1 the clamp will swap from low duty cycle to high, or vice-versa. Refer to Table 2 and Figure 4 for assistance in selecting the proper version ...

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... Since 625k is not available as a standard 1% resistor, substitute 619k if a 0.97% frequency shift is acceptable. Otherwise, select a parallel or series pair of resistors such as 309k and 316k to attain a more precise resistance. The completed design is shown in Figure 7. V MOD OUT MOD LTC6992-4 2.25V TO 5.5V + GND V SET DIV 6992 F07 R ...

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... Following a ±100mV step change in V duty cycle takes approximately TBD master clock cycles Figure 10. PWM Frequency Response Figure 11. PWM Settling Time LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 (TBD • t MASTER An example is shown in Figure 11. Frequency Modulation and Settling Time In addition to pulse-width modulation, the LTC6992 can – ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 APPLICATIONS INFORMATION Power Supply Current The power supply current varies with frequency, supply voltage and output loading. It can be estimated under any condition using the following equation (DIVCODE = 0 or 15): DIV ( + ≈ V • 39pF + C I • f S(TYP) OUT ...

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... N • 1.125μs • ON DIV INCREASES, t INCREASES AND DUTY CYCLE IN OUT DECREASES (BECAUSE POL = 1) TO MAINTAIN A CONSTANT t FOR CONSTANT OFF-TIME, JUST CHANGE DIVCODE SO POL = 0. LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992 0.1μ MOD OUT + GND V SET DIV ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 TYPICAL APPLICATIONS Digitally Controlled Duty Cycle with Internal V V OUT ANALOG PWM DUTY CYCLE CONTROL MOD (0V TO 1V) LTC6992-X GND SET R SET 24 Reference Variation Eliminated REF MOD OUT LTC6992-X GND + V + SET DIV 1/2 R 6992 TA03 LTC6078 SET – REF ...

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... 50k DIV f = 10kHz R3 130k PWM OUTPUT FOR ISOLATED MEASUREMENT +1% DUTY CYCLE CHANGE PER DEGREE C –10°C TO 65°C RANGE WITH OPTO-ISOLATOR (DC: 15% TO 95%) LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992-4 ANALOG PWM MOD OUT (0V TO 1V) LTC6992-X + GND V SET DIV R R SET2 ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 TYPICAL APPLICATIONS Motor Speed/Direction Control for Full H-Bridge (Locked Anti-Phase Drive) INPUT 300k Motor Speed/Direction Control for Full H-Bridge (Sign/Magnitude Drive) INPUT MOD LTC6992-2 GND SET R3 300k 26 A1 2.6kHz 95% PWM CLOCKWISE 50 STOPPED ...

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... MOD OUT + LT1490 LTC6992 GND V 10k SET DIV 6992 TA10 R SET 316k DIV f = 10kHz OUT LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992-4 OUTPUT DUTY CYCLE = K • 100 1000k R2 186k OUTPUT DUTY CYCLE = (1–K) • 100 1000k R2 186k 69921234p 27 ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 TYPICAL APPLICATIONS 2. 130k R6 8.66k 2ms SERVO CONTROL POT 10k 1ms Direct Voltage Controlled PWM Dimming 0 to 15000 Cd/m V DIMMING 28 Ratio Control Servo Pulse Generator R6 9.09k 0.22μF 1μF 90. – MOD OUT + LT1490 LTC6992-1 + GND V SET ...

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... SLOW PWM CONTROLS 0 TO 6000 2 Cd/m BRIGHTNESS MOD OUT LTC6992-1 + GND DIV3 1M 0.1μF SET DIV R DIV4 681k SET2 0–100 4096 6992 TA13 DIV f = 100kHz OUT LTC6992-1/LTC6992-2/ www.DataSheet4U.com LTC6992-3/LTC6992-4 2 Brightness) 3. LED A1 LT3518UF PWM LUMILEDS LXHL-BW02 D1 D2 69921234p 29 ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 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 30 DCB Package 6-Lead Plastic DFN (2mm × 3mm) (Reference LTC DWG # 05-08-1715 Rev A) 0.70 ±0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 1.35 ± ...

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... LTC6992-1/LTC6992-2/ S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636 Rev B) 1.22 REF 1.50 – 1.75 2.80 BSC 1.4 MIN (NOTE 4) 0.95 BSC 0.80 – 0.90 1.00 MAX 0.09 – 0.20 (NOTE 3) www.DataSheet4U.com LTC6992-3/LTC6992-4 2.90 BSC (NOTE 4) PIN ONE ID 0.30 – 0.45 6 PLCS (NOTE 3) 0.01 – 0.10 1.90 BSC S6 TSOT-23 0302 REV B 69921234p 31 ...

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... LTC6992-1/LTC6992-2/ LTC6992-3/LTC6992-4 TYPICAL APPLICATION ANALOG PWM DUTY CYCLE MOD OUT CONTROL LTC6992-1 5V (0V TO 1V) + GND V SET DIV 102k C1: KEMET C0806C225K4RAC C2: KEMET C1206C475K3RAC C3, C4: MURATA GRM21BR71H104KA01B C5: MURATA GRM21BR71H224KA01B D1: DIODE DFL5160 L1: TOKO B992A5-6RBN LEDS: LUXEON I (WHITE) M1: ZETEX ZXMP6A13FTA RELATED PARTS PART NUMBER ...