LTC6991 Linear Technology, LTC6991 Datasheet
LTC6991
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LTC6991 Summary of contents
Page 1
... The reset pin can also be used to prevent the output from oscillating. The RST and OUT pins can be configured for active-low or active-high operation using a polarity function. The LTC6991 is available in the 6-lead SOT-23 (ThinSOT) package or a 6-lead 2mm × 3mm DFN. 1µs PULSE WIDTH OUT ...
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... Specified Temperature Range (Note 3) LTC6991C ................................................ 0°C to 70°C + ≤ 0.3V) LTC6991I .............................................–40°C to 85°C PIN LTC6991H .......................................... –40°C to 125°C Junction Temperature ........................................... 150°C Storage Temperature Range .................. –65°C to 150°C Lead Temperature (Soldering, 10 sec) S6 Package ........................................................... 300°C 6 OUT 7 5 GND ...
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... DIV + R = ∞ 50k V = 5.5V L SET + V = 2.25V + R = ∞ 100k V = 5.5V L SET + V = 2.25V + R = ∞ 800k V = 5.5V L SET + V = 2.25V LTC6991 + = 2.25V to 5.5V, RST = 0V, DIVCODE = MIN TYP MAX 1.024m 34,360 29.1µ 977 ±0.8 ±1.5 ±2.2 l ±0.005 l 0.23 0.55 l 0.06 0. 0.4 • f OUT 1 0.97 1.00 1.03 l ± 800 ...
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... The LTC6991C is designed, characterized and expected to meet specified performance from –40°C to 85°C but it is not tested or QA sampled at these temperatures. The LTC6991I is guaranteed to meet specified performance from –40°C to 85°C. The LTC6991H is guaranteed to meet specified performance from –40°C to 125°C. ...
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... SET 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 REFERENCED 10µA SET –1 SUPPLY (V) 6992 G07 LTC6991 Frequency Error vs Temperature 3 GUARANTEED MAX OVER TEMPERATURE 800k SET 3 PARTS 1 0 –1 GUARANTEED MIN OVER TEMPERATURE –2 –3 –50 – 100 125 TEMPERATURE (°C) ...
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... DataSheet.in LTC6991 Typical perForMance characTerisTics + V = 3.3V 200k 25°C unless otherwise noted. SET A Supply Current vs Supply Voltage 150 R = 50k SET 125 100 R = 100k SET R SET 75 R SET SUPPLY VOLTAGE (V) Supply Current vs R SET 150 125 + 100 + V = 3.3V 75 ...
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... RST high allows the output to oscillate. LTC6991 Typical Start-Up with POL = 1V/DIV 1µ WIDE MASTER INITIAL PULSE 500µs OUT 1V/DIV + V = 2.5V 250µs/DIV 6991 G19 DIVCODE = 50k SET voltage. SET + V RST OUT LTC6991 + V + GND 0.1µF SET DIV R 6991 PF R2 SET 6991p ...
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... DataSheet.in LTC6991 pin FuncTions GND (Pin 5/Pin 2): Ground. Tie to a low inductance ground plane for best performance. OUT (Pin 6/Pin 6): Oscillator Output. The OUT pin swings + from GND to V with an output resistance of approximately block DiagraM DIV 4-BIT A/D 4 CONVERTER R2 HALT OSCILLATOR IF I < ...
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... DataSheet.in operaTion The LTC6991 is built around a master oscillator with a 1MHz maximum frequency. The oscillator is controlled by the SET pin current (I SET 1MHz • 50k conversion factor that is accurate to ±0.8% under typical conditions MHz MASTER t MASTER A feedback loop maintains V as the primary means of controlling the output frequency. ...
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... DataSheet.in LTC6991 operaTion Table 1. DIVCODE Programming DIVCODE POL 10000 1000 100 10 0.1 0.01 0.001 0 N RECOMMENDED t DIV OUT 1 1.024ms to 16.384ms 8 8.192ms to 131ms 64 65.5ms to 1.05sec 512 524ms to 8.39sec 4,096 4 ...
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... DataSheet.in operaTion RST Pin and Polarity (POL) Bit The RST pin controls the state of the LTC6991’s output as seen on the OUT pin. The active/inactive voltage levels depend on the POL bit setting. Table 2. Output States POL BIT RST PIN Each period of the LTC6991’s internal oscillator clocks the output state latch (see Block Diagram) ...
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... Subsequent pulses will also be skipped until RST = 0. In inverted operation (POL = 1), the start-up sequence is similar. However, the LTC6991 does not know the correct DIVCODE setting when first powered up, so the output . The OUT pin defaults low ...
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... Figure 8. Start-Up Timing Diagram (RST = 1, POL = 0) t OUTPUT DISABLED FOR START INTEGER MULTIPLE OF t OUT t MASTER Figure 9. Start-Up Timing Diagram (RST = 0, POL = START OUT t MASTER Figure 10. Start-Up Timing Diagram (RST = 1, POL = 1) LTC6991 6991 F07 6991 F08 6991 F09 6991 F10 6991p ...
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... First select the POL bit setting and N the value for the R resistor. SET Step 1: Select the POL Bit Setting The LTC6991 can operate in normal (active-high) or inverted (active-low) modes, depending on the setting of the POL bit. The best choice depends on the the application. Step 2: Select the N Frequency Divider Value ...
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... If the LTC6991 is enabling a switching regulator that can operate on supplies greater than 5.5V, it will be necessary to limit the supply voltage provided to the LTC6991. If the LTC6991 output is not heavily loaded, and if a large R SET larger than 100µ simple regulator circuit can be constructed using a Zener diode ...
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... Characteristics). This allows an RC time constant at the RST input to generate a delay that is nearly independent of the supply voltage. A simple application of this technique allows the LTC6991 output to reset itself, producing a well-controlled pulse once each cycle. Figures 13a and 13b show circuits that produce approximately 1µs pulses once a minute. The only difference is in the POL bit setting, which controls whether the pulse is positive or negative ...
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... I S TYP ( ) Supply Bypassing and PCB Layout Guidelines The LTC6991 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. Adequate supply bypassing and proper –3dB SET PCB layout are important to ensure this ...
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... GND pin connection to the ground plane and the C1 connection to the ground plane are recommended to minimize the inductance. Capacitor C1 should be a 0.1µF ceramic capacitor. 2. Place all passive components on the top side of the board. This minimizes trace inductance. RST OUT LTC6991 + GND V SET DIV R SET + ...
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... Radio Control Servo Reference Pulse Generator 5V 20ms FRAME RATE R7 GENERATOR 20ms PERIOD 10k RST OUT LTC6991 5V + GND 0.01µF 976k SET DIV R6 R5 121k 102k LTC6991 COTO 1022 RELAY 9001-12-01 C2 0.1µF 1.5ms REFERENCE PULSE TRIG OUT 1.5ms PULSE LTC6993 GND 0.1µF 1M SET DIV ...
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... GND 0.1µF 1M SET DIV R10 R9 237k 392k 50k –15V IN Isolated AC Load Flasher 5V 0.1µ 215 MOC3041M RST OUT R1 LTC6991 SET DIV 5V ZERO GND R2 CROSSING 392k 2 ISOLATION BARRIER = 7500V M2 Si4435DY 15V OUT R6 20k Si9410 5V M4 Si4435DY R1 R3 100k – ...
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... OFF 182k 2s 280k 5s 15s 30s 113k 133k OFF Interval (Wiper) Timer + RST OUT LTC6991 + + V GND V 0.1µF 1M SET DIV LTC6991 TRIG OUT OUTPUT 2s LTC6993 GND V 0.1µ SECONDS TO 4 MINUTES SET DIV 383k 681k 2s 6991 TA06 t INTERVAL 6991p ...
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... DataSheet.in LTC6991 package DescripTion 3.55 0.05 2.15 0.05 DCB Package 6-Lead Plastic DFN (2mm × 3mm) (Reference LTC DWG # 05-08-1715 Rev A) 0.70 0.05 1.65 0.05 (2 SIDES) PACKAGE OUTLINE 0.25 0.05 0.50 BSC 1.35 0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 2.00 0.10 (2 SIDES) 3.00 0.10 (2 SIDES) PIN 1 BAR TOP MARK (SEE NOTE 6) 0.200 REF 0.75 0.05 0.00 – 0.05 NOTE: 1 ...
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... 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. LTC6991 2.90 BSC (NOTE 4) PIN ONE ID 0.30 – ...
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... TimerBlox: Monostable Pulse Generator (One Shot) LTC6994 TimerBlox: Delay Block/Debouncer Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● Intervalometer for Time-Lapse Photography R PW 100k RST OUT C PW LTC6991 33µF + GND V R1A R S3 332k 95.3k SET DIV 8SEC ...