ltc2950-1 Linear Technology Corporation, ltc2950-1 Datasheet
ltc2950-1
Related parts for ltc2950-1
ltc2950-1 Summary of contents
Page 1
... FEATURES n Adjustable Push Button On/Off Timers n Low Supply Current: 6μA n Wide Operating Voltage Range: 2.7V to 26V n EN Output (LTC2950-1) Allows DC/DC Converter Control EN Output (LTC2950-2) Allows Circuit Breaker n Control n Simple Interface Allows Graceful μP Shut Down High Input Voltage PB Pin with Internal Pull Up ...
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... LTC2950-1/LTC2950-2 ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltage (V ) ..................................– 0.3V to 33V IN Input Voltages PB .............................................................– 33V ONT ......................................................– 0.3V to 2.7V OFFT ......................................................– 0.3V to 2.7V KILL .........................................................– 0. Output Voltages INT .........................................................– 0.3V to 10V EN/EN ....................................................– 0.3V to 10V PIN CONFIGURATION TOP VIEW GND 1 8 ONT ...
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... Note 5: The enable lock out time is designed to allow an application to properly power down such that the next power up sequence starts from a consistent powered down confi guration ignored during this lock out time. This time delay does not include DB, ON ONT LTC2950-1/LTC2950-2 MIN TYP MAX l 2.7 26.4 l ...
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... LTC2950-1/LTC2950-2 TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Temperature 26 – –25 TEMPERATURE (°C) 2950 G01 Turn On Debounce Time (t DB ONT External Capacitor ONT 10000 T = 25° 3.3V IN 1000 100 100 ONT EXTERNAL CAPACITOR (nF) ...
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... TYPICAL PERFORMANCE CHARACTERISTICS PB Voltage vs External PB Resistance to Ground 300 V = 3.3V IN 250 200 T A 150 100 EXTERNAL PB RESISTANCE TO GROUND (kΩ) EN (LTC2950-1) Voltage 25°C A 100k PULL-UP FROM 0.8 0.6 0.4 0 EN/EN V 500 400 = 100°C 300 T = 25°C A 200 T = –45°C ...
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... INT may optionally be tied to KILL to release the enable output immediately after the turn-off event has been detected (INT = low). EN (LTC2950-1, Pin 6/Pin 7): Open Drain Enable Output. This pin is intended to enable system power as- serted high after a valid PB turn on event released low if: a) KILL is not driven high (by μ ...
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... BLOCK DIAGRAM V IN REGULATOR 2.7V TO 26.4V 2.4V 100k PB 0.8V GND TIMING DIAGRAMS 2.4V OSCILLATOR LOGIC DEBOUNCE OSCILLATOR ONT t KILL(PW) KILL t KILL(PD) EN/EN LTC2950-1/LTC2950-2 0.6V 2950 BD OFFT 2950 TD01 EN/EN KILL INT 295012fc 7 ...
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... LTC2950-1/LTC2950-2 TIMING DIAGRAMS (LTC2950-1) (LTC2950-2) OFFT (LTC2950-1) (LTC2950- & KILL IGNORED DB, ON ONT KILL, ON BLANK 16 CYCLES EN EN Power On Timing PB PB IGNORED t t DB, OFF OFFT 16 CYCLES INT t KILL, OFF DELAY EN EN Power Off Timing, KILL > 0.6V 2950 TD02 2950 TD03 ...
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... Note that the KILL input can be pulled low (thereby releasing the enable output) at any time after t Simplifi ed Power On/Off Sequence Figure 1 shows a simplifi ed LTC2950-1 power on and power off sequence. A high to low transition the power on sequence. This diagram does not show any bounce on PB ...
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... LTC2950-1/LTC2950-2 APPLICATIONS INFORMATION DB, ON ONT ONT OFFT INT KILL EN Figure 1. Simplifi ed Power On/Off Sequence for LTC2950-1 POWER & KILL IGNORED t t KILL, ON BLANK DB, OFF <t KILL, OFF DELAY t ABORT DB, ON ONT 512ms ...
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... KILL releases enable, the internal 256ms timer ignores the PB pin. This is shown as t LTC2950-1, LTC2950-2 VERSIONS The LTC2950-1 (high true EN) and LTC2950-2 (low true EN) differ only by the polarity of the EN/EN pin. Both ver- sions allow the user to extend the amount of time that the PB must be held low in order to begin a valid power on/off sequence ...
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... V IN OUT LT1767-3.3 SHDN R1 10k C4 0.1μF INT μP KILL (OPEN DRAIN) 2950 F05 OUT LT1767-3.3 SHDN LTC2950-1 INT PB KILL GND ONT OFFT ONT OFFT 0.033μF 0.033μF *OPTIONAL Figure 6. No μP Application 3.3V R1 100k + C3* 0.01μF 2950 F06 295012fc ...
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... V IN TRACE CAPACITANCE 5k LTC2950-1 PB NOISE TRACE C5 INDUCTANCE 0.1μF GND DETAILS OMITTED FOR CLARITY Figure 8. Noisy PB Trace LTC2950-1/LTC2950-2 V OUT V ,TRIP POINT = 6V OUT R1 909k 1% OPTIONAL GLITCH FILTER CAPACITOR R4 C3* 100k 0.1μF 1% 2950 F07 EN INT KILL ONT OFFT ...
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... MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 14 Reverse Battery Protection To protect the LTC2950 from a reverse battery connec- tion, place a 1k resistor in series with the V Figure 10). LTC2950-1/ LTC2950 2.4V R7 ...
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... TS8 Package 8-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1637) 0.65 REF 1.22 REF 1.50 – 1.75 2.80 BSC 1.4 MIN (NOTE 4) 0.65 BSC 0.80 – 0.90 1.00 MAX 0.09 – 0.20 (NOTE 3) LTC2950-1/LTC2950-2 2.90 BSC (NOTE 4) PIN ONE ID 0.22 – 0.36 8 PLCS (NOTE 3) 0.01 – 0.10 1.95 BSC TS8 TSOT-23 0802 295012fc 15 ...
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... FAX: (408) 434-0507 ● LT1761-1.8 910k 1k SHDN 0.1μF LTC2950-1 INT PB KILL GND ONT OFFT ONT OFFT 0.033μF 0.033μF *OPTIONAL Figure 10. Reverse Battery Protection COMMENTS Adjustable RESET, 10-Lead MSOP and 3mm × 3mm DFN Packages Adjustable RESET and Tolerance, 8-Lead SOT-23 and 3mm × ...