LTC2951-2 Linear Technology, LTC2951-2 Datasheet
LTC2951-2
Related parts for LTC2951-2
LTC2951-2 Summary of contents
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... Low Supply Current: 6µA ■ ■ Wide Operating Voltage Range: 2.7V to 26V EN Output (LTC2951-1) Allows DC/DC Converter ■ Control ⎯ E ⎯ N Output (LTC2951-2) Allows Circuit Breaker ■ www.DataSheet4U.com Control Simple Interface Allows Graceful µP Shut Down ■ High Input Voltage ⎯ P ⎯ B Pin with Internal Pull Up ■ ...
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... LTC2951-1/LTC2951 ABSOLUTE AXI U RATI GS (Note 1) Supply Voltage (V ) ..................................– 0.3V to 33V IN Input Voltages ⎯ P ⎯ B ............................................................– 33V KILLT ....................................................– 0.3V to 2.7V OFFT .....................................................– 0.3V to 2.7V ⎯ K ⎯ I ⎯ L ⎯ L .........................................................– 0. Output Voltages ⎯ I ⎯ ⎯ N ⎯ T .........................................................– 0.3V to 10V EN/ ⎯ E ⎯ N ....................................................– 0.3V to 10V www.DataSheet4U.com ...
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... The ⎯ K ⎯ I ⎯ L ⎯ L and ⎯ P ⎯ B inputs are ignored during this period. If ⎯ K ⎯ I ⎯ L ⎯ L remains low at the end of this time period, the enable output is released, thus turning off system power. This time delay does not include t LTC2951-1/LTC2951-2 The denotes the specifi cations which apply over the full operating ● ...
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... LTC2951-1/LTC2951-2 W TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Temperature 26 www.DataSheet4U.com 0 – –25 TEMPERATURE (°C) Internal Default Turn Off Debounce Time ( DB, OFF 25° (V) IN Internal Default ⎯ K ⎯ I ⎯ L ⎯ L Turn Off ...
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... T = 100°C A 150 T = 25° –45°C A 100 EXTERNAL PB RESISTANCE TO GROUND (kΩ) 2951 G10 ⎯ E ⎯ N (LTC2951-2) Voltage 25°C A 100k PULL-UP FROM 2951 G12 IN IN ...
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... The operating range for this pin 10V. A 100k pull-up is recommended if not available in the DC/DC converter. ⎯ ⎯ E ⎯ N (LTC2951-2, Pin 6/Pin 7): Open Drain Enable Output. This pin is intended to enable system power. ⎯ E ⎯ asserted ). A capacitor to low after a valid ⎯ P ⎯ B turn-on event (t high if: a) ⎯ ...
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... W BLOCK DIAGRA V IN REGULATOR 2.7V TO 26.4V 2.4V 100k PB www.DataSheet4U.com 0.8V GND DIAGRA S 2.4V OSCILLATOR LOGIC DEBOUNCE OSCILLATOR KILLT t KILL(PW) KILL t KILL(PD) EN/EN LTC2951-1/LTC2951-2 0.6V 2951 BD OFFT 2951 TD01 EN/EN KILL INT 295112fa 7 ...
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... LTC2951-1/LTC2951 DIAGRA S (LTC2951-1) www.DataSheet4U.com (LTC2951-2) PB OFFT INT KILLT EN (LTC2951-1) EN (LTC2951- & KILL IGNORED t t DB, ON KILL, ON BLANK EN EN Power On Timing PB IGNORED t t DB, OFF OFFT 16 CYCLES t KILL, OFF DELAY Power Off Timing, ⎯ K ⎯ I ⎯ L ⎯ L > 0.6V ...
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... The reason ⎯ P ⎯ ignored is to ensure that the system is not forced off while powering on. Once the 512ms timer expires (t debounced with an internal 32ms timer. The system has now properly powered on and the LTC2951 monitors ⎯ P ⎯ B LTC2951-1/LTC2951 which can be extended ⎯ K ⎯ I ⎯ L ⎯ L OFF DELAY ) ...
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... LTC2951-1/LTC2951 APPLICATIO S I FOR ATIO DB, ON OFFT www.DataSheet4U.com INT KILL EN POWER & KILL IGNORED t t KILL, ON BLANK Figure 1. Simplifi ed Power On/Off Sequence for LTC2951 DB, ON 512ms INTERNAL TIMER TIMING EN µ ...
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... This is shown as t Figure 4. LTC2951-1, LTC2951-2 Versions The LTC2951-1 (high true EN) and LTC2951-2 (low true ⎯ E ⎯ differ only by the polarity of the EN/ ⎯ E ⎯ N pin. Both ver- sions allow the user to extend the amount of time that the ⎯ P ⎯ B must be held low in order to begin a valid power off sequence ...
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... LTC2951-1/LTC2951 APPLICATIO S I FOR ATIO High Voltage Pins and ⎯ P ⎯ B pins can operate at voltages up to 26.4V. The V IN ⎯ P ⎯ B can, additionally, operate below ground (–6V) without latching up the device. ⎯ P ⎯ B has an ESD HBM rating of ±10kV. If the push button switch connected to ⎯ P ⎯ B exhibits high leakage current, then an external pull-up resistor to V recommended ...
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... TYPICAL APPLICATIO S Power Path Switching The ⎯ E ⎯ N open drain output of the LTC2951-2 is designed to switch on/off an external power PFET. This allows a user to connect/disconnect a power supply (or battery) to its load by toggling the ⎯ P ⎯ B pin. Figure 7 shows the LTC2951-2 controlling a two cell Li-Ion battery application. The ⎯ I ⎯ N ⎯ T and ⎯ ...
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... To mitigate the effect of the board leakage, a 10k resistor recommended (see Figure 9). IN www.DataSheet4U.com 14 U Reverse Battery Protection To protect the LTC2951 from a reverse battery connec- tion, place a 1k resistor (R8) in series with the V (see Figure 10). LTC2951-1/ LTC2951 2.4V R7 10k PB EXTERNAL BOARD LEAKAGE CURRENT >2µA IF EXTERNAL PARASITIC BOARD LEAKAGE > ...
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... PACKAGE OUTLINE 0.200 REF 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) LTC2951-1/LTC2951 0.115 0.40 ± 0.10 TYP TYP 2.00 ±0.10 (2 SIDES) 0.56 ± 0.05 (2 SIDES 0.25 ± 0.05 0.75 ±0.05 0.50 BSC 2.15 ±0.05 (2 SIDES) 0 – ...
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... LTC2951-1/LTC2951-2 TYPICAL APPLICATIO BATTERY www.DataSheet4U.com RELATED PARTS PART NUMBER DESCRIPTION LTC2900 Programmable Quad Supply Monitor LTC2904/2905 Pin-Programmable Dual Supply Monitors LTC2950 Micropower Push Button On/Off Controller LTC4411 2.6A Low Loss Ideal Diode in ThinSOT LTC4412HV Power Path Controller in ThinSOT LTC4055 USB Power Controller and Li-Ion Charger ...