LTC2904 Linear Technology, LTC2904 Datasheet
LTC2904
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LTC2904 Summary of contents
Page 1
... The LTC tended for systems with two supply voltages. The dual supply monitors have a common reset output with delay (200ms for the LTC2904 and adjustable using an external capacitor for the LTC2905). This product provides a precise, space-conscious and micropower solution for supply monitoring. ...
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... LTC2904/LTC2905 ABSOLUTE AXI U RATI GS Terminal Voltages V1, V2 ..................................................... –0. S1, S2, TOL .............................. –0. RST ......................................................... –0. RST (LTC2904) ....................................... –0. TMR (LTC2905) ...................................... –0. PACKAGE/ORDER I FOR ATIO TOP VIEW GND 1 8 TOL RST RST/TMR DDB8 PACKAGE 8-LEAD (3mm × ...
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... Note 6: The input current to the three-state input pins are the pull-up and the pull-down current when the pins are either set GND respectively. In the open state, the maximum leakage current GND permissible is 10µA. LTC2904/LTC2905 MIN TYP MAX ● ...
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... LTC2904/LTC2905 W TYPICAL PERFOR A CE CHARACTERISTICS Specifications are 25°C unless otherwise noted Threshold Voltage vs Temperature 4.75 4.70 5% 4.65 4.60 7.5% 4.55 4.50 4.45 10% 4.40 4. –50 – TEMPERATURE (°C) 1.8V Threshold Voltage vs Temperature 1.705 5% 1.685 1.665 7.5% 1.645 1.625 1.605 10% 1.585 www.DataSheet4U.com 1.565 25 50 –50 – TEMPERATURE (°C) ...
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... TOL = PULL- RST AT 150mV RST AT 50mV SUPPLY VOLTAGE, V 29045 G16 LTC2904/LTC2905 Reset Time Out Period (t vs Capacitance (C 10000 1000 100 10 1 0.1 100 10p 100p RTX TMR 29045 G11 RST Output Voltage vs V1 ...
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... LTC2904/LTC2905 W TYPICAL PERFOR A CE CHARACTERISTICS Specifications are 25°C unless otherwise noted. A RST Output Voltage Low ( RST Pull-Down Current (I ) RST 1 1.6 25°C 85° TOL = V1 1.4 NO PULL-UP R –40°C 1.2 1.0 0.8 0.6 0.4 0 RST PULL-DOWN CURRENT, I (mA) RST RST Pull-Up Current (I ...
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... Bypass this pin to ground with a 0.1µF CC (or greater) capacitor. RST (Pin 2/Pin 3): (LTC2904 Only) Reset Logic Output. When all voltage inputs are above the reset threshold for at least the programmed delay time, this pin pulls low. This pin has a weak pull- ...
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... LTC2904/LTC2905 W BLOCK DIAGRA LTC2905 V1 POWER DETECT V2 BAND GAP REFERENCE DIAGRA www.DataSheet4U.com RST RST 8 – RESISTOR NETWORK – + THREE-STATE DECODER Monitor Timing X RTX RST TMR V CC 6µA RESET PULSE GENERATOR RST GND 2905 BD TOL 1V 1V ...
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... reaches 1V during power-up, the RST output asserts low. V also powers the drive circuits for the RST pin in the CC LTC2904. Therefore, RST weakly pulls high when reaches at least 1V. Threshold programming is complete when V1 reaches at least 2.17V. After programming, if either falls www.DataSheet4U.com ...
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... Reset threshold accuracy is of the utmost importance in a supply sensitive system. Ideally such a system should not reset while supply voltages are within a specified margin below the rated nominal level. Both of the LTC2904/ LTC2905 inputs have the same relative threshold accu- racy. The specification for LTC2904/LTC2905 is ±1.5% of the programmed nominal input voltage (over the full operating temperature range) ...
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... RST and RST pins: t RISE where R Notice that this pull-up transistor is modeled as a 6µA current source in the Block Diagram as a typical represen- tation. The on-resistance as a function of the V voltage (for V LTC2904/LTC2905 of at least 1V guarantees 0.4V at RST. However ≈ 2.2 • R • ...
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... V2 V1 1.2V LTC2904 RST S2 0.1µF SYSTEM RST S1 RESET GND TOL 3.3V, 1.2V Dual Supply Monitor with LED Power Good Indicator, 7.5% Tolerance and Adjustable Timer 1. LTC2904 S2 RST 0.1µF S1 RST GND TOL 2.5V 0.1µF 2904 TA02 3.3V 510Ω LED 0.1µF SYSTEM RESET 2905 TA03 sn29045 29045fs ...
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... Dual Supply Monitor with Voltage Margining for Automated On-Board Testing 5V 3. LTC2905 IN S1 SUPPLY 0.1µF CONTROLLER THREE-STATE S2 TOL 1. LTC2904 S2 RST 0.1µF S1 TOL GND RST LTC2904/LTC2905 SYSTEM LOGIC V2 0.1µF TMR 22nF GND RST 29045 TA06 3.3V 10k 0.1µF SYSTEM RESET 2904 TA04 sn29045 29045fs 13 ...
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... LTC2904/LTC2905 PACKAGE DESCRIPTIO 0.61 ±0.05 (2 SIDES) 2.50 ±0.05 1.15 ±0.05 0.25 ± 0.05 0.50 BSC 2.20 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING CONFORMS TO VERSION (WECD-1) IN JEDEC PACKAGE OUTLINE M0-229 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5 ...
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... U 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) 0.80 – 0.90 1.00 MAX 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) LTC2904/LTC2905 2.90 BSC (NOTE 4) PIN ONE ID 0.22 – 0.36 0.65 BSC 8 PLCS (NOTE 3) 0.01 – 0.10 1.95 BSC TS8 TSOT-23 0802 sn29045 29045fs 15 ...
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... LTC2904/LTC2905 TYPICAL APPLICATIO 1.2V 0.1µF 22nF RELATED PARTS PART NUMBER DESCRIPTION LTC690 5V Supply Monitor, Watchdog Timer and Battery Backup LTC694-3.3 3.3V Supply Monitor, Watchdog Timer and Battery Backup LTC699 5V Supply Monitor and Watchdog Timer LTC1232 5V Supply Monitor, Watchdog Timer and Push-Button Reset LTC1326/LTC1326-2.5 Micropower Precision Triple Supply Monitor for 5V/2 ...