LTC2938IMS#TRPBF Linear Technology, LTC2938IMS#TRPBF Datasheet
LTC2938IMS#TRPBF
Specifications of LTC2938IMS#TRPBF
Related parts for LTC2938IMS#TRPBF
LTC2938IMS#TRPBF Summary of contents
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... LTC2938 monitors up to four supplies. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 6967591, 7239251, 7119714. ...
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... TAPE AND REEL LTC2938CDE#PBF LTC2938CDE#TRPBF LTC2938IDE#PBF LTC2938IDE#TRPBF LTC2938HDE#PBF LTC2938HDE#TRPBF LTC2938CMS#PBF LTC2938CMS#TRPBF LTC2938IMS#PBF LTC2938IMS#TRPBF LTC2938HMS#PBF LTC2938HMS#TRPBF LTC2939CMS#PBF LTC2939CMS#TRPBF LTC2939IMS#PBF LTC2939IMS#TRPBF LTC2939HMS#PBF LTC2939HMS#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER V Minimum Internal Operating Voltage CC V Minimum Required for Confi guration CCMINP V 5V, 5% Reset Threshold RT50 V 3.3V, 5% Reset Threshold RT33 V 2.5V, 5% ...
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LTC2938/LTC2939 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T SYMBOL PARAMETER I WDI Input Current WDI t WDI Input Pulse Width WP Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the ...
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TYPICAL PERFORMANCE CHARACTERISTICS Supply Current vs Temperature –50 – 100 TEMPERATURE (°C) 29389 G04 ...
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LTC2938/LTC2939 TYPICAL PERFORMANCE CHARACTERISTICS I vs Supply Voltage (RST) SINK 25° 0. 0. (V) 29389 G13 WDO ...
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PIN FUNCTIONS will vary depending on parasitic capacitance on the pin. Tie CWT to GND to disable the watchdog function. GND: Device Ground. NC: No Internal Connection. RST: Reset Output. Logic output with weak 6μA pull-up to V2. Pulls low ...
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LTC2938/LTC2939 BLOCK DIAGRAM VREF VPG A RESISTIVE DIVIDERS – – CRT GND WDI CWT 8 BUFFER V1 BANDGAP REFERENCE – 4 ADJUSTABLE RESET PULSE GENERATOR WDFAIL LTC2939 ...
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TIMING DIAGRAM V RST V n RST t t RST RST WDO WDI POWER-ON RESET FOLLOWED BY RESET CAUSED BY UNDERVOLTAGE EVENT. WATCHDOG OUTPUT SET HIGH, WATCHDOG INPUT = DON’T CARE V Monitor Timing RST ...
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LTC2938/LTC2939 APPLICATIONS INFORMATION Supply Monitoring The LTC2938 and LTC2939 are low power, high accuracy confi gurable four (LTC2938) and six (LTC2939) supply monitoring circuits with reset output and watchdog func- tions. Both watchdog and reset timeouts are adjustable using external ...
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APPLICATIONS INFORMATION A less accurate supervisor increases the required system voltage margin and increases the probability of system malfunction. The LTC2938 and LTC2939 ±1.5% specifi ca- tion improves the reliability of the system over supervisors with wider threshold tolerances. Monitor ...
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LTC2938/LTC2939 APPLICATIONS INFORMATION Using the Adjustable Thresholds The reference inputs on the V3 and/or V4 comparators are set to 0.5V when the positive adjustable modes are se- lected (Figure 3). The LTC2939 V5 and V6 comparators are always in positive ...
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APPLICATIONS INFORMATION Power-Down On power-down, once any of the monitor inputs drops below its threshold, RST is held at a logic low. A logic low of 0.4V is guaranteed until both V1 and V2 drop below 1V. If the bandgap ...
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LTC2938/LTC2939 APPLICATIONS INFORMATION After RST returns high, the microprocessor can poll the state of the WDO pin to determine if the reset was caused by an undervoltage condition watchdog timeout. WDO high means that the reset was ...
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TYPICAL APPLICATIONS Quad-Supply Monitor (Mode 14) with Watchdog Disabled 5V 3.3V 1.8V 12V V = 11.25V TRIP ±5V Supply Monitor (Mode 1) with Watchdog Disabled and Unused Inputs Tied High 5V – – 4.64V TRIP V1 V2 0.1μF ...
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LTC2938/LTC2939 TYPICAL APPLICATIONS Supply and Temperature Monitor (Mode 1, 5V, 3.3V, 28V, –5.2V, 12V, 100°C) 5V 3.3V 0.1μF 2150k 1% 12V 5110k 1% 28V 467k 1% –5.2V 100k 1% *PANASONIC ERTJOEV474J 5V 3.3V 2.5V 1.8V 2150k 1% 12V 124k 1% ...
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PACKAGE DESCRIPTION 3.60 0.05 2.20 0.05 1.70 0.05 0.25 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF NOTE: 1. DRAWING PROPOSED ...
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LTC2938/LTC2939 PACKAGE DESCRIPTION 5.23 (.206) MIN 0.42 0.038 (.0165 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR ...
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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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. ...
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... Adjustable Reset Timer and Tolerance, Pin-Selectable Tolerance (5%, 7.5%, 10% or 12.5%), Reset Disable for Margining, TSSOP-20 Package www.linear.com ● R3 2.15MΩ 1% 12V V = 11.25V TRIP 10k* MANUAL RESET R4 PUSHBUTTON 100k 1% *OPTIONAL RESISTOR FOR ADDED ESD PROTECTION 293839ff LT 0709 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2009 ...