LTC2938 LINER [Linear Technology], LTC2938 Datasheet
LTC2938
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LTC2938 Summary of contents
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... The 80μA supply current makes the LTC2938 and LTC2939 ideal for power conscious systems. The LTC2939 moni- tors up to six supplies and the LTC2938 monitors up to four supplies. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation ...
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... LEAD FREE FINISH 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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... 100μ SINK 2.5mA 3.3V SINK –1μ 3.3V SOURCE V = GND CWT V = 1.3V CWT C = 1500pF WT Logic Low Open Logic High LTC2938/LTC2939 MIN TYP MAX UNITS 2.6 l 4.600 4.675 4.750 l 3.036 3.086 3.135 l 2.300 2.338 2.375 l 1.656 1.683 1.710 l 1.380 1 ...
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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 device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime ...
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... Watchdog Timeout Period vs C 100 T = 25° 100m 10m 1m 100μ 10p 100p 1n 10n 100n 125 C (F) WT LTC2938/LTC2939 Transient Duration vs Comparator Overdrive 400 350 300 250 RESET OCCURS 200 ABOVE CURVE 150 100 50 0 –50 0 0.1 1 RESET COMPARATOR OVERDRIVE (% OF V 29389 G05 ...
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... LTC2938/LTC2939 TYPICAL PERFORMANCE CHARACTERISTICS I vs Supply Voltage (RST) SINK 25° 0. 0. (V) 29389 G13 WDO Pull-Up Current 25°C A WDO = GND (V) PIN FUNCTIONS CRT: Reset Timeout Capacitor. Attach an external capaci- tor ( GND to set a reset timeout of 2ms/nF ...
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... V5: Adjustable Voltage Input 5 for LTC2939. High imped- ance comparator input with 0.5V typical threshold. Tie unused. V6: Adjustable Voltage Input 6 for LTC2939. High imped- ance comparator input with 0.5V typical threshold. Tie unused. LTC2938/LTC2939 V : Threshold Select Input. Connect to an external 1% PG resistive divider between V and GND to select one of REF sixteen combinations of voltage thresholds (see Table 1) ...
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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 2μ WATCHDOG TRANSITION DETECT 2μ POWER V CC DETECT V2 6μA RST V2 22μA 6μ ...
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... WATCHDOG OUTPUT REMAINS LOW, WATCHDOG OUTPUT RESET OUTPUT PULLS LOW AGAIN AFTER LOW TIME SHORTENED ONE WATCHDOG TIMEOUT PERIOD. BY UNDERVOLTAGE WATCHDOG OUTPUT CLEARED BY EVENT DURING RESET UNDERVOLTAGE EVENT. TIMEOUT. LTC2938/LTC2939 293839 TD01 t t RST RST t WD 293839 TD02 WATCHDOG INPUT NOT ...
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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 capacitors. Single-pin confi guration selects one of sixteen input voltage monitor combinations ...
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... Upon power-up, the LTC2938 or LTC2939 enters a con- fi guration period of approximately 150μs during which the voltage on the V is confi gured to the desired input combination. Do not add capacitance to the V programming, the comparators are enabled and supply monitoring begins. ...
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... − • TRIP REF REF R 4 LTC2938/LTC2839 V REF TRIP Figure 4. Setting the Negative Adjustable Trip Point negative adjustable application, the minimum value for R4 is limited by the sourcing capability of V With no other load 210 ...
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... The WDO and RST pins can be pulled to voltages higher than V2 by external pull-up resistors. Watchdog Application Figure 5 shows a typical application for the LTC2938/ LTC2939. The C dog timeout period for optimal software execution. If the software malfunctions and the state of the WDI pin ...
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... If the WDO pin is low, the system reset was caused by watchdog timeout. The microproces- sor can then change the state of WDI to clear the WDO latch. If the microprocessor fails to do so, the LTC2938/ LTC2939 will alternate between t and RST will be pulled low for t RST timeout. WDO remains low until the microprocessor fl ...
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... V REF R1 9.53k R4 1% 100k GND CRT R2 93. 47nF 293839 TA02 V1 0.1μ 464k V3 1% LTC2938 V4 RST R4 121k 1% WDO V REF R1 93. WDI PG GND CRT CWT R2 9.53k 47nF 293839 TA03 LTC2938/LTC2939 SYSTEM RST LOGIC WDO WDI CWT RT SYSTEM LOGIC 293839ff 15 ...
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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% 1. 0.1μ RHYST 121k 280k REF RBIAS R1 93.1k 93. RNTC* PG 470k ...
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... ON THE TOP AND BOTTOM OF PACKAGE UE/DE Package 12-Lead Plastic DFN (4mm × 3mm) (Reference LTC DWG # 05-08-1695) 0.70 0.05 3.30 0.05 PACKAGE OUTLINE 0.50 BSC 2.50 REF 4.00 0.10 (2 SIDES 0.05 TYP 3.00 0.10 (2 SIDES) 0.75 0.05 BOTTOM VIEW—EXPOSED PAD 0.00 – 0.05 LTC2938/LTC2939 0.40 0. 0.115 TYP 7 12 3.30 0.10 1.70 0.10 PIN 1 NOTCH R = 0.20 OR 0.35 45 CHAMFER 6 1 (UE12/DE12) DFN 0806 REV D 0.25 0.05 0.50 BSC 2.50 REF ...
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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 GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") PER SIDE 4. DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.152mm (.006" ...
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... DETAIL “A” MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LTC2938/LTC2939 (NOTE 3) 0.280 0.076 (.011 .003) 9 REF 3.00 0.102 (.118 .004) (NOTE 4) 0.86 (.034) REF 0.1016 0.0508 (.004 .002) MSOP (MS16) 1107 REV Ø ...
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... Confi gurable 6-Supply Monitor with Individual Comparator Outputs Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 5V 3.3V 1μ CRT V REF LTC2938 R1 RST 9.53k 1% WDO V PG WDI GND 47nF 93.1k 1% CWT COMMENTS Adjustable Reset, 10-Lead MSOP and DFN Packages ...