LTC1235CS Linear Technology, LTC1235CS Datasheet
LTC1235CS
Specifications of LTC1235CS
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LTC1235CS Summary of contents
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... Backup and External Reset Control APPLICATIONS n Critical μP Power Monitoring n Intelligent Instruments n Battery-Powered Computers and Controllers n Automotive Systems L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION LT1086-5 V ≥ 7. ...
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... Storage Temperature Range ................... –65°C to 150°C Lead Temperature (Soldering, 10 sec.) ................. 300°C RESET 16 RESET 15 WDO OUT 12 11 WDI PFO 10 9 PFI PART MARKING PACKAGE DESCRIPTION LTC1235CN 16-Lead Plastic DIP LTC1235CSW 16-Lead Plastic SOL http://www.linear.com/leadfree/ http://www.linear.com/tapeandreel/ BATTERY POWER FAIL TIMER BACKUP WARNING ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are 25°C, unless otherwise noted. A PARAMETER Battery Backup Switching Operating Voltage Range BATT V Output Voltage OUT BACKUP Input Threshold BACKUP Pullup Current (Note 4) ...
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LTC1235 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are 25°C, unless otherwise noted. A PARAMETER RESET, RESET, WDO, LOW LINE Output Short Circuit Current (Note 6) WDI Input Threshold WDI Input Current Power Fail Detector PFI ...
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TYPICAL PERFORMANCE CHARACTERISTICS OUT OUT 5. 2.8V BATT ° 4. 4.90 SLOPE = 5Ω 4.85 4.80 4. LOAD CURRENT (mA) 1235 ...
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LTC1235 PIN FUNCTIONS V (Pin 1): Backup battery input. When V BATT V , the status of the BACKUP pin stored in the Memory BATT Logic controls M2. If the status is high, auxiliary power, connected delivered ...
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PIN FUNCTIONS high when ever there is a transition on the WDI pin, or LOW LINE goes low. The watchdog timer can be disabled by fl oating WDI (see Figure 11). RESET (Pin 15): Logic output for μP reset control. ...
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LTC1235 APPLICATIONS INFORMATION Power Monitoring The LTC1235 uses a bandgap voltage reference and a precision voltage comparator C1 to monitor the 5V supply input on V (see Block Diagram). When V CC the reset voltage threshold, the reset outputs are ...
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APPLICATIONS INFORMATION Voltage Output During normal operation, the LTC1235 uses a charge pumped NMOS power switch to achieve low dropout and low supply current. This power switch can deliver up to 50mA to V from V and has a typical ...
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LTC1235 APPLICATIONS INFORMATION V IN BATTERY SAVING MODE OUT BACKUP LOGIC LOW RESET VOLTAGE THRESHOLD BATT V OUT Hi BATTERY BACKUP MODE OUT LOGIC BACKUP HIGH RESET VOLTAGE THRESHOLD BATT V OUT ...
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Table 1 shows the state of each pin during battery backup. If the backup battery is not used, connect V and OUT CC Table 1. Input and Output Status in Battery Backup Mode SIGNAL STATUS V ...
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LTC1235 APPLICATIONS INFORMATION Power Fail Warning The LTC1235 generates a Power Failure Output (PFO) for early warning of failure in the microprocessor’s power sup- ply. This is accomplished by comparing the Power Failure Input (PFI) with an internal 1.3V reference. ...
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APPLICATIONS INFORMATION The 10.7ms allows enough time to execute shut-down procedure for microprocessor and 831mV of hysteresis would prevent PFO from going low due to the noise of V Example 2: The circuit in Figure 9 can be used to ...
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LTC1235 TYPICAL APPLICATIONS R1 10k R2 30k +5V 0.1μF +3V 14 Capacitor Backup with 74HC4016 Switch + OUT 0.1μ LTC1235 LOW LINE 74HC4016 BATT GND 100μF Write ...
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... MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED .006" (0.15mm) 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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... UL recognized and conditional battery backup, RAM protect UL recognized battery backup UL recognized and conditional battery backup, RAM protect UL recognized battery backup UL recognized and conditional battery backup, RAM protect Microprocessor Supervisory Circuit www.linear.com ● 1235fa LT 0708 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 1992 ...