LTC2938/LTC2939 Con gurable 4- and 6-Supply Monitors with Watchdog Timer FEATURES DESCRIPTION n Simultaneously Monitors Four (LTC2938) or Six The LTC 2938/LTC2939 are con gurable supply monitors Supplies (LTC2939) for systems with up to four or six supply voltages that need n Sixteen User-Selectable Combinations of 5V, 3.3V, watchdog supervision. One of sixteen preset or adjustable 2.5V, 1.8V, 1.5V, 1.2V and/or Adjustable Voltage voltage monitor combinations can be selected using an Thresholds external resistive divider connected to the program input. n Guaranteed Threshold Accuracy: 1.5% The preset voltage thresholds are accurate to 1.5% over n Adjustable Reset and Watchdog Timeout temperature. The LTC2938 and LTC2939 also feature ad- n Low Supply Current: 80A Typical justable inputs with a 0.5V nominal threshold. n Power Supply Glitch Immunity The reset and watchdog timeout periods are adjustable n Guaranteed RST for V > 1V CC using external capacitors. Tight voltage threshold accuracy n High Temperature Operation to 125C and glitch immunity ensure reliable reset operation without n 12-Pin 4mm 3mm DFN or 12-Lead MSOP false triggering. The RST output is guaranteed to be in the (LTC2938) and 16-Lead MSOP Package (LTC2939) correct state for V down to 1V. Each status output has CC a weak internal pull-up and may be externally pulled up APPLICATIONS to a user-de ned voltage. n Desktop and Notebook Computers The 80A supply current makes the LTC2938 and LTC2939 n Multivoltage Systems ideal for power conscious systems. The LTC2939 moni- n Telecom Equipment tors up to six supplies and the LTC2938 monitors up to n Network Servers four supplies. n Automotive Control Systems 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. TYPICAL APPLICATION 6-Supply Monitor 12V (ADJ), 5V, 3.3V, 2.5V, 1.8V, 1.2V (ADJ) Voltage Con guration Table 12V V1 (V) V2 (V) V3 (V) V4 (V) V5 (V) V6 (V) 5V 5 3.3 2.5 1.8 ADJ ADJ 3.3V SYSTEM 2.5V 5 3.3 2.5 ADJ ADJ ADJ LOGIC 1.8V 5 3.3 1.8 ADJ ADJ ADJ 1.2V 5 3.3 ADJ ADJ ADJ ADJ 2150k 124k 5 3.3 ADJ ADJ ADJ ADJ 1% 1% 3.3 2.5 1.8 1.5 ADJ ADJ V1 V2 3.3 2.5 1.8 ADJ ADJ ADJ V3 3.3 1.8 1.5 1.2 ADJ ADJ V4 WDI 0.1F V5 3.3 1.8 1.5 ADJ ADJ ADJ LTC2939 V6 WDO 0.1F 3.3 1.8 1.2 ADJ ADJ ADJ V REF 100k 100k RST R1 3.3 2.5 ADJ ADJ ADJ ADJ 1% 1% 59k 3.3 2.5 ADJ ADJ ADJ ADJ 1% V PG t = 94ms RST 3.3 1.8 ADJ ADJ ADJ ADJ GND CWT CRT t = 940ms WD R2 3.3 1.8 ADJ ADJ ADJ ADJ C C 40.2k WT RT 3.3 1.5 ADJ ADJ ADJ ADJ 47nF 47nF 1% 293839 TA01 3.3 1.2 ADJ ADJ ADJ ADJ 293839ff 1LTC2938/LTC2939 ABSOLUTE MAXIMUM RATINGS (Notes 1, 2, 3) V1, V2, V3, V4, V5, V6, V ......................... 0.3V to 7V Operating Temperature Range PG RST .............................................................. 0.3V to 7V LTC2939C ..................................................... 0C to 70C CWT, WDO .................................................... 0.3V to 7V LTC2939I .................................................. 40C to 85C CRT, V , WDI ..............................0.3V to (V + 0.3V) LTC2939H .............................................. 40C to 125C REF CC Reference Load Current (I ) .............................. 1mA Storage Temperature Range ................... 65C to 150C VREF V4 Input Current (ADJ Mode) ..............................1mA Lead Temperature (Soldering 10 sec) RST, WDO Currents ............................................10mA MS Package Only .............................................. 300C PIN CONFIGURATION LTC2938 LTC2938 LTC2939 TOP VIEW V3 1 12 V2 TOP VIEW TOP VIEW V5 1 16 V6 V1 2 11 V4 V3 1 12 V2 V3 2 15 V2 V1 2 11 V4 CRT 3 10 V V1 3 14 V4 REF 13 CRT 3 10 V NC 4 13 NC REF RST 4 9 V PG 4 CRT 5 12 V RST 9 V REF PG RST 6 11 V 5 PG WDO 8 GND WDO 5 8 GND WDO 7 10 GND 6 7 CWT WDI WDI 8 9 CWT WDI 6 7 CWT MS PACKAGE MS PACKAGE 12-LEAD PLASTIC MSOP 16-LEAD PLASTIC MSOP DE PACKAGE 12-LEAD (4mm s 3mm) PLASTIC DFN T = 125C, = 130C/W T = 125C, = 110C/W JMAX JA JMAX JA T = 125C, = 43C/W JMAX JA EXPOSED PAD (PIN 13) PCB GND CONNECTION OPTIONAL ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE LTC2938CDE PBF LTC2938CDE TRPBF 2938 0C to 70C 12-Lead (4mm 3mm) Plastic DFN LTC2938IDE PBF LTC2938IDE TRPBF 2938 40C to 85C 12-Lead (4mm 3mm) Plastic DFN LTC2938HDE PBF LTC2938HDE TRPBF 2938 12-Lead (4mm 3mm) Plastic DFN 40C to 125C LTC2938CMS PBF LTC2938CMS TRPBF 2938 12-Lead Plastic MSOP 0C to 70C LTC2938IMS PBF LTC2938IMS TRPBF 2938 12-Lead Plastic MSOP 40C to 85C LTC2938HMS PBF LTC2938HMS TRPBF 2938 12-Lead Plastic MSOP 40C to 125C LTC2939CMS PBF LTC2939CMS TRPBF 2939 16-Lead Plastic MSOP 0C to 70C LTC2939IMS PBF LTC2939IMS TRPBF 2939 16-Lead Plastic MSOP 40C to 85C LTC2939HMS PBF LTC2939HMS TRPBF 2939 16-Lead Plastic MSOP 40C to 125C Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container. 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