LTC2928 Multichannel Power Supply Sequencer and Supervisor FEATURES DESCRIPTION n Easily Configure Power Management The LTC 2928 is a four channel cascadable power without Software supply sequencer and high accuracy supervisor. Sequenc- n Controls Up to Four Supplies per Device ing thresholds, order and timing are configured with just a n Cascades for Additional Supplies few external components, negating the need for PC board n layout or software changes during system development. Staged Supply Sequencing with Multiple LTC2928s may be easily connected to sequence Adjustable Time Positions n an unlimited number of power supplies. Fault Event Reporting with Diagnostics n Selectable System Shutdown on Fault Sequence outputs control supply enable pins or n 1.5% Undervoltage Monitor Accuracy N-channel pass gates. Precision input comparators with n Overvoltage and/or Fault Indication individual outputs monitor power supply voltages to 1.5% n Configurable Undervoltage and accuracy. Supervisory functions include undervoltage Overvoltage Thresholds and overvoltage monitoring and reporting as well as P n Charge Pumped Enable Pins Drive N-Channel MOSFETs reset generation. RST may be forced high to complement n Operates from 2.9V to 16.5V margin testing. n 5mm 7mm 38-lead QFN and Application faults, whether internally or externally gener- 36-lead SSOP Packages ated, can shut down all controlled supplies. The type and source of faults are reported for diagnosis. Individual APPLICATIONS channel controls are available to independently exercise n Network/Telecom Infrastructure enable outputs and supervisory functions. n Sequencing for Multiple I/O and Core Voltages A high voltage input allows the LTC2928 to be powered n Power Management from voltages as high as 16.5V. A buffered reference All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 4843302, 6949965. output permits single negative power supply sequencing and monitoring operations. TYPICAL APPLICATION Sequencing Up and Down LTM4600 3.3V 12V V V IN OUT RUN 3.3V LTC3414 10k V V 1.2V IN OUT 2.5V RUN 1.8V LTC1628 1.2V 2.5V V V IN OUT RUN AUSTIN LYNX Si7894ADP 1V/DIV V V IN OUT 1.8V ON AXA010AY93 100 12.1k 36.5k 0.1F 23.2k 51.1k HV EN2 EN1 EN4 EN3 CC ON ON V1 95.3k RT1 V2 24.3k DONE RT2 V3 9.53k LTC2928 RT3 V4 SYSTEM 1.5k RT4 RST RESET 3.4k DONE OV START SEQUENCE V FLT FAULT CC SEQUENCE DOWN SEQUENCE UP START GND MS1 VSEL RTMR PTMR STMR 1F UP COMPLETE 10k 10k 10k 10k COMPLETE SEQUENCE 0.047F 3300pF DOWN 2928 TA07 ALL RESISTORS 1% 2928 TA06 Rev. B 1 Document Feedback For more information www.analog.comLTC2928 ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltages FLT, RST, OV, CAS ................................ 0.3V to 6.5V HV ...................................................... 0.3V to 18V DONE, REF ...................................0.3V to V + 0.3V CC CC V ........................................................ 0.3V to 6.5V RMS Currents CC Input Voltages IV ................................................................. 10mA CC V1, V2, V3, V4 .........................................0.3V to 12V IHV .............................................................. 20mA CC MS1, MS2, RDIS ................................... 0.3V to 6.5V I .................................................................. 10mA REF SQT1, SQT2, VSEL ............................... 0.3V to 6.5V Operating Ambient Temperature Range RT1, RT2, RT3, RT4 .............................. 0.3V to 6.5V LTC2928C ................................................ 0C to 70C ON, OVA .........................................0.3 to V + 0.3V LTC2928I .............................................40C to 85C CC STMR, PTMR, RTMR .....................0.3 to V + 0.3V Storage Temperature Range CC Output Voltages SSOP Package ................................... 65C to 150C EN1, EN2, EN3, EN4 (Note 3) ..................0.3V to 12V QFN Package ..................................... 65C to 150C CMP1, CMP2, CMP3, CMP4.................. 0.3V to 6.5V Lead Temperature (Soldering, 10 sec) SSOP Package ..................................................300C PIN CONFIGURATION TOP VIEW TOP VIEW CMP1 1 36 CMP4 CMP2 2 35 CMP3 EN2 3 34 V3 38 37 36 35 34 33 32 V2 4 33 EN3 OVA 1 31 EN3 OVA 5 32 V4 EN1 2 30 V4 EN1 6 31 EN4 V1 3 29 EN4 N/C 4 28 RTMR V1 7 30 RTMR REF 5 27 PTMR REF 8 29 PTMR RT1 6 26 STMR RT1 9 28 STMR 39 RT2 7 25 VSEL RT2 10 27 VSEL RT3 8 24 GND RT3 11 26 GND RT4 9 23 HV CC RT4 12 25 HV CC SQT1 10 22 V CC SQT1 13 24 V CC 21 SQT2 11 RST SQT2 14 23 RST MS1 12 20 OV MS1 15 22 OV 13 14 15 16 17 18 19 MS2 16 21 FLT RDIS 17 20 DONE UHF PACKAGE CAS 18 19 ON 38-LEAD (5mm 7mm) PLASTIC QFN T = 125C, = 34C/W JMAX JA G PACKAGE EXPOSED PAD (PIN 39) PCB GND CONNECTION OPTIONAL 36-LEAD PLASTIC SSOP T = 125C, = 95C/W JMAX JA Rev. B 2 For more information www.analog.com MS2 V2 RDIS EN2 CAS CMP2 CMP1 ON N/C CMP4 DONE CMP3 FLT V3