ltc2978 Linear Technology Corporation, ltc2978 Datasheet
ltc2978
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ltc2978 Summary of contents
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... The 1-wire synchronization bus supports power supply sequencing across multiple LTC2978 devices. User pro- grammable parameters can be stored in EEPROM. Voltage supervisor, voltage monitor and temperature faults can also be logged to EEPROM ...
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... LTC2978 Table oF conTenTs Features .............................................................................................................................1 Applications ........................................................................................................................1 Typical Application ................................................................................................................1 Description..........................................................................................................................1 Absolute Maximum Ratings ......................................................................................................3 Order Information ..................................................................................................................3 Pin Configuration ..................................................................................................................3 Electrical Characteristics .........................................................................................................4 Timing Diagram ....................................................................................................................8 Typical Performance Characteristics ...........................................................................................8 Pin Functions ..................................................................................................................... 12 Block Diagram .................................................................................................................... 14 Operation.......................................................................................................................... 15 Operation Overview ...............................................................................................................................................15 PMBus Serial Digital Interface ...............................................................................................................................16 Register Command Set ..........................................................................................................................................18 Detailed PMBus Command Register Descriptions .................................................................................................22 Manufacturer Specific Commands ...
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... GND ................................. –0. OUT_EN[7: GND .................................... –0. DACP[7: GND ............................... –0.3V to 0.3V DACM[7:0] Operating Temperature Range: LTC2978C ................................................ 0°C to 70°C LTC2978I .............................................–40°C to 85°C Storage Temperature Range .................. –65°C to 125°C orDer inForMaTion LEAD FREE FINISH TAPE AND REEL LTC2978CUP#PBF LTC2978CUP#TRPBF LTC2978IUP#PBF LTC2978IUP#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges ...
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... LTC2978 elecTrical characTerisTics temperature range, otherwise specifications are at T otherwise indicated 100nF , C VDD33 VDD25 SYMBOL PARAMETER Power-Supply Characteristics V V Supply Input Operating Range PWR PWR I V Supply Current PWR PWR I V Supply Current VDD33 DD33 V V Undervoltage Lockout UVLO_VDD33 DD33 V Undervoltage Lockout ...
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... High Resolution Mode IN_VS 0.8V ≤ V ≤ 1.5V, High Resolution Mode IN_VS 3V ≤ V ≤ 8V VIN_SNS V > 8V VIN_SNS 3V ≤ V ≤ 8V VIN_SNS V > 8V VIN_SNS I = –5µ 3.3V VOUT_ENn DD33 LTC2978 , V and REF pins floating, unless DD33 DD25 MIN TYP MAX ±0 250 1.32 1.38 1.44 l 2.53 2 ...
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... LTC2978 elecTrical characTerisTics temperature range, otherwise specifications are at T otherwise indicated 100nF , C VDD33 VDD25 SYMBOL PARAMETER I Output Sourcing Current VOUT_ENn Output Sinking Current Output Leakage Current V Enable Output (V [7:4]) Characteristics OUT OUT_EN I Output Sinking Current VOUT_ENn Output Leakage Current V Enable Output (V ) Characteristics ...
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... The minimum retention specification applies for devices whose EEPROM has been cycled less than the minimum endurance specification. Note 9: The LTC2978 will not acknowledge any PMBus write commands when a STORE_USER_ALL command is being executed. Note 10: Maximum capacitive load, C and clock rise time (t 300ns and (20 + 0.1 • ...
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... LTC2978 TiMing DiagraM SDA LOW SCL t HD(STA) t HD(DAT) START CONDITION Typical perForMance characTerisTics Reference Voltage vs Temperature 1.2355 1.2350 1.2345 1.2340 1.2335 1.2330 1.2325 1.2320 1.2315 THREE TYPICAL PARTS 1.2310 –50 –35 –20 – TEMPERATURE (°C) 2978 G01 ...
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... Differential Input Current 100 120 140 160 DIFFERENTIAL INPUT VOLTAGE (mV) LTC2978 ADC Rejection vs Frequency at V (Current Sense Mode –20 –40 –60 –80 –100 –120 12500 0 12500 25000 37500 FREQUENCY (Hz) 2978 G08 Voltage Supervisor Total ...
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... LTC2978 Typical perForMance characTerisTics Voltage Buffered IDAC Offset Voltage vs Temperature 2.5 2.3 2.1 1.9 1.7 1.5 1.3 1.1 0.9 0.7 0.5 –50 –35 – – TEMPERATURE (°C) 2978 G16 Voltage Buffered IDAC Load Regulation (Sourcing) 2.698 85°C 2.696 2.694 25°C 2.692 2.690 2.688 2.686 2.684 2.682 –40°C 2.680 2 ...
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... V and V V OUT_EN[3:0] IN_EN OL vs Current 1.4 1.2 1.0 85°C 0.8 25°C 0.6 –40°C 0.4 0 (mA) SINK LTC2978 V Regulator Short-Circuit DD33 Current vs Temperature –86 –88 –90 –92 –94 –96 –98 –100 –102 –50 –35 –20 – 13.5 15 TEMPERATURE (°C) 2978 G26 V and V ...
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... LTC2978 Typical perForMance characTerisTics PWRGD and FAULTBzn V vs Current 1.2 1.0 0.8 0.6 0.4 0 (mA) SINK pin FuncTions PIN NAME PIN NUMBER PIN TYPE SENSEM6 SENSEP7 SENSEM7 V 4 Out OUT_EN0 V 5 Out OUT_EN1 V 6 Out OUT_EN2 V 7 Out OUT_EN3 V 8 Out ...
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... DC/DC Converter Differential (+) Output Voltage or Current-5 Sensing Pins DC/DC Converter Differential (–) Output Voltage or Current-5 Sensing Pins DC/DC Converter Differential (+) Output Voltage-6 Sensing Pin Exposed Pad, Must be Soldered to PCB LTC2978 , GND or Float to Encode Logic States DD33 , GND or Float to Encode Logic States DD33 ...
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... LTC2978 block DiagraM 3.3V REGULATOR PWR IN OUT DD33 2.5V REGULATOR DD33 IN V OUT V 18 DD25 3R V SENSEM0 V 14 IN_SNS V SENSEP0 R V SENSEM1 V SENSEP1 GND 65 V SENSEM2 V SENSEP2 V SENSEM3 V SENSEP3 V SENSEM4 INTERNAL V SENSEP4 TEMP MUX SENSOR V SENSEM5 V SENSEP5 V SENSEM6 ...
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... OPERATION OVERVIEW The LTC2978 is a PMBus programmable power supply controller, monitor, sequencer and voltage supervisor that can perform the following operations: Accept PMBus compatible programming commands. n Provide DC/DC converter input voltage and output volt- n age/current read back through the PMBus interface. ...
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... ALL, MFR_CONFIG or if fault log data is being written to the EEPROM. Status_word_busy will also be set. Slave Address The LTC2978 can be configured to respond to one of nine addresses for a given MFR_I2C_BASE_ADDRESS value (the factory default value for this register is 7’h5C). In addition, the LTC2978 will always respond to its global address and the PMBus Alert Response address regard- less of the state of the address select pins ...
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... Wr A COMMAND CODE A S SLAVE ADDRESS Figure 9. Read Byte Protocol COMMAND CODE A S SLAVE ADDRESS Rd A Figure 10. Read Byte Protocol with PEC LTC2978 2978 F01 DATA BYTE HIGH A P 2978 F02 ...
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... LTC2978 operaTion REGISTER COMMAND SET Summary COMMAND FUNCTION DESCRIPTION PAGE OPERATION Operating mode control. ON_OFF_CONFIG CONTROL pin and PMBus bus on/off command setting. CLEAR_FAULTS CLEAR_FAULTS is used to clear any fault bits that have been set. WRITE_PROTECT Provides protection against accidental changes. STORE_USER_ALL Store entire operating memory to EEPROM ...
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... TON_DELAY Time, in ms, from CONTROL and/or Operation TON_RISE Time, in ms, from when the output starts to rise until the LTC2978 optionally soft- connects its voltage-buffered current DAC and begins to servo the output voltage to the desired value. TON_MAX_FAULT_LIMIT Maximum time, in ms, from V ...
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... LTC2978 operaTion Summary COMMAND FUNCTION DESCRIPTION TOFF_DELAY Time, in ms, from CONTROL and/or Operation off to VOUT_EN off. STATUS_BYTE Fault status reporting. STATUS_WORD The STATUS_WORD command returns two bytes of information with a summary of the unit’s fault condition. STATUS_VOUT Voltage fault status reporting. STATUS_INPUT ...
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... Returns values detected and driven onto digital I/O pads. MFR_I2C_BASE_ADDRESS This register determines the base value of the I MFR_SPECIAL_ID This register contains the manufacturer code for identifying the LTC2978. MFR_SPECIAL_LOT These registers contain customer dependent codes that identify the factory programmed user configuration stored in EEPROM. MFR_VOUT_DISCHARGE_THRESHOLD ...
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... LTC2978 operaTion Summary COMMAND FUNCTION DESCRIPTION MFR_COMMON Contains manufacturer status bits that are common across multiple LTC chips. MFR_SPARE_0 Scratchpad register. MFR_SPARE_2 Paged scratchpad register. MFR_VOUT_MIN Returns the minimum measured value of VOUT. MFR_VIN_MIN Returns the minimum measured value of V IN_SNS MFR_TEMPERATURE_MIN Returns the minimum measured junction temperature value ...
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... All remaining combinations Operation_control[1:0] Operation_margin[1:0] b[7:6] b[5: All remaining combinations LTC2978 Operation_fault[1:0] Reserved (read only) b[3:2] b[1: ...
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... ON_OFF_CONFIG The ON_OFF_CONFIG command configures the combina- tion of CONTROLn pin input and PMBus bus commands needed to turn the LTC2978 on/off, including the power-on behavior, as shown in the following table. This command register responds to the global page command. ON_OFF_CONFIG Data Contents BITS(S) SYMBOL ...
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... EEPROM may not be compatible with the values initially stored in operating memory. CAPABILITY The CAPABILITY command provides a way for a host system to determine some key capabilities of the LTC2978. This one byte command is read only. CAPABILITY Data Contents BITS(S) SYMBOL OPERATION ...
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... The three bit format specifies PMBus linear mode for all output voltage related commands. The five bit exponent provides the exponent for the mantissa specified in the data word. The LTC2978 device sets the format at the time of manufacture. The five bit exponent is read only and is set to a value of –13 decimal. ...
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... This delay is counted using SHARE_CLK only. TON_RISE is the amount of time in ms that elapses after the power supply has been enabled until the LTC2978’s voltage buffered current DAC soft connects and servo’s the output voltage to the desired level if Mfr_dac_mode = 2’ ...
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... The fault response documented here is for voltages that are measured by the high speed supervisor. These voltages are measured over a short period of time and may require a de-glitch period. Note that in addition to the response described by these commands, the LTC2978 will also: Data Contents BIT(S) SYMBOL OPERATION b[7:6] Vout_ov_fault_response_action, Response action ...
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... The fault response documented here is for values that are measured by the ADC. These values are measured over a longer period of time and are not de-glitched. Note that in addition to the response described by these commands, the LTC2978 will also: Data Contents BIT(S) SYMBOL OPERATION ...
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... LTC2978 operaTion Timed Fault Response TON_MAX_FAULT_RESPONSE This command defines the LTC2978 response to a TON_MAX_FAULT. At start-up, the TON_MAX_FAULT_ RESPONSE is disarmed once the output voltage reaches the VOUT_UNDER_VOLTAGE_LIMIT. The only way to protect against a short-circuited output at start- take action in response to a TON_MAX_FAULT since VOUT_UV_FAULT_RESPONSE is not armed until the output reaches the VOUT_UNDER_VOLTAGE_LIMIT ...
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... Not supported. Always returns 0. b[8] Status_word_unknown Not supported. Always returns 0. b[7] Status_word_busy Device busy when PMBus command received. b[6] Status_word_off Status_byte_off b[5] Status_word_vout_ov Status_byte_vout_ov b[4] Status_word_iout_oc Not supported. Always returns 0. b[3] Status_word_vin_uv Status_byte_vin_uv b[2] Status_word_temp Status_byte_temp b[1] Status_word_cml Status_byte_cml b[0] Status_word_high_byte A bit in the high byte of the STATUS_WORD (b[15:8]) is set. LTC2978 2978fa ...
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... LTC2978 operaTion STATUS_VOUT The STATUS_VOUT command returns the summary of the voltage faults or warnings which have occurred, as shown in the following table: STATUS_VOUT Data Contents BIT(S) SYMBOL OPERATION b[7] Status_vout_ov_fault Overvoltage fault. b[6] Status_vout_ov_warn Overvoltage warning. b[5] Status_vout_uv_warn Undervoltage warning b[4] Status_vout_uv_fault Undervoltage fault. b[3] Status_vout_max_fault VOUT_MAX fault. An attempt ...
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... DACP A previous servo operation terminated with maximum or minimum DAC value. V has been deasserted due to a VOUT fault. IN_EN watchdog fault has occurred watchdog fault has occurred. LTC2978 CHANNEL FAULT Current Page Yes Current Page Yes Current Page Yes ...
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... LTC2978’s internal temperature sensor. pin. IN_SNS READ_TEMPERATURE_1 Data Contents BIT(S) SYMBOL b[15:0] Read_temperature_1 [15:0] The data uses the linear format: N PMBUS_REVISION The PMBUS_REVISION command register is read only and reports the LTC2978 compliance to the PMBus standard revision 1.1. PMBUS_REVISION Data Contents BIT(S) SYMBOL b[7:0] PMBus_rev N where Y = b[15: OPERATION N Temp(Symbol • ...
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... Select DAC buffer gain dac_gain_0 (1.38V full-scale) 1: Select DAC buffer gain dac_gain_1 (2.65V full-scale) DAC output polarity. 0: Encodes negative (inverting) DC/DC converter trim input. 1: Encodes positive (noninverting) DC/DC converter trim input. LTC2978 3.8V 6.0V. after it has reached a new margin or nominal OUT warning threshold is met or exceeded. ...
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... LTC2978 operaTion MFR_CONFIG_ALL: This command is used to configure parameters that are common to all channels on the IC. They may be set or reviewed from any PAGE setting. MFR_CONFIG_ALL Data Contents BIT(S) SYMBOL OPERATION b[7] Mfr_config_fault_log_enable Enable fault logging to NVM in response to Fault. 0: Fault logging to NVM is disabled 1: Fault logging to NVM is ...
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... MFR_FAULTB11_PROPAGATE These manufacturer specific commands enable channels that have faulted off to propagate that state to the ap- propriate fault pin. There are two zones in the LTC2978. In zone 0, faulted off states for channels 0 through 3 can be propagated to FAULT00 or FAULT01. In zone 1, faulted off states for channels 4 through 7 can be propagated to FAULT10 or FAULT11. See Figure 13. MFR_FAULTB00_PROPAGATE Data Contents— ...
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... LTC2978 operaTion MFR_PWRGD_EN This command register controls the mapping of power good status to the power good pin. Note that odd num- bered channels whose ADC is in high res mode do not contribute to power good. MFR_PWRGD_EN Data Contents BIT(S) SYMBOL OPERATION b[15:9] Reserved Read only, always returns 0s. ...
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... FAULTB10 pin is asserted, and MFR_FAULTB11_RESPONSE determines how channels 4-7 respond when the FAULTB11 pin is asserted. If one or more bits in the MFR_FAULTBzn_RESPONSE registers are set, a FAULTBzn assertion will cause the ALERTB pin to assert low and set the appropriate bit in the STATUS_MFR_ SPECIFIC register. LTC2978 2978fa ...
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... LTC2978 operaTion MFR_VINEN_OV_FAULT_RESPONSE This command register determines whether V voltage faults from a given channel cause the forced off. MFR_VINEN_OV_FAULT_RESPONSE Data Contents BIT(S) SYMBOL b[7] Mfr_vinen_ov_fault_response_chan7 b[6] Mfr_vinen_ov_fault_response_chan6 b[5] Mfr_vinen_ov_fault_response_chan5 b[4] Mfr_vinen_ov_fault_response_chan4 b[3] Mfr_vinen_ov_fault_response_chan3 b[2] Mfr_vinen_ov_fault_response_chan2 b[1] Mfr_vinen_ov_fault_response_chan1 b[0] Mfr_vinen_ov_fault_response_chan0 0 over OUT pin IN_EN OPERATION Response to channel 7 VOUT_OV_FAULT Disable V via fast pull-down. ...
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... Response to channel 3 VOUT_UV_FAULT Disable V via fast pull-down. IN_EN 0 = Leave V as-is. IN_EN Response to channel 2 VOUT_UV_FAULT Disable V via fast pull-down. IN_EN 0 = Leave V as-is. IN_EN Response to channel 1 VOUT_UV_FAULT Disable V via fast pull-down. IN_EN 0 = Leave V as-is. IN_EN Response to channel 0 VOUT_UV_FAULT Disable V via fast pull-down. IN_EN 0 = Leave V as-is. IN_EN LTC2978 2978fa ...
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... LTC2978 operaTion MFR_RETRY_DELAY This command determines the retry interval when the LTC2978 is in hiccup mode in response to a fault condition. MFR_RETRY_DELAY Data Contents BIT(S) SYMBOL OPERATION b[15:0] Mfr_retry_delay The data uses the linear format: T(Symbol • 2 Where N = b[15:11 5-bit two’s complement integer and Y = b[10: 11-bit two’ ...
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... LTC2978 emerges from power-on reset or when a CLEAR_FAULTS command is executed. MFR_TEMPERATURE_PEAK Data Contents BIT(S) SYMBOL OPERATION b[15:0] Mfr_temperature_peak[15:0] The data uses the linear format: V(Symbol • 2 Where N = b[15:11 5-bit two’s complement integer and Y = b[10: 11-bit two’s complement integer Units: ° ...
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... Reserved Read only, always returns 0. b[6:0] i2c_base_address This 7-bit value determines the base value 2 of the 7-bit I C address. MFR_SPECIAL_ID This register contains the manufacturer ID for the LTC2978. MFR_SPECIAL_ID Data Contents BIT(S) SYMBOL OPERATION b[15:0] Mfr_special_id Read only, always returns ‘h0121 MFR_SPECIAL_LOT These paged registers contain information that identifies the user configuration that was programmed at the factory ...
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... MFR_FAULT_LOG command. This bit is cleared by a MFR_FAULT_LOG command. MFR_FAULT_LOG_STATUS Data Contents N BIT(S) SYMBOL b[1] Mfr_fault_log_status_ram b[0] Mfr_fault_log_status_eeprom Fault log EEPROM status: LTC2978 OPERATION Fault log RAM status: 0: The fault log RAM allows updates. 1: The fault log RAM is locked until the next Mfr_fault_log read. 0: The transfer of the fault log RAM to the EEPROM is enabled ...
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... Mfr_fault_log_status_eeprom is set high after the RAM buffer is transferred to EEPROM and not cleared until a Mfr_fault_log_clear is received; even if the LTC2978 is reset or powered down. Fault log EEPROM transfers are not initiated as a result of Status_mfr_dis- charge, Status_mfr_fault1_in or Status_mfr_fault0_in events. During a Mfr_fault_log read, data is returned one byte at a time as defined by the following table ...
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... EEPROM using the STORE_USER_ALL and RESTORE_USER_ALL com- mands, respectively. MFR_SPARE2 These 16-bit wide, paged registers can be used to store miscellaneous information. The contents of these reg- isters may be stored and recalled from EEPROM using the STORE_USER_ALL and RESTORE_USER_ALL com- mands, respectively. LTC2978 2978fa ...
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... MFR_VOUT_MIN This command returns the minimum ADC measured value of the channel’s output voltage. The contents of this reg- ister is reset to ‘hFFFF when the LTC2978 emerges from power-on reset or when a CLEAR_FAULTS command is executed. When odd channels are configured to measure current, this command is not supported. ...
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... EEPROM. WRITE-PROTECT PIN The WP pin allows the user to write-protect the LTC2978’s configuration registers. The WP pin is active high, and when asserted it overrides the WRITE_PROTECT com- mand register. All registers are write-protected by the WP pin except for PAGE, OPERATION, CLEAR_FAULTS, MFR_PAGE_FF_MASK and STORE_USER_ALL ...
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... Setting Command Register Values The command register settings described herein are for the purpose of understanding and software development in a host processor. In actual practice, the LTC2978 can be completely configured for standalone operation with the LTC DC590B dongle and software GUI using intuitive menu driven objects ...
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... DC/DC converter, or allowing the DC/DC converter to continue operating in spite of the fault DC/DC converter is disabled, the LTC2978 can be configured to retry or latch-off. The retry interval is specified using the MFR_RETRY_DELAY command. Latched faults are reset by toggling the CONTROLn pin, using the OPERATION ...
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... V pin to assert low in response to VOUT_OV/UV IN_EN fault conditions. The V output will stop pulling low IN_EN when the LTC2978 is commanded to re-enter the ON state following a faulted-off condition. A charge-pumped 5µA pull-up to 12V is also available on the V output. Refer to the MFR_CONFIG_ALL IN_EN register description in the OPERATION section for more information ...
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... PAGE = 4 MFR_FAULTB10_PROPAGATE, PAGE = 5 CHANNEL 5 MFR_FAULTB11_PROPAGATE, PAGE = 5 EVENT PROCESSOR PAGE = 5 MFR_FAULTB10_PROPAGATE, PAGE = 6 CHANNEL 6 MFR_FAULTB11_PROPAGATE, PAGE = 6 EVENT PROCESSOR PAGE = 6 MFR_FAULTB10_PROPAGATE, PAGE = 7 CHANNEL 7 MFR_FAULTB11_PROPAGATE, PAGE = 7 EVENT PROCESSOR PAGE = 7 Figure 13. Channel Fault Management Block Diagram LTC2978 FAULTB00 FAULTB01 ZONE 0 ZONE 1 FAULTB10 FAULTB11 2978 F13 2978fa ...
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... ALERTB is typically one line in an array of PMBus converters. The LTC2978 allows a rich combination of faults and warnings to be propagated to the ALERTB pin. • WDI/RESET can be used to put the LTC2978 in the sensed. IN power-on reset state. Pull WDI/RESET low for at least t RESETB • ...
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... V V DD33 SENSEP0 V DD33 LTC2978* V LOAD DD25 V DACM0 V SENSEM0 V OUT_EN0 GND *SOME DETAILS OMITTED FOR CLARITY ONLY ONE OF EIGHT CHANNELS SHOWN LTC2978 and V pins by the DACP0 DACM0 is Kelvin connected DACM0 DACP0 • • • 2978 F15 OUT R30 DC/DC CONVERTER R20 ...
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... Assume values for feedback resistor R20 and the nominal DC/DC converter output voltage V for R10 the output voltage of the DC/DC converter DC0(NOM) when the LTC2978’s V pin high impedance DACP0 state. R10 is a function of R20, V DC0(NOM) the feedback node (V ) when the loop is in regulation, FB and the feedback node’ ...
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... Trimming and Margining DC/DC Converters with a TRIM Pin Figure 17 illustrates a typical application circuit for trim- ming/margining the output voltage of a DC/DC converter with a TRIM Pin. The LTC2978’s V DACPn the TRIM pin through resistor R30, and the V connected to the converter’s point-of-load ground. ...
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... Select R corner frequency is ≤1/10 the DC/DC converter switching frequency and ≤1/10 of the internal 62.5kHz clock of the LTC2978’s ∆Σ ADC. This will assure that the DC value at the (+) input to the ADC will be equal to the output voltage with small ripple. Good values are R C ≥ ...
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... Antialiasing Filter Considerations Extremely noisy environments may require an antialiasing filter on the input to the LTC2978’s ADC. The R-C circuit shown in Figure 19 is adequate for most situations. Keep V IN 4.5V < V < 15V IBUS V 0.1µ 0.1µF R40 = R50 ≤ 200Ω to minimize ADC gain errors, and select a value for capacitors C10 and C20 that doesn’ ...
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... SYSTEM 3.3V LTC CONTROLLER HEADER Figure 20. LTC Controller Connections for Powering and Communicating with the LTC2978 0 the LTC2978’s and the I ered from the ORed 3.3V supply. In addition, any device sharing I have body diodes between the SDA/SCL pins and its V node because this will interfere with bus communication in the absence of system power ...
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... PC Board Layout Mechanical stress board and soldering-induced stress can cause the LTC2978’s reference voltage and voltage drift to shift. A simple way to reduce these stress- related shifts is to mount the IC near the short edge of the PC board corner. The board edge acts as a stress boundary region where the flexure of the board is minimal ...
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... OUT 47 R32 DC/DC CONVERTER R22 V LOAD FB 48 R12 46 RUN/SS SGND GND OUT 8 INTERMEDIATE BUS CONVERTER EN Figure 22. LTC2978 Application Circuit with 3.3V Chip Power 0.1µF 0.1µF 0.1µ DACP0 V SENSEP0 V SENSEM0 V DACM0 V OUT_EN0 V DACP1 V SENSEP1 V SENSEM1 V DACM1 ...
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... UP Package 64-Lead Plastic QFN (9mm × 9mm) (Reference LTC DWG # 05-08-1705 Rev C) 0.70 0.05 7.50 REF 8.10 0.05 9.50 0.05 (4 SIDES) PACKAGE OUTLINE 0.25 0.05 0.75 0. 0.10 TYP 7.50 REF (4-SIDES) 0.200 REF 0.00 – 0.05 LTC2978 R = 0.115 TYP 63 64 PIN 1 CHAMFER C = 0.35 7.15 0.10 7.15 0.10 (UP64) QFN 0406 REV C 0.25 0.05 0.50 BSC BOTTOM VIEW—EXPOSED PAD 0.40 0.10 1 ...
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... GATE 24.3k LTC4210 TIMER GND 10k 0.22µF 0.01µF 4.99k BAT54 Figure 23. LTC2978 Application Circuit with Crowbar Protection on Intermediate Bus relaTeD parTs PART NUMBER DESCRIPTION 2 LTC2970 Dual I C Power Supply Monitor and Margining Controller 2 LTC4151 High Voltage I C Current and Voltage Monitor LTC4210-3 Hot Swap™ ...