SFFS185 June   2021 LMR33620AP-Q1 , LMR33630AP-Q1

 

  1.   Trademarks
  2. 1Overview
  3. 2Failure Mode Distribution (FMD)
  4. 3Functional Safety Failure In Time (FIT) Rates
    1. 3.1 LMR33630AP-Q1
    2. 3.2 LMR33620AP-Q1
  5. 4Pin Failure Mode Analysis (Pin FMA)
    1. 4.1 LMR33630AP-Q1 and LMR33620AP-Q1

LMR33630AP-Q1 and LMR33620AP-Q1

Figure 4-1 shows the LMR33630AP-Q1 and LMR33620AP-Q1 pin diagram for the VQFN-12 package (RNX designator). For a detailed description of the device pins please refer to the 'Pin Configuration and Functions' section in the appropriate device datasheet.

GUID-9604561E-3AF4-4F98-A661-0687949FBA59-low.gifFigure 4-1 Pin Diagram
Table 4-2 Pin FMA for Device Pins Short-Circuited to Ground
Pin NamePin No.Description of Potential Failure Effect(s)Failure Effect Class
PGND1,11No effectD
VIN2,10Device will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device.A
N/C3No effect if this pin is not used by customer.D
When used to route the SW node to connect CBOOT (as recommended), damage to internal power FET(s) and/or other internal circuits.A
BOOT4Damage to internal circuitsA
VCC5Fault mode will shut device offB
AGND6No effectD
FB7The regulator will operate at maximum duty cycle. Output voltage will rise to nearly the input voltage (VIN) level. Possible damage to customer load and/or output stage components may occur. No effect on device.B
PG8Power good functionality will be lost.B
EN9Loss of ENABLE functionality Device will remain in shut-down mode.B
SW12Damage to internal power FET(s) and/or other internal circuitsA
Table 4-3 Pin FMA for Device Pins Open-Circuited
Pin NamePin No.Description of Potential Failure Effect(s)Failure Effect Class
PGND1,11With either one or both pins open, possible device damage.A
VIN2,10With both pins open: loss of output voltage. With one pin open: possible device damage.A
N/C3No effect if this pin is not used by customer.D
When used to route the SW node to connect CBOOT (as recommended), the effect is the same as "open on pin 4"B
BOOT4Loss of output voltage regulation; low or no output voltage.B
VCC5VCC LDO will be unstable. Loss of output voltage regulation and possible damage to internal circuits.A
AGND6Loss of output voltage regulation. Possible damage to internal circuits.A
FB7Loss of output voltage regulation. Output voltage may rise or fall outside of intended regulation window.B
PG8PG functionality will be lost.B
EN9Loss of ENABLE functionality. Erratic operation; probable loss of regulation.B
SW12Loss of output voltage.B
Table 4-4 Pin FMA for Device Pins Short-Circuited to Adjacent Pin
Pin NamePin No.Shorted toDescription of Potential Failure Effect(s)Failure Effect Class
PGND1VINDevice will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device.A
VIN2N/CNo effect if this pin is not used by customer.D
When used to route the SW node to connect CBOOT (as recommended), the output voltage will rise to nearly the level of VIN. Customer load will be damaged. Possible damage to deviceA
N/C3BOOTNo effect if this pin is not used by customer.D
When used to route the SW node to connect CBOOT (as recommended), damage to internal circuits. No output voltage will be produced.A
BOOT4VCCLoss of output regulation, possible damage to internal circuitsA
VCC5AGNDFault mode will shut device offB
AGND6FBThe regulator will operate at maximum duty cycle. Output voltage will rise to nearly the input voltage (VIN) level. Possible damage to customer load and/or output stage components may occur. No effect on device.B
FB7PGErratic operation; probable loss of regulation. Possible output voltage increase and damage to customer load.B
PG8ENErratic operation; probable loss of regulation.B
EN9VINThis is a valid connection for the EN input. Enable functionality will be lost; the device will remain on.B
VIN10PGNDDevice will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device.A
PGND11SWDamage to internal power FET(s) and/or other internal circuitsA
Table 4-5 Pin FMA for Device Pins Short-Circuited to VIN
Pin NamePin No.Description of Potential Failure Effect(s)Failure Effect Class
PGND1,11Device will not operate. No output voltage will be generated. Output capacitors will discharge through input short. Large reverse current may damage device.A
VIN2,10No effect.D
N/C3No effect if this pin is not used by customer.D
When used to route the SW node to connect CBOOT (as recommended), the output voltage will rise to nearly the level of VIN. Customer load will be damaged. Possible damage to deviceA
BOOT4Damage to internal circuitsA
VCC5Damage to internal circuits for VIN>5.5 VA
AGND6Possible damage to internal circuits or packageA
FB7Damage to internal circuits will occur for VIN>5.5 V.A
PG8Damage to internal circuits.A
EN9No damage to device. Loss of ENABLE functionality.B
SW12The output voltage will rise to nearly the level of VIN. Customer load will be damaged. Possible damage to deviceA