LM26480SQ-AA/NOPB National Semiconductor, LM26480SQ-AA/NOPB Datasheet - Page 19

• Manufacturer Part Number: LM26480SQ-AA/NOPB
• Description: IC REG BUCK/LDO DUAL 1.5A 24LLP
• Manufacturer: National Semiconductor

Specifications of LM26480SQ-AA/NOPB

• Applications: Processor
• Voltage - Supply: 2.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 24-LLP
• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Pin Count: 24
• Mounting: Surface Mount
• Package Type: LLP EP
• Case Length: 4mm
• Screening Level: Industrial
• For Use With: LM26480SQ-AAEV - BOARD EVALUATION LM26480SQ-AA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Supply: -
• Lead Free Status / Rohs Status: Compliant
• Other names: LM26480SQ-AATR

In Case 1, we see that case where EN2 and RDY2 are initi-
ated after triggered programmable delay. To prevent the
nPOR being asserted again, a masked window (5 ms) counter
delay is triggered off the EN2 rising edge. NPOR is still held
HIGH for the duration of the mask, whereupon the nPOR sta-
tus afterwards will depend on the status of both RDY1 and
RDY2 lines.
In Case 2, we see the case where EN2 is initiated after the
RDY1 triggered programmable delay, but RDY2 never goes
NPOR Mask Window
19
HIGH (Buck2 never turns on). Normal operation operation of
nPOR occurs wilth respect to EN1 and RDY1, and the nPOR
signal is held HIGH for the duration of the mask window. We
see that nPOR goes LOW after the masking window has
timed out because it is now dependent on RDY1 and RDY2,
where RDY2 is LOW.
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