LP3907TLX-JJ11/NOPB National Semiconductor, LP3907TLX-JJ11/NOPB Datasheet - Page 27
![IC PMU DUAL DC/DC REG 25USMD](/photos/6/99/69997/tla25aaa_sml.jpg)
LP3907TLX-JJ11/NOPB
Manufacturer Part Number
LP3907TLX-JJ11/NOPB
Description
IC PMU DUAL DC/DC REG 25USMD
Manufacturer
National Semiconductor
Series
PowerWise®r
Type
Step-Down (Buck)r
Specifications of LP3907TLX-JJ11/NOPB
Topology
Step-Down (Buck) Synchronous (2), Linear (LDO) (2)
Function
Any Function
Number Of Outputs
4
Frequency - Switching
2.1MHz
Voltage/current - Output 1
1.2V, 1A
Voltage/current - Output 2
1.8V, 600mA
Voltage/current - Output 3
2.85V, 300mA
W/led Driver
No
W/supervisor
No
W/sequencer
Yes
Voltage - Supply
2.8 V ~ 5.5 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
25-MicroSMD
Current - Output
300mA, 600mA, 1A
Voltage - Output
1.2V, 1.8V
Voltage - Input
2.8 ~ 5.5 V
Power - Output
1.43W
Internal Switch(s)
Yes
Synchronous Rectifier
Yes
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
LP3907TLX-JJ11
If the EN1 and RDY1 are initiated in normal operation, then
nPOR is asserted and deasserted as explained above.
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 ( 5ms )
counter delay is triggered off the EN2 rising edge. nPOR is
still held HIGH for the duration of the mask, whereupon the
nPOR status afterwards will depend on the status of both
RDY1 and RDY2 lines.
NPOR Mask Window
27
In Case 2, we see the case where EN2 is initiated after the
RDY1 triggered programmable delay, but RDY2 never goes
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.
30017813
www.national.com