LM3402MRX National Semiconductor, LM3402MRX Datasheet - Page 13

• Manufacturer Part Number: LM3402MRX
• Description: LM3402/LM3402HV 0.5A Constant Current Buck Regulator for Driving High Power LEDs; Package: PSOP; No of Pins: 8; Qty per Container: 2500; Container: Reel
• Manufacturer: National Semiconductor

LOW POWER SHUTDOWN
The LM3402/02HV can be switched to a low power state (I
SD
MOSFET as shown in Figure 3. Low power MOSFETs like the
2N7000, 2N3904, or equivalent are recommended devices
for putting the LM3402/02HV into low power shutdown. Logic
gates can also be used to shut down the LM3402/02HV as
THERMAL SHUTDOWN
Internal thermal shutdown circuitry is provided to protect the
IC in the event that the maximum junction temperature is ex-
= 90 µA) by grounding the RON pin with a signal-level
FIGURE 3. Low Power Shutdown
IN-
13
long as the logic low voltage is below the over temperature
minimum threshold of 0.3V. Noise filter circuitry on the RON
pin can cause a few pulses with a longer on-time than normal
after RON is grounded or released. In these cases the OVP/
OCP comparator will ensure that the peak inductor or LED
current does not exceed 300 mV / R
ceeded. The threshold for thermal shutdown is 165°C with a
25°C hysteresis (both values typical). During thermal shut-
down the MOSFET and driver are disabled.
20192113
SNS
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