LM3406HVEVAL National Semiconductor, LM3406HVEVAL Datasheet - Page 11

• Manufacturer Part Number: LM3406HVEVAL
• Description: LM3406/06HV 1.5A Constant Current Buck Regulator for Driving High Power LEDs; Qty per Container: 1/
• Manufacturer: National Semiconductor

LOW POWER SHUTDOWN
The LM3406/06HV can be placed into a low power state (I
SD
MOSFET as shown in
the 2N7000, 2N3904, or equivalent are recommended de-
vices for putting the LM3406/06HV into low power shutdown.
Logic gates can also be used to shut down the LM3406/06HV
THERMAL SHUTDOWN
Internal thermal shutdown circuitry is provided to protect the
IC in the event that the maximum junction temperature is ex-
ceeded. The threshold for thermal shutdown is 165°C with a
= 240 µA) by grounding the RON pin with a signal-level
Figure 5
. Low power MOSFETs like
FIGURE 4. Two Methods of Output Open Circuit Protection
FIGURE 5. Low Power Shutdown
IN-
11
as 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 longer on-times 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
25°C hysteresis (both values typical). During thermal shut-
down the MOSFET and driver are disabled.
30020312
30020311
SNS
.
www.national.com