LM5009MM National Semiconductor, LM5009MM Datasheet - Page 3

• Manufacturer Part Number: LM5009MM
• Description: IC,SMPS CONTROLLER,VOLTAGE-MODE,TSSOP,8PIN,PLASTIC
• Manufacturer: National Semiconductor

Specifications of LM5009MM

• Rohs Compliant: NO

Pin Descriptions
Pin
1
2
3
4
5
6
7
8
RON/SD
Name
RTN
VCC
BST
RCL
VIN
SW
FB
EP
Switching output
Boost Pin
Current Limit off-time set pin
Ground pin
Feedback input from Regulated Output
On-time set pin
Output from the internal high voltage startup
regulator. Regulated at 7.0V.
Input voltage
Exposed Pad (LLP Package only)
Description
3
Power switching output. Connect to the inductor,
re-circulating diode, and bootstrap capacitor.
An external capacitor is required between the BST
and the SW pins. A 0.01µF ceramic capacitor is
recommended. An internal diode charges the
capacitor from V
A resistor between this pin and RTN sets the
off-time when current limit is detected. The off-time
is preset to 35µs if FB = 0V.
Ground for the entire circuit.
This pin is connected to the inverting input of the
internal regulation comparator. The regulation
threshold is 2.5V.
A resistor between this pin and VIN sets the switch
on-time as a function of V
recommended on-time is 250ns at the maximum
input voltage. This pin can be used for remote
shutdown.
If an auxiliary voltage is available to raise the
voltage on this pin above the regulation setpoint
(7V), the internal series pass regulator will
shutdown, reducing the IC power dissipation. Do not
exceed 14V. This voltage provides gate drive power
for the internal Buck switch. An internal diode is
provided between this pin and the BST pin. A local
0.1µF decoupling capacitor is required.
Recommended operating range: 9.5V to 95V.
Exposed metal pad on the underside of the device.
It is recommended to connect this to the PC board
ground plane to aid in heat dissipation.
Application Information
CC
.
IN
. The minimum
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