LM3678SD-1.2/NOPB National Semiconductor, LM3678SD-1.2/NOPB Datasheet - Page 3

• Manufacturer Part Number: LM3678SD-1.2/NOPB
• Description: IC CONV DC-DC STDN LV 1.5A 10LLP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: Step-Down (Buck)r

Specifications of LM3678SD-1.2/NOPB

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 0.8V, 1.2V
• Current - Output: 1.5A
• Frequency - Switching: 3.3MHz
• Voltage - Input: 2.5 ~ 5.5 V
• Operating Temperature: -30°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-LLP
• For Use With: LM3678SD-1.2EV - BOARD EVAL FOR LM3678SD-1.2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Other names: LM3678SD-1.2TR

Connection Diagram and Package Mark Information
Pin Descriptions
Ordering Information
Voltage Option
0.8V/1.2V
Pin #
DAP
10
1
2
3
4
5
6
7
8
9
LM3678SDE-1.2
LM3678SD-1.2
LM3678SDX-1.2
VSELECT
PGOOD
Order Number
Top View
Name
PWM
GND
GND
VDD
VDD
DAP
SW
EN
FB
Description
Power Ground pin.
Analog Ground Pin
Switching node connection to the internal PFET switch and NFET synchronous rectifier
Analog supply input. Connect to the input filter capacitor (Figure 1).
Power supply Input. Connect to the input filter capacitor (Figure 1).
Output voltage select ( For example)
VSELECT = LOW, V
VSELECT = HIGH , V
Power Good Flag. This commom drain logic output is pulled to ground when the output
voltage is not within +/-7.5% of regulation.
Connect PWM pin to VIN.
Enable pin. The device is in shutdown mode when voltage to this pin is <0.4V and enabled
when >1.0V. Do not leave this pin floating.
Feedback analog input. Connect directly to the output filter capacitor for fixed voltage
versions.
Die Attach Pad, connect the DAP to GND on PCB layout to enhance thermal
performance. It should not be used as a primary ground connection.
20204502
Package Marking
S021B
S021B
S021B
3
OUT
OUT
= 0.8V
= 1.2V
Bottom View
1000 units, Tape-and-Reel
4500 units, Tape-and-Reel
250 units, Tape-and-Reel
Supplied As
20204503
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