L4979D STMicroelectronics, L4979D Datasheet - Page 4

• Manufacturer Part Number: L4979D
• Description: IC VOLTAGE REG LDO SO-8
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L4979D

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 5V
• Current - Output: 150mA
• Voltage - Input: 5.6 ~ 31 V
• Operating Temperature: -40°C ~ 150°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Polarity: Positive
• Input Voltage Max: 31 V
• Output Voltage: 5 V
• Output Type: Fixed
• Dropout Voltage (max): 0.4 V at 150 mA
• Output Current: 300 mA
• Line Regulation: 25 mV
• Load Regulation: 25 mV
• Voltage Regulation Accuracy: 2 %
• Maximum Operating Temperature: + 150 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Frequency - Switching: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

List of figures
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Figure 14.
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Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Pins connection (top view) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Behavior of output current versus regulated voltage V
Watchdog time diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
SO-8 PC board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Rthj-amb vs PCB copper area in open box free air condition . . . . . . . . . . . . . . . . . . . . . . . 12
SO-8 thermal impedance junction ambient single pulse . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Thermal fitting model of V
SO-20 PC board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Rthj-amb vs PCB copper area in open box free air condition . . . . . . . . . . . . . . . . . . . . . . . 15
SO-20 thermal impedance junction ambient single pulse . . . . . . . . . . . . . . . . . . . . . . . . . 15
Thermal fitting model of V
SO-8 package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
SO-20 package dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
reg
reg
in SO-8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
in SO-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Doc ID 10262 Rev 7
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