NJM2352D NJR, NJM2352D Datasheet - Page 9

• Manufacturer Part Number: NJM2352D
• Description: IC LOW POWER SW REG 8 DIP
• Manufacturer: NJR
• Type: Step-Down (Buck), Step-Up (Boost), Invertingr

Specifications of NJM2352D

• Internal Switch(s): No
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 5V, 9V, 24V
• Frequency - Switching: 50kHz
• Voltage - Input: 2.6 ~ 24 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Through Hole
• Package / Case: 8-DIP
• Power - Output: 300mW
• Operating Temperature Range: - 40 C to + 85 C
• Mounting Style: Through Hole
• Duty Cycle (max): 50 %
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Current - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

■ PRINCIPLE OF OPERATION
At point A is the square wave and at point B is the triangular wave. By putting two input signals (A, B) into COMP-2,
output (point C) voltage is held high level during rising period of triangular wave and the switching transistor is kept in the
off condition regardless the COMP-1 output level. So the maximum duty cycle of the NJM2352 is 50%.
Thus function of the COMP-1 is pulse wide modulation. When the AMP's output waveform is D, COMP-1 output is like E,
and NOR GATE output becomes high level only when both inputs, C, E, are low, and so the falling period of triangular
wave is the range of pulse width control.
Ver.2003-07-18
The NJM2352 circuit block is shown on Fig. 1 and timing chart on Fig. 2. Function of COMP-2 is setting dead-time.
The COMP-1 makes on-time of switching transistor longer when the output voltage is high and shorter when it is low.
A
E
C
F
D
B
B
D
A
E
C
F
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