L4972AD STMicroelectronics, L4972AD Datasheet - Page 9

• Manufacturer Part Number: L4972AD
• Description: IC REG SW 2A 5.1-40V STDN 20SOIC
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L4972AD

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 5.1 ~ 40 V
• Current - Output: 2A
• Frequency - Switching: 100kHz
• Voltage - Input: 15 ~ 50 V
• Operating Temperature: -40°C ~ 150°C
• Mounting Type: Surface Mount
• Package / Case: 20-SOIC (7.5mm Width)
• Power - Output: 3.75W
• Output Voltage: 40 V
• Output Current: 2 A
• Input Voltage: 15 V to 50 V
• Switching Frequency: 90 KHz to 110 KHz
• Operating Temperature Range: - 40 C to + 150 C
• Mounting Style: SMD/SMT
• Duty Cycle (max): 90 %
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-4206-5; 497-4206-5; 497-4207-5

PART LIST
R1 = 30KΩ
R2 = 10KΩ
R3 = 15KΩ
R4 = 30KΩ
R5 = 22Ω
R6 = 4.7KΩ
R7 = see table 6
R8 = OPTION
R9 = 4.7KΩ
* C1 = C2 = 1000mF 63V EYF (ROE)
** C12 = C13 = C14 = 100µF 40V EKR (ROE)
* 2 capacitors in parallel to increase input RMS current capability.
* * 3 capacitors in parallel to reduce total output ESR.
Table 6.
Note:
In the Test and Application Circuit for L4972D are not
mounted C2, C14 and R8.
Table 7. Suggested Boostrap Capacitors
C3 = C4 = C5 = C6 = 2,2µF 50V
C7 = 390pF Film
C8 = 22nF MKT 1837 (ERO)
C9 = 2.7nF KP 1830 (ERO)
C10 = 0.33µF Film
C11 = 1nF
C15 = 1µF Film
D1 = STPS5L60
L1 = 150µH
core 58310 MAGNETICS
45 TURNS 0.91mm (AWG 19)
COGEMA 949181
12V
15V
18V
24V
Operating Frequency
V
0
f = 100KHz
f = 200KHz
f = 500KHz
f = 20KHz
f = 50KHz
4.7kΩ
4.7kΩ
4.7kΩ
4.7kΩ
R
9
Boostrap Cap.c10
≥680nF
≥470nF
≥330nF
≥220nF
≥100nF
6.2kΩ
9.1kΩ
12Ω
18Ω
R
7
L4972A
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