L5985TR STMicroelectronics, L5985TR Datasheet - Page 32

• Manufacturer Part Number: L5985TR
• Description: IC REG SW 2A STEP DOWN 8-VFQFPN
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L5985TR

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 0.6 ~ 18 V
• Current - Output: 2A
• Frequency - Switching: 250kHz ~ 1MHz
• Voltage - Input: 2.9 ~ 18 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-VFQFN, 8-VFQFPN
• Power - Output: 1.5W
• Output Voltage: 3 V
• Output Current: 2 A
• Input Voltage: 2.9 V to 18 V
• Switching Frequency: 220 KHz to 275 KHz
• Operating Temperature Range: - 40 C to + 150 C
• Mounting Style: SMD/SMT
• Duty Cycle (max): 100 %
• For Use With: 497-6387 - BOARD EVAL FOR L5985
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6861-2; L5985TR

Application information
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Figure 28. Load regulation
Figure 30. Load transient form 0.3 A to 1.3 A
Figure 32. Short circuit behavior
V
V
1V/div
1V/div
OUT
OUT
V
V
V
V
AC coupled
AC coupled
AC coupled
AC coupled
100mV/div
100mV/div
100mV/div
100mV/div
Load slew rate = 2.5A/us
Load slew rate = 2.5A/us
I
I
I
I
0.5A/div
0.5A/div
0.5A/div
0.5A/div
OUT
OUT
OUT
OUT
L
L
L
L
0.6
0.5
0.4
0.3
0.2
0.1
0
OUT
OUT
10V/div
10V/div
OUTPUT
OUTPUT
SHORTED
SHORTED
0
F
SW
=250KHz
I
I
500mA/div
500mA/div
L
L
0.5
V
CC
=12V
Io [A]
1
Time base 5ms/div
Time base 5ms/div
1.5
V
CC
C
C
C
C
L=6.8uH
L=6.8uH
L=6.8uH
L=6.8uH
F
F
F
F
Timescale
Timescale
Timescale
Timescale
100us/div
100us/div
100us/div
100us/div
V
SW
SW
SW
SW
=3.3V
OUT
OUT
OUT
OUT
CC
=500kHz
=500kHz
=500kHz
=500kHz
=47uF
=47uF
=47uF
=47uF
=5.0V
Doc ID 13006 Rev 5
2
Figure 29. Line regulation
Figure 31. Soft-start
-0.2
0.8
0.6
0.4
0.2
1
0
2
I
I
500mA/div
500mA/div
L
L
4
6
Time base 1ms/div
Time base 1ms/div
8
VCC [V]
10
12
14
16
V
V
500mV/div
500mV/div
V
V
200mV/div
200mV/div
OUT
OUT
FB
FB
Io=2A
Io=1A
L5985
18