LM2852YMXA-2.5/NOPB National Semiconductor, LM2852YMXA-2.5/NOPB Datasheet - Page 10

• Manufacturer Part Number: LM2852YMXA-2.5/NOPB
• Description: IC REG SYNC BUCK 2A 2.5V 14TSSOP
• Manufacturer: National Semiconductor
• Series: PowerWise®, SIMPLE SWITCHER®r
• Type: Step-Down (Buck)r

Specifications of LM2852YMXA-2.5/NOPB

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 2.5V
• Current - Output: 2A
• Frequency - Switching: 500kHz
• Voltage - Input: 2.85 ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 14-TSSOP Exposed Pad, 14-eTSSOP 14-HTSSOP
• For Use With: LM2852Y-2.5EVAL - BOARD EVAL LM2852Y-2.5
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Other names: *LM2852YMXA-2.5; *LM2852YMXA-2.5/NOPB; LM2852YMXA-2.5

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Applications Information
falls to a low voltage. During this time, the soft-start voltage
is forced to track the output so that once the short is re-
moved, the LM2852 can restart gracefully from whatever
voltage the output reached during the short circuit event. The
range of soft-start capacitors is therefore restricted to values
1nF to 50nF.
COMPENSATION
The LM2852 provides a highly integrated solution to power
supply design. The compensation of the LM2852, which is
Frequency
(1500kHz)
LM2852Y
LM2852X
(500kHz)
Option
V
OUT
0.8
0.8
1.0
1.0
1.2
1.2
1.5
1.5
1.8
1.8
2.5
2.5
3.3
0.8
0.8
1.0
1.0
1.2
1.2
1.5
1.5
1.8
1.8
2.5
2.5
3.3
(V)
PVIN (V)
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
3.3
5.0
5.0
(Continued)
TABLE 1. Output Filter Values
Min
6.8
10
10
10
10
10
15
10
22
10
22
15
15
L (µH)
1
10
Max
15
15
15
15
15
22
15
22
15
33
10
22
22
type-three, is included on-chip. The benefit to integrated
compensation is straightforward, simple power supply de-
sign. Since the output filter capacitor and inductor values
impact the compensation of the control loop, the range of L,
C and C
OUTPUT FILTER VALUES
Table 1 details the recommended inductor and capacitor
ranges for the LM2852 that are suggested for various typical
output voltages. Values slightly different than those recom-
mended may be used, however the phase margin of the
power supply may be degraded.
ESR
Min
100
100
100
100
100
100
100
100
100
100
68
68
68
values is restricted in order to ensure stability.
C (µF)
10
Max
220
120
180
180
180
120
120
120
120
120
120
120
100
have very low ESR (
designed for ceramic output
Min
100
100
100
capacitors which typically
70
70
70
70
70
70
70
70
95
95
The 1500kHz version is
C
ESR
(mΩ)
Max
200
200
200
200
200
200
200
200
200
200
275
275
275
<
10mΩ.)