LM2833XMYEVAL National Semiconductor, LM2833XMYEVAL Datasheet - Page 12

• Manufacturer Part Number: LM2833XMYEVAL
• Description: BOARD EVAL LM2833 1.5MHZ 10MSOP
• Manufacturer: National Semiconductor

Specifications of LM2833XMYEVAL

• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Voltage - Output: 1.2V
• Current - Output: 3A
• Voltage - Input: 3 ~ 5.5V
• Regulator Topology: Buck
• Frequency - Switching: 1.5MHz
• Board Type: Fully Populated
• Utilized Ic / Part: LM2833
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -

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FIGURE 7. Loop Gain and Phase without C
FIGURE 8. Loop Gain and Phase with C
FIGURE 6. Adding a C
FF
Capacitor
30013255
30013237
30013238
FF
FF
12
OUTPUT OVER-VOLTAGE PROTECTION
The LM2833 has a built in output over-voltage comparator
that compares the FB pin voltage to a threshold voltage that
is 15% higher than the internal reference V
pin voltage exceeds this threshold level (typically 0.69V), the
internal PMOS power switch is turned off, which allows the
output voltage to decrease towards regulation.
UNDER-VOLTAGE LOCKOUT
Under-voltage lockout (UVLO) prevents the LM2833 from op-
erating until the input voltage exceeds 2.70V (typical). The
UVLO threshold has approximately 350mV of hysteresis, so
the part will operate until V
Hysteresis prevents the part from turning off during power up
if V
CURRENT LIMIT
The LM2833 uses cycle-by-cycle current limiting to protect
the internal power switch. During each switching cycle, a cur-
rent limit comparator detects if the power switch current ex-
ceeds 4.4A (typical), and turns off the switch until the next
switching cycle begins.
IN
is non-monotonic.
FIGURE 9. Load Step Response without C
FIGURE 10. Load Step Response with C
IN
drops below 2.35V (typical).
REF
. Once the FB
30013245
30013246
FF
FF