LM5116MH National Semiconductor, LM5116MH Datasheet - Page 21

• Manufacturer Part Number: LM5116MH
• Description: IC,SMPS CONTROLLER,CURRENT-MODE,TSSOP,20PIN,PLASTIC
• Manufacturer: National Semiconductor

Specifications of LM5116MH

• Rohs Compliant: NO

For V
made with a simple charge pump from the LO gate output.
Install a resistor from the RAMP pin to the negative VCC.
If a large variation is expected in VCC, say for V
Zener regulator may be added to supply a constant voltage
for R
MODULATOR TRANSFER FUNCTION
The following equations can be used to calculate the control-
to-output transfer function:
RAMP
OUT
FIGURE 14. R
FIGURE 13. R
.
< 7.5V, a negative VCC is required. This can be
RAMP
RAMP
to -VCC for V
to VCC for V
30007573
30007575
OUT
OUT
> 7.5V
< 7.5V
IN
< 11V, a
21
K
duty cycle D = V
pensation term. V
Slope compensation is set by m
ternal ramp to the natural ramp. The switching frequency
sampling gain is characterized by ω
for the high frequency inductor pole.
ERROR AMPLIFIER TRANSFER FUNCTION
The following equations are used to calculate the error am-
plifier transfer function:
Where A
ideal error amplifier gain, which is modified at DC and high
frequency by the open loop gain of the amplifier and the feed-
back divider ratio.
m
is the effective DC gain of the modulating comparator. The
OL
= 10,000 (80dB) and ω
OUT
SL
/ V
is the fixed slope compensation term.
IN
. K
SL
is the proportional slope com-
c
, which is the ratio of the ex-
BW
n
= 2π x f
and Q, which accounts
BW
. G
www.national.com
EA(S)
is the