LM5116MH/NOPB National Semiconductor, LM5116MH/NOPB Datasheet - Page 22

• Manufacturer Part Number: LM5116MH/NOPB
• Description: IC CTRLR SYNCH BUCK 20-TSSOP
• Manufacturer: National Semiconductor
• Series: PowerWise®r
• Type: Step-Down (Buck)r

Specifications of LM5116MH/NOPB

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: 1.22 ~ 80 V
• Current - Output: 20A
• Frequency - Switching: 50kHz ~ 1MHz
• Voltage - Input: 6 ~ 100 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 20-TSSOP Exposed Pad, 20-eTSSOP, 20-HTSSOP
• Dc To Dc Converter Type: Synchronous Buck Controller
• Pin Count: 20
• Input Voltage: 6 to 100V
• Output Voltage: 1.215 to 80V
• Output Current: 3.5A
• Package Type: TSSOP EP
• Mounting: Surface Mount
• Operating Temperature Classification: Automotive
• Operating Temperature (min): -40C
• Operating Temperature (max): 125C
• For Use With: LM5116-12EVAL - BOARD EVALUATION FOR LM5116-12LM5116EVAL - BOARD EVALUATION LM5116
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Lead Free Status / Rohs Status: Compliant
• Other names: LM5116MH

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MODULATOR TRANSFER FUNCTION
The following equations can be used to calculate the control-
to-output transfer function:
K
duty cycle D = V
pensation term. V
Slope compensation is set by m
ternal ramp to the natural ramp. The switching frequency
m
is the effective DC gain of the modulating comparator. The
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-
22
sampling gain is characterized by ω
for the high frequency inductor pole.
For V
For V
For V
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.
SL
SL
SL
without R
with R
with R
OL
= 10,000 (80dB) and ω
RAMP
RAMP
RAMP
to V
to -V
, use I
CC
CC
, use I
, use I
OS
= 25 µA
OS
OS
BW
= 25 µA + V
n
= 25 µA - V
= 2
and Q, which accounts
π
x f
BW
CC
. G
CC
/R
/R
EA(S)
RAMP
RAMP
is the