Datasheet

MAX16977
36V, 2A, 2.2MHz Step-Down Converter
with Low Operating Current
3Maxim Integrated
ELECTRICAL CHARACTERISTICS (continued)
(V
SUP
= V
SUPSW
= 14V, V
EN
= 14V, C
BIAS
= 1FF, R
FOSC
= 12kI, T
A
= T
J
= -40NC to +125NC, unless otherwise noted. Typical values
are at T
A
= +25NC.)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
OUTPUT VOLTAGE (OUT)
Output Voltage V
OUT
V
FB
= V
BIAS
, normal operation 4.925 5 5.075 V
Skip-Mode Output Voltage V
OUT_SKIP
No load, V
FB
= V
BIAS
4.925 5 5.15 V
Adjustable Output Voltage
Range
V
OUT_ADJ
FB connected to external resistive divider 1 10 V
Load Regulation V
FB
= V
BIAS
, 30mA < I
LOAD
< 2A 0.5 %
Line Regulation V
FB
= V
BIAS
, 6V < V
SUPSW
< 36V 0.02 %/V
BST Input Current I
BST_ON
High-side on, V
BST
- V
LX
= 5V 1.5 2.5 mA
LX Current Limit I
LX
(Note 2) 2.4 3 4 A
Skip-Mode Threshold I
SKIP_TH
300 mA
Spread Spectrum Spread spectrum enabled 6 %
Power-Switch On-Resistance R
ON
R
ON
measured between SUPSW and LX,
I
LX
= 1A, V
BIAS
= 5V
70 150
mI
High-Side Switch Leakage
Current
V
SUP
= 36V, V
LX
= 0V, T
A
= +25°C
1
FA
TRANSCONDUCTANCE AMPLIFIER (COMP)
FB Input Current I
FB
10 nA
FB Regulation Voltage V
FB
FB connected to an external resistive
divider; 0°C < T
A
< +125°C
0.99 1.0 1.01
V
FB connected to an external resistive
divider; -40°C < T
A
< +125°C
0.985 1.0 1.015
FB Line Regulation
DV
LINE
6V < V
SUP
< 36V 0.02 %/V
Transconductance (from FB to
COMP)
g
m
V
FB
= 1V, V
BIAS
= 5V (Note 2) 900
FS
Minimum On-Time t
ON_MIN
80 ns
Maximum Duty Cycle DC
MAX
f
SW
= 2.2MHz 98
%
f
SW
= 1MHz 99
OSCILLATOR FREQUENCY
Oscillator Frequency
R
FOSC
= 12kI
2.05 2.20 2.35 MHz
EXTERNAL CLOCK INPUT (FSYNC)
FSYNC Input Current
T
A
at +25°C
1
FA
External Input Clock Acquisition
Time
t
FSYNC
1 Cycles
External Input Clock Frequency (Note 2)
f
OSC
+
10%
Hz
External Input Clock
High Threshold
V
FSYNC_HI
V
FSYNC
rising 1.4 V