Operating Temperature Range ........................ -40NC to +125NC
Junction Temperature .....................................................+150NC
Storage Temperature Range............................ -65NC to +150NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) ..................................... +260
o
C
PACKAGE THERMAL CHARACTERISTICS (Note 1)
TSSOP
Junction-to-Ambient Thermal Resistance (B
JA
) .......38.3NC/W
Junction-to-Case Thermal Resistance (B
JC
) .................3NC/W
TQFN
Junction-to-Ambient Thermal Resistance (B
JA
) ..........35NC/W
Junction-to-Case Thermal Resistance (B
JC
) ..............2.7NC/W
Note 1:
Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer
board. For detailed information on package thermal considerations, refer to
www.maximintegrated.com/thermal-tutorial.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional opera-
tion of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(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
Supply Voltage Range
Load-Dump Event Supply
Voltage
SYMBOL
V
SUP
,
V
SUPSW
V
SUP_LD
I
SUP
Supply Current
t
LD
< 1s
I
LOAD
= 1.5A
Standby mode, no load, V
OUT
= 5V
I
SUP_STANDBY
Standby mode, no load, V
OUT
= 5V,
T
A
= +25°C
I
SHDN
V
BIAS
V
UVBIAS
V
EN
= 0V
V
SUP
= V
SUPSW
= 6V to 36V
V
BIAS
rising
4.7
2.9
3.5
30
30
5
5
3.1
400
+175
15
60
45
12
5.3
3.3
FA
FA
V
V
mV
NC
NC
CONDITIONS
MIN
3.5
TYP
MAX
36
42
UNITS
V
V
mA
Shutdown Supply Current
BIAS Regulator Voltage
BIAS Undervoltage Lockout
BIAS Undervoltage-Lockout
Hysteresis
Thermal Shutdown Threshold
Thermal-Shutdown Threshold
Hysteresis
Maxim Integrated
2
MAX16977
36V, 2A, 2.2MHz Step-Down Converter
with Low Operating Current
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
OUTPUT VOLTAGE (OUT)
Output Voltage
Skip-Mode Output Voltage
Adjustable Output Voltage
Range
Load Regulation
Line Regulation
BST Input Current
LX Current Limit
Skip-Mode Threshold
Spread Spectrum
Power-Switch On-Resistance
High-Side Switch Leakage
Current
TRANSCONDUCTANCE AMPLIFIER (COMP)
FB Input Current
I
FB
V
FB
FB connected to an external resistive
divider; 0°C < T
A
< +125°C
FB connected to an external resistive
divider; -40°C < T
A
< +125°C
6V < V
SUP
< 36V
V
FB
= 1V, V
BIAS
= 5V (Note 2)
0.99
0.985
10
1.0
1.0
0.02
900
80
f
SW
= 2.2MHz
f
SW
= 1MHz
R
FOSC
= 12kI
T
A
at +25°C
t
FSYNC
(Note 2)
V
FSYNC_HI
V
FSYNC
rising
f
OSC
+
10%
1.4
1
2.05
98
99
2.20
2.35
1
1.01
V
1.015
%/V
FS
ns
%
nA
R
ON
I
BST_ON
I
LX
I
SKIP_TH
Spread spectrum enabled
R
ON
measured between SUPSW and LX,
I
LX
= 1A, V
BIAS
= 5V
V
SUP
= 36V, V
LX
= 0V, T
A
= +25°C
V
OUT
V
OUT_SKIP
V
OUT_ADJ
V
FB
= V
BIAS
, normal operation
No load, V
FB
= V
BIAS
FB connected to external resistive divider
V
FB
= V
BIAS
, 30mA < I
LOAD
< 2A
V
FB
= V
BIAS
, 6V < V
SUPSW
< 36V
High-side on, V
BST
- V
LX
= 5V
(Note 2)
2.4
4.925
4.925
1
0.5
0.02
1.5
3
300
6
70
150
1
2.5
4
5
5
5.075
5.15
10
V
V
V
%
%/V
mA
A
mA
%
mI
FA
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
FB Regulation Voltage
FB Line Regulation
Transconductance (from FB to
COMP)
Minimum On-Time
Maximum Duty Cycle
OSCILLATOR FREQUENCY
Oscillator Frequency
EXTERNAL CLOCK INPUT (FSYNC)
FSYNC Input Current
External Input Clock Acquisition
Time
External Input Clock Frequency
External Input Clock
High Threshold
Maxim Integrated
DV
LINE
g
m
t
ON_MIN
DC
MAX
MHz
FA
Cycles
Hz
V
3
MAX16977
36V, 2A, 2.2MHz Step-Down Converter
with Low Operating Current
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
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