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.
Continuous Power Dissipation (T
A
= +70NC)
TSSOP (derate 26.1mW/
o
C above +70NC) .......... 2088.8mW*
TQFN (derate 28.6mW/
o
C above +70NC) ............ 2285.7mW*
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.
ELECTRICAL CHARACTERISTICS
(V
SUP
= V
SUPSW
= 14V, V
EN
= 14V, R
FOSC
= 66.5kI, 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
OUTPUT VOLTAGE (OUT)
Output Voltage
Maxim Integrated
V
OUT
V
FB
= V
BIAS,
normal operation
4.925
5
5.075
V
2
MAX16909
36V, 220kHz to 1MHz Step-Down Converter
with Low Operating Current
ELECTRICAL CHARACTERISTICS (continued)
(V
SUP
= V
SUPSW
= 14V, V
EN
= 14V, R
FOSC
= 66.5kI, T
A
= T
J
= -40NC to +125NC, unless otherwise noted. Typical values are at
T
A
= +25NC.)
PARAMETER
Skip-Mode Output Voltage
Adjustable Output Voltage
Range
Load Regulation
Line Regulation
BST Input Current
LX Current Limit
Skip-Mode Threshold
Power-Switch On-Resistance
High-Side Switch Leakage
Current
TRANSCONDUCTANCE AMPLIFIER (COMP)
FB Input Current
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
External Input Clock
Low Threshold
Soft-Start Time
V
FSYNC_HI
V
FSYNC_LO
t
SS
t
FSYNC
(Note 2)
V
FSYNC
rising
V
FSYNC
falling
8.5
f
OSC
+
10%
1.4
0.4
T
A
= +25°C
1
1
FA
Cycles
Hz
V
V
ms
R
FOSC
= 66.5kI
360
400
444
kHz
I
FB
V
FB
DV
LINE
g
m
t
ON_MIN
DC
MAX
FB connected to an external resistive
divider; 0°C < T
A
< +125°C
-40°C < T
A
< +125°C
6V < V
SUP
< 36V
V
FB
= 1V, V
BIAS
= 5V (Note 2)
(Note 2)
f
SW
= 1MHz
f
SW
= 220kHz
0.99
0.985
10
1.0
1.0
0.02
900
110
98
99
1.01
1.015
%/V
FS
ns
%
nA
V
I
BST_ON
I
LX
I
SKIP_TH
R
ON
R
ON
measured between SUPSW and LX,
I
LX
= 1A, V
BIAS
= 5V
V
SUP
= 36V, V
LX
= 0V, T
A
= +25°C
SYMBOL
V
OUT_SKIP
V
OUT_ADJ
CONDITIONS
No load, V
FB
= V
BIAS
FB connected to external resistive divider
V
FB
= V
BIAS
, 30mA < I
LOAD
< 3A
V
FB
= V
BIAS
, 6V < V
SUPSW
< 36V
High-side on, V
BST
- V
LX
= 5V
(Note 2)
3.4
MIN
4.925
1
0.5
0.02
1.5
4.1
300
70
150
1
2.5
6
TYP
5
MAX
5.15
10
UNITS
V
V
%
%/V
mA
A
mA
mI
FA
Maxim Integrated
3
MAX16909
36V, 220kHz to 1MHz Step-Down Converter
with Low Operating Current
ELECTRICAL CHARACTERISTICS (continued)
(V
SUP
= V
SUPSW
= 14V, V
EN
= 14V, R
FOSC
= 66.5kI, T
A
= T
J
= -40NC to +125NC, unless otherwise noted. Typical values are at
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