MAX1684 Datasheet, PDF (2/16 Pages) Maxim Integrated Products – Low-Noise, 14V Input, 1A, PWM Step-Down Converters

Low-Noise, 14V Input, 1A, PWM
Step-Down Converters
ABSOLUTE MAXIMUM RATINGS
AIN to AGND ............................................................-0.3 to +15V
IN to PGND ................................................-0.3V to (V_AIN + 0.3V)
LX to PGND .................................................-0.5V to (V_IN + 0.3V)
PGND to AGND ..................................................................±0.3V
SHDN to AGND .........................................-0.3V to (V_AIN + 0.3V)
ILIM/SS, FB, CC, BOOT, REF to AGND .....-0.3V to (V_CVL+ 0.3V)
CVH to IN..................................................................-6V to +0.3V
CVL, STBY, SYNC/PWM to AGND............................-0.3V to +6V
Reference Current ..............................................................±1mA
CVL Current ..........................................................10mA to -1mA
LX Peak Current (Internally Limited) .....................................2.3A
Continuous Power Dissipation (T_A = +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)............667mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec ) ............................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation 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_IN = V _SHDN = +6V, STBY = SYNC/PWM = CVL, V_BOOT = V_OUT, FB = AGND, circuit of Figure 1, T_A = 0°C to +85°C, unless other-
wise noted. Typical values are at T_A = +25°C.)
PARAMETER
Input Voltage Range
Feedback Voltage
Output Voltage (3.3V mode)
Output Load Regulation
Output Current Capability
Output Adjust Range
FB Input Current
SYMBOL
V_FB
V_OUT
I_FB
On-Resistance, P-Channel
On-Resistance, N-Channel
Current Limit in PWM Mode
I_LIM
Pulse-Skipping Current Threshold
CONDITIONS
V_FB = V_OUT, I_LOAD = 0 to 1A
FB = AGND, I_LOAD = = 0 to 1A
V_FB = V_OUT, I_LOAD = 0 to 1A
V_IN = 5V to 14V
BOOT = AGND (Note 1)
V_FB = 1.4V
High-side switch,
I_LX = 1A
V_IN = 6V
V_IN = 2.7V
Low-side switch, V_IN = 2.7V, I_LX = 200mA
SYNC/PWM = low
MIN
2.7
1.238
3.3
1
V_REF
-50
1.2
285
TYP
1.251
3.333
0.01
0.24
0.34
3
1.75
380
MAX
14
1.264
3.365
V_IN
50
0.5
0.8
8
2.3
475
UNITS
V
V
V
%
A
V
nA
Ω
Ω
A
mA
Current Limit in Low-Power
Mode
I_LIMLP STBY = low
285
380
475
mA
Current Limit, N-Channel
Zero Crossing Threshold
Quiescent Power Consumption
SYNC/PWM = high
SYNC/PWM = low
MAX1684
MAX1685
PWM mode,
SYNC/PWM = high,
V_BOOT = 3.3V
(Note 2)
MAX1684
MAX1685
Normal mode, SYNC/PWM = low,
V_BOOT = 3.3V (Note 2)
Low-power mode, STBY = low,
V_BOOT = 3.3V (Note 2)
0.15 0.4
20
50
40
80
13
25
0.9
0.9
A
80
mA
120
33
65
mW
2
0.14 0.27
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