Low-Noise, 14V Input, 1A, PWM
Step-Down Converters
ELECTRICAL CHARACTERISTICS (continued)
(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
Quiescent Supply Current
in Dropout
Shutdown Supply Current
LX Leakage Current
Oscillator Frequency
SYNC Capture Range
Maximum Duty Cycle
Constant-Frequency Minimum
Duty Cycle
Reference Output Voltage
Reference Load Regulation
Reference Supply Regulation
CVL Regulator Output Voltage
CVL Dropout Voltage
CVL Undervoltage Lockout
Threshold
CVH with Respect to V
IN
BOOT Switchover Threshold
Thermal Shutdown Threshold
ILIM/SS Source Current
Logic Input High Voltage
Logic Input Low Voltage
Logic Input Current
SYNC/PWM Pulse Width
V
IH
V
IL
V
REF
(Note 3)
I
REF
= 0
-1µA < I
REF
< 50µA
2.7V < V
BOOT
< 5.5V
V
IN
= 3V to 14V, BOOT = AGND,
I
CVL
= 0 to 5mA
BOOT = AGND, I
CVL
= 5mA
BOOT = AGND, CVL falling edge,
typical hysteresis is 40mV
I
CVH
= -1mA
BOOT falling edge,
typical hysteresis is 0.1V
Typical hysteresis is 10°C (Note 4)
V
ILIM/SS
= 1.4V
SHDN, STBY,
SYNC/PWM
SHDN, STBY,
SYNC/PWM
High or low period
3.3
2
0.7
-1
500
1
2.4
-5.0
2.4
2.5
-4.6
2.5
160
4
4.65
2.7
MAX1684
MAX1685
1.238
I
LX
f
OSC
SYMBOL
CONDITIONS
STBY
= low, V
IN
= 2.7V
SHDN
= low
V
IN
= 14V, V
LX
= 0 or 14V,
SHDN
= low
MAX1684
MAX1685
MAX1684
MAX1685
260
520
180
360
100
10
20
1.251
4
0.2
3.0
1.264
15
5
3.15
120
2.6
-4.1
2.6
300
600
MIN
TYP
230
2
MAX
430
6
20
340
680
350
700
UNITS
µA
µA
µA
kHz
kHz
%
%
V
mV
mV
V
mV
V
V
V
°C
µA
V
V
µA
ns
MAX1684/MAX1685
_______________________________________________________________________________________
3
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
