MAX1692 Datasheet, PDF (3/12 Pages) Maxim Integrated Products – Low-Noise, 5.5V-Input, PWM Step-Down Regulator

Low-Noise, 5.5V-Input,
PWM Step-Down Regulator
ELECTRICAL CHARACTERISTICS (continued)
(V_IN = +3.6V, SYNC/PWM = GND, V_LIM = 3.6V, SHDN = IN, circuit of Figure 2; T_A = 0°C to +85°C, unless otherwise noted. Typical
values are at T_A = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
Reference Load Regulation
0 ≤ I_REF ≤ 50µA
3
15
mV
Undervoltage Lockout Threshold
Logic Input High
Logic Input Low
Logic Input Current
UVLO
V_IH
V_IL
V_IN rising, typical hysteresis is 85mV
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
2.3
2.4
2.5
V
2
V
0.4
V
-1
0.1
1
µA
SYNC/PWM Minimum Pulse Width
High or low
500
ns
ELECTRICAL CHARACTERISTICS
(V_IN = +3.6V, SYNC/PWM = GND, V_LIM = 3.6V, SHDN = IN, circuit of Figure 2, T_A = -40°C to +85°C, unless otherwise noted.) (Note 3)
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX UNITS
Input Voltage Range
Output Voltage
V_IN
V_OUT
FB = OUT, V_IN = V_LIM = 2.7V to 5.5V,
I_OUT = 0
FB = OUT, V_IN = 2.7V to 5.5V,
I_OUT = 0 to 600mA, LIM = IN or
I_OUT = 0 to 250mA, LIM = GND
2.7
1.213
1.185
5.5
V
1.285
V
1.285
Output Adjustment Range
Feedback Voltage
(Note 1)
V_FB
FB = OUT, V_IN = V_LIM = 5.5V, I_OUT = 0
(duty cycle = 23%) (Note 2)
REF
1.213
V_IN
V
1.285
V
FB Input Current
P-Channel Current-Limit
Threshold
I_FB
V_FB =1.4V
LIM = GND
LIM = IN
-50
50
nA
0.3
0.9
A
0.7
1.6
N-Channel Current-Limit
Threshold
SYNC/PWM = IN, FB = REF
-15
110
mA
Quiescent Current
Shutdown Supply Current
SYNC/PWM = GND, LX = unconnected,
V_FB = 1.4V
SHDN = LX = GND, includes LX leakage current
140
µA
10
µA
Oscillator Frequency
Reference Output Voltage
Undervoltage Lockout
Threshold
f_OSC
V_REF
UVLO
I_REF = 0
V_IN rising, typical hysteresis is 85mV
630
1.230
2.3
840 kHz
1.268
V
2.5
V
Logic Input High
Logic Input Low
Logic Input Current
V_IH
SHDN, SYNC/PWM, LIM
V_IL
SHDN, SYNC/PWM, LIM
SHDN, SYNC/PWM, LIM
2
V
0.4
V
-1
1
µA
Note 1: Guaranteed by minimum and maximum duty-factor tests.
Note 2: The following equation can be used to calculate FB accuracy for output voltages other than 1.232V:
(see Feedback Voltage vs. Load Current)
V_FB = V_{FB (NOMINAL)} - (Line Reg) (V_OUT / V_IN - 0.23) / 0.77 - (Load Reg)(I_OUT + 0.5 · I_RIPPLE) / I_MAX
where: Line Reg = the line regulation
Load Reg = the load regulation
I_RIPPLE = (1- V_OUT / V_IN) · V_OUT / (f_OSC · L) where L is the inductor value
I_MAX = 250mA (LIM = GND) or 600mA (LIM = IN)
Note 3: Specifications to -40°C are guaranteed by design, not production tested.
_______________________________________________________________________________________ 3