MAX1536 Datasheet, PDF (5/19 Pages) Maxim Integrated Products – 3.6A, 1.4MHz, Low-Voltage, Internal-Switch Step-Down Regulator with Dynamic Output Voltage Control

3.6A, 1.4MHz, Low-Voltage, Internal-Switch Step-
Down Regulator with Dynamic Output Voltage Control
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V_IN = V_CC = V_SHDN = +3.3V, V_REFIN = +1.5V, SKIP = AGND, T_A = -40°C to +85°C, unless otherwise noted.) (Note 5)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
INPUTS AND OUTPUTS
Logic Input Threshold
V _SHDN,
V _SKIP,
V _GATE
SHDN, SKIP, GATE, V_IN = V_CC = +3.3V,
rising edge, hysteresis = 100mV
SHDN, SKIP, GATE, V_IN = V_CC = +5.0V,
rising edge, hysteresis = 100mV
0.9
1.15
1.6
V
1.95
FBLANK Logic Thresholds
V_FBLANK
FBLANK = V_CC
FBLANK = REF
FBLANK = open
V_CC - 0.2
1.8
0.8
2.2
V
1.2
FBLANK = AGND
0.2
OD On-Resistance
R_OD GATE = V_CC
25
Ω
OD On-Resistance
R_OD GATE = AGND
25
Ω
Note 2: Guaranteed by design and not production tested.
Note 3: To limit input surge currents, the current-limit threshold is set to 25% of its final value (25% x 4.8A = 1.2A) when the
MAX1536 is enabled or powered up. The current-limit threshold is increased by 25% every 256 LX cycles. The current-limit
threshold is at its final level of 4.8A after 768 LX cycles. See the Internal Soft-Start Circuit section.
Note 4: The upper and lower PGOOD thresholds are expressed as a ratio of V_FB with respect to V_REFIN.
VFB-VREFIN _x100%
VREFIN
Note 5: Specifications to -40°C are guaranteed by design and are not production tested.
Typical Operating Characteristics
(MAX1536 Circuit of Figure 1, T_A = +25°C, unless otherwise noted.)
EFFICIENCY vs. OUTPUT CURRENT
(V_IN = 5V, L = 1.5μH)
100
PWM MODE
90
IDLE MODE
80
70
60
V_OUT = 2.5V
R_TOFF = 54.9kΩ
50
40
V_OUT = 1.8V
R_TOFF = 93.1kΩ
30
20
V_OUT = 0.7V
10
R_TOFF = 200kΩ
0
0.001 0.01
0.1
1
10
OUTPUT CURRENT (A)
OUTPUT VOLTAGE vs. OUTPUT CURRENT
(V_IN = 5V, L = 1.5μH)
1.806
R_TOFF = 93.1kΩ
1.804
1.802
1.800
1.798
IDLE MODE
PWM MODE
1.796
1.794
0.001
0.01
0.1
1
10
OUTPUT CURRENT (A)
EFFICIENCY vs. OUTPUT CURRENT
(V_IN = 3.3V, L = 1.2μH)
100
90
80
70
60
50
40
30
20
10
0
0.001
V_OUT = 2.5V
R_TOFF = 42.2kΩ
V_OUT = 1.8V
R_TOFF = 75kΩ
V_OUT = 0.7V
R_TOFF = 165kΩ
PWM MODE
IDLE MODE
0.01
0.1
1
10
OUTPUT CURRENT (A)
_______________________________________________________________________________________ 5