Rainbow Electronics MAX8720 - Manual (Page 6)

MAX8720
Dynamically Adjustable 6-Bit VID
Step-Down Controller
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ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ =15V, SHDN = SKIP = V DD = V CC = +5V, V OUT = 1.25V, T A = -40°C to +85°C, unless otherwise noted.
Typical values are at T A = +25°C.) (Note 4)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Output Overvoltage Trip
Threshold
2.20 2.30 V
Output Undervoltage-Protection
Trip Threshold
With respect to unloaded output voltage 65 75 %
PGOOD Lower Trip Threshold
Measured at FB with respect to unloaded
output voltage, hysteresis = 1%
-17.5 -12.5 %
PGOOD Upper Trip Threshold
Measured at FB with respect to unloaded
output voltage, hysteresis = 1%
+12.5 +17.5 %
CURRENT LIMIT
ILIM Adjustment Range 0.5 V REF V
Current-Limit Threshold (Fixed) V LIMIT V PGND - V LX , ILIM = V CC 80 115 mV
V ILIM = 2.00V 160 240 Current-Limit Threshold
(Adjustable)
V LIMIT V PGND - V LX
V ILIM = 0.50V 33 65
mV
Current-Limit Threshold
(Negative)
V NEG V LX - V PGND , SKIP = ILIM = V CC -140 -85 mV
GATE DRIVERS
QSOP package 3.5 DH Gate-Driver On-Resistance
(Note 3)
R DH BST-LX forced to 5V
TQFN package 4.5
Ω
QSOP package 3.5
DL, high state
TQFN package 4.0
DL Gate-Driver On-Resistance
(Note 3)
R DL
DL, low state 1.0
Ω
INPUTS AND OUTPUTS
Logic high 2.4
Logic low 0.4 SHDN Input Level V SHDN
No-fault mode 12 15
V
Logic Input High Voltage V IH D0–D5, SKIP, SUS 2.4 V
Logic Input Low Voltage V IL D0–D5, SKIP, SUS 0.8 V
High
V CC -
0.2
Open 3.15 3.85
REF 1.65 2.35
Four-Level Input Logic TON, S0, S1
GND 0.5
V
Note 2: On-time specifications are measured from 50% to 50% at the DH pin, with LX forced to 0, BST forced to 5V, and a 500pF
capacitor from DH to LX to simulate external MOSFET gate capacitance. Actual in-circuit times may be different due to
MOSFET switching speeds.
Note 3: Production testing limitations due to package handling require relaxed maximum on-resistance specifications for the thin
QFN package. The QSOP and thin QFN package contain the same die, and the thin QFN package imposes no additional
resistance in the circuit.
Note 4: Specifications to -40°C are guaranteed by design, not production tested.