Rainbow Electronics MAX1855 - Manual (Page 4)

MAX1716/MAX1854/MAX1855
High-Speed, Adjustable, Synchronous Step-Down
Controllers with Integrated Voltage Positioning
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ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ = +15V, V CC = V DD = 5V, SKIP = V CC , VPS = PGND, 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
VGATE Lower Trip Threshold
Measured at FB with respect to unloaded
output voltage, falling edge
-12.5 -10 -7.5 %
VGATE Upper Trip Threshold
Measured at FB with respect to unloaded
output voltage, rising edge
7.5 10 12.5 %
VGATE Propagation Delay
Falling edge, FB forced 2% below or above
VGATE trip threshold
1.5 µs
VGATE Output Low Voltage I SINK = 1mA 0.4 V
VGATE Leakage Current High state, forced to 5.5V 1 µA
GATE DRIVERS
DH Gate Driver On-Resistance R ON ( D H ) V BST - V LX forced to 5V 1.3 5 Ω
High state (pullup) 1.5 5
DL Gate Driver On-Resistance R ON(DL)
Low state (pulldown) 0.5 1.7
Ω
DH Gate Driver Source/Sink
Current
I DH DH forced to 2.5V, V BST - V LX forced to 5V 1 A
DL Gate Drive Sink Current I DL DL forced to 5V 3 A
DL Gate Driver Source Current I DL DL forced to 2.5V 1 A
DL rising 35
Dead-Time
DH rising 26
ns
LOGIC AND I/O
Logic Input High Voltage V IH D0 −D4, SHDN, SKIP 2.4 V
Logic Input Low Voltage V IL D0 −D4, SHDN, SKIP 0.8 V
TON = V CC (200kHz operation) V CC - 0.4
TON = open (300kHz operation) 3.15 3.85
TON = REF (400kHz operation) 1.65 2.35
TON Input Levels
TON = GND (550kHz operation) 0.5
V
TON = GND or V CC -3 3
Logic Input Current
SHDN, SKIP = GND or V
CC -1 1
µA
D0 −D4 Pullup Current D0 −D4 = GND 3 5 10 µA
SKIP No-Fault Mode Current
T A = +25°C -1.5 -0.1 mA