Rainbow Electronics MAX1844 - Manual (Page 4)

MAX1844
High-Speed Step-Down Controller with
Accurate Current Limit for Notebook Computers
4 _______________________________________________________________________________________
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ = 15V, V
CC
= V
DD
= 5V, SKIP = GND, T
A
= 0 ° C to +85 ° C , unless otherwise noted. Typical values are at
T
A
= +25 ° C.)
PARAMETER CONDITIONS MIN TYP MAX UNITS
MAX1844EEP 1.5 5 DH Gate-Driver On-Resistance
(Note 4)
BST - LX forced to 5V
MAX1844EGP 1.5 6
Ω
DL, high state 1.5 5 DL Gate-Driver On-Resistance
(Note 4) DL, low state 0.5 1.7
Ω
DH Gate-Driver
Source/Sink Current
DH forced to 2.5V, BST-LX forced to 5V 1 A
DL Gate-Driver Source Current DL forced to 2.5V 1 A
DL Gate-Driver Sink Current DL forced to 5V 3 A
DL rising 35
Dead Time
DH rising 26
ns
Logic Input High Voltage LATCH, SHDN, SKIP 2.4 V
Logic Input Low Voltage LATCH, SHDN, SKIP 0.8 V
Logic Input Current LATCH, SHDN, SKIP -1 +1 µA
Dual Mode Threshold, Low OVP, UVP, FB 0.15 0.20 0.25 V
OVP, UVP V CC - 1.5 V CC - 0.4
Dual Mode Threshold, High
FB 1.9 2.0 2.1
V
TON V CC Level V CC - 0.4 V
TON Float Voltage 3.15 3.85 V
TON Reference Level 1.65 2.35 V
TON GND Level 0.5 V
TON Input Current Forced to GND or V CC -3 +3 µA
ILIM Input Leakage Current -100 0 +100 nA
PARAMETER CONDITIONS MIN TYP MAX UNITS
Battery voltage, V+ 2 28
Input Voltage Range
V CC , V DD 4.5 5.5
V
FB = OUT 0.985 1.015
FB = GND 2.462 2.538
Error Comparator Threshold
(DC Output Voltage Accuracy)
(Note 1)
V+ = 4.5V to 28V,
SKIP = V
CC
FB = V CC 1.773 1.827
V
TON = GND (600kHz) 140 180
TON = REF(450kHz) 175 225
TON = Unconnected (300kHz) 260 320
On-Time
V+ = 24V,
V OUT = 2V
(Note 2)
TON = V CC (200kHz) 380 470
ns
ELECTRICAL CHARACTERISTICS
(Circuit of Figure 1, V+ = 15V, V CC = V DD = 5V, SKIP = GND, T A = -40
°
C to +85
°
C , unless otherwise noted.) (Note 3)