Rainbow Electronics MAX1639 - Manual (Page 3)

ELECTRICAL CHARACTERISTICS (continued)
(V
DD
= V
CC
= +5V, PGND = AGND = 0V, FREQ = REF, T A = 0°C to +85°C , unless otherwise noted.)
MAX1639
_______________________________________________________________________________________ 3
High-Speed Step-Down Controller with
Synchronous Rectification for CPU Power
15 38 70
mV
FB = 0V (foldback)
Current-Limit Trip Voltage
DL On-Resistance Ω
50 µA BST = 12V, LX = 7V, REF = GND BST Leakage Current
1536 1 / f OSC To full current limit Soft-Start Time
85 100 115 FB = 1.1V
FB Input Current
CC2 Clamp Voltage
PARAMETER MIN TYP MAX UNITS
FREQ Input Current 4 µA
±0.1 µA
2.4 3.0
V
4 V CC
CC2 Source/Sink Current 100 µA
0.7 2 DH On-Resistance
Maximum
0.7 2
Ω
DH, DL Source/Sink Current 2 A
DH, DL Dead Time 0 30 ns
CONDITIONS
Minimum
30mV overdrive
BST - LX = 4.5V
V
DD
= 4.5V
DH = DL = 2.5V
ELECTRICAL CHARACTERISTICS
(V DD = V CC = +5V, PGND = AGND = 0V, FREQ = REF, T A = -40°C to +85°C , unless otherwise noted.) (Note 1)
Note 1: Specifications from 0°C to -40°C are guaranteed by design, not production tested.
FREQ = REF
FREQ = V CC
BST - LX = 4.5V
FREQ = V CC
Falling FB, 1% hysteresis with respect to V REF
Rising FB, 1% hysteresis with respect to V REF
FREQ = AGND
V DD = 4.5V
Ω
2
% 84
DL On-Resistance
V CC rising edge, 1% hysteresis
Ω
V
CC
= V
DD
2
CONDITIONS
510 690
Maximum Duty Cycle
800 1200
DH On-Resistance
Switching Frequency
FB = 1.1V Current-Limit Trip Voltage mV 70 130
6 10
kHz
240 360
%
-8 -4
PWROK Trip Level
V 3.9 4.3 Input Undervoltage Range
V 4.5 5.5 Input Voltage Range
UNITS MIN TYP MAX PARAMETER
CC2 Transconductance
CC1 Output Resistance 10 k
Ω
1 mmho
CSH, CSL Input Current 50 µA CSH = CSL = 1.1V
V CC = V DD =
5.5V
mA
12
V DD Supply Current
3
Includes line and load regulation errors
No load
V 1.072 1.128 FB Voltage
V 3.448 3.553 Reference Voltage
V CC = V DD = 5.5V, FB forced 60mV above
regulation point, operating or shutdown mode
mA 0.2 V DD Supply Current
Operating mode FB overdrive = 60mV
VREF = 0V Shutdown mode