Low-Voltage, Precision Step-Down
Controller for Portable CPU Power
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, V+ = 15V, SYNC = VL = V
CC
, I
VL
= 0mA, I
REF
= 0mA,
T
A
= -40°C to +85°C,
unless otherwise noted.) (Note 1)
PARAMETER
OSCILLATOR
Oscillator Frequency
SYNC Input Pulse Width High
SYNC Input Pulse Width Low
SYNC Input Rise/Fall Time
SYNC Input Frequency Range
OVERVOLTAGE PROTECTION
Overvoltage Trip Threshold
Catastrophic Output Undervoltage
Lockout Threshold
RESET
Trip Threshold
INPUTS AND OUTPUTS
Logic Input Voltage High
Logic Input Voltage Low
RESET
Output Voltage Low
Gate-Driver On-Resistance
SHDN, SKIP,
OVP, SYNC
SHDN, SKIP,
OVP, SYNC
I
SINK
= 4mA
High or low, DH or DL
2.4
0.8
0.4
7
V
V
V
Ω
FB, with respect to regulation point
% of nominal output
Falling edge (hysteresis = 1%)
3.5
60
-7
10
80
-1.5
%
%
%
Guaranteed by design
240
SYNC = V
CC
SYNC = GND
270
170
200
200
200
340
330
230
kHz
ns
ns
ns
kHz
CONDITIONS
MIN
TYP
MAX
UNITS
MAX1636
Note 1:
Specifications to -40°C are guaranteed by design and not production tested.
__________________________________________Typical Operating Characteristics
(Circuit of Figure 1, V
IN
= 7V, T
A
= +25°C, unless otherwise noted.)
EFFICIENCY vs. LOAD CURRENT
(3.3V/3A CIRCUIT)
MAX1636 TOC01
EFFICIENCY vs. LOAD CURRENT
(5V/3A CIRCUIT)
MAX1636 TOC02
EFFICIENCY vs. LOAD CURRENT
(1.8V/1A CIRCUIT)
MAX1636 TOC03
100
V
IN
= 7V
90
EFFICIENCY (%)
V
IN
= 15V
100
V
IN
= 7V
90
EFFICIENCY (%)
V
IN
= 15V
100
90
EFFICIENCY (%)
V
IN
= 7V
80
V
IN
= 22V
V
IN
= 30V
80
V
IN
= 22V
70
V
IN
= 30V
80
V
IN
= 15V
70
V
IN
= 22V
70
60
60
60
50
1m
10m
100m
LOAD CURRENT (A)
1
10
50
1m
10m
100m
LOAD CURRENT (A)
1
10
50
1m
10m
100m
LOAD CURRENT (A)
1
10
_______________________________________________________________________________________
5
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
