Electrical characteristics (continued) – Rainbow Electronics MAX1775 User Manual
Page 5
MAX1775
Dual-Output Step-Down
DC-DC Converter for PDA/Palmtop Computers
_______________________________________________________________________________________
5
ELECTRICAL CHARACTERISTICS (continued)
(V
IN
= +12V, V
MAIN
= V
INC
= V
CS-
= V
CS+
= +3.3V, V
CORE
= +1.8V, Circuit of Figure 4, T
A
-40°C to +85°C, unless otherwise noted.)
(Note 2)
PARAMETER
SYMBOL
CONDITIONS
MIN
MAX
UNITS
Maximum Duty Cycle
100
%
Minimum On-Time
200
650
ns
Minimum Off-Time
200
650
ns
CORE REGULATOR
Input Voltage Range
V
INC
2.6
5.5
V
V
INC
rising
2.39
2.55
INC Undervoltage Lockout
V
INC
falling
2.29
2.45
V
Core Output Voltage Adjust
Range
1.0
5.0
V
Maximum Core Load Current
(Note 1)
1
A
FBC Regulation Threshold
V
FBC
V
INC
= +2.5V to +5.5V, I
OUTC
= 0 to 200mA
0.97
1.03
V
FBC Input Current
I
FBC
V
FBC
= +1.3V
-0.1
0.1
µA
Dropout Voltage (INC to LXC)
I
OUTC
= 400mA
0.2
V
LXC Leakage Current
I
LXC
V
INC
= +5.5V, V
LXC
= 0 to +5.5V
-10
10
µA
LXC P-Channel, N-Channel
On-Resistance
0.5
Ω
LXC P-Channel Current Limit
1200
3050
mA
LXC P-Channel Minimum
Current
100
400
mA
LXC N-Channel Valley Current
880
2450
mA
LXC N-Channel Zero-Crossing
Current
35
175
mA
Maximum Duty Cycle
100
%
Minimum On-Time
150
670
ns
Minimum Off-Time
150
670
ns
REFERENCE
Reference Voltage
V
REF
1.22
1.27
V
Reference Load Regulation
I
REF
= 0 to 50µA
10
mV
Reference Line Regulation
V
CS-
= +2.5V to +5.5V,
I
REF
= 50µA
5
mV
Reference Sink Current
I
REF
10
µA
CVL, CVH REGULATORS
CVL Output Voltage
V
CVL
I
CVL
= 50mA, V
IN
= +2.7V, V
CS-
= 0
2.6
3.1
V
V
IN
= +4V, I
CVH
= 25mA
V
IN
- 2.8
CVH Output Voltage
V
CVH
V
IN
= +12V, I
CVH
= 50mA
V
IN
- 3.7
V
V
CVL
rising
2.40
2.55
CVL Undervoltage Lockout
V
CVL
falling
2.30
2.45
V