Step-Down Controllers with
Synchronous Rectifier for CPU Power
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, GND = PGND = 0V, I VL = I REF = 0A, T
A
= 0°C to +70°C for MAX79_C, T
A
= 0°C to +85°C for MAX79_E,
T
A
= -55°C to +125°C for MAX79_M, unless otherwise noted.)
PARAMETER
Reference Output Voltage
Reference Fault Lockout Voltage
Reference Load Regulation
CSL Shutdown Leakage Current
V+ Shutdown Current
V+ Off-State Leakage Current
Dropout Power Consumption
Quiescent Power Consumption
CONDITIONS
No external load (Note 1)
Falling edge
0µA < I
REF
< 100µA
SHDN = 0V, CSL = 6V, V+ = 0V or 30V, VL = 0V
SHDN = 0V, V+ = 30V,
CSL = 0V or 6V
FB = CSH = CSL = 6V,
VL switched over to CSL
V+ = 4V, CSL = 0V (Note 2)
CSH = CSL = 6V
SYNC = REF
SYNC = 0V or 5V
270
125
200
200
Guaranteed by design
190
SYNC = REF
SYNC = 0V or 5V
SYNC
SHDN, SKIP
SYNC
SHDN, SKIP
SHDN, 0V or 30V
SECFB, 0V or 4V
Input Current
SYNC, SKIP
CSH, CSL, CSH = CSL = 6V, device not shut down
FB, FB = REF
DL Sink/Source Current
DH Sink/Source Current
DL On-Resistance
DH On-Resistance
DL forced to 2V
DH forced to 2V, BST-LX = 4.5V
High or low
High or low, BST-LX = 4.5V
1
1
7
7
89
93
VL - 0.5
2.0
0.8
0.5
2.0
0.1
1.0
50
±100
nA
A
A
Ω
Ω
µA
91
96
200
340
MAX79_C
MAX79_E/M
MAX79_C
MAX79_E/M
0.1
1
1
1
1
4
4.8
300
150
MAX79_C
MAX79_E/M
MIN
2.46
2.45
1.8
TYP
2.505
MAX
2.54
2.55
2.3
50
1
3
5
3
5
8
6.6
330
175
UNITS
V
V
mV
µA
µA
µA
mW
mW
MAX796/MAX797/MAX799
OSCILLATOR AND INPUTS/OUTPUTS
Oscillator Frequency
SYNC High Pulse Width
SYNC Low Pulse Width
SYNC Rise/Fall Time
Oscillator Sync Range
Maximum Duty Cycle
Input High Voltage
Input Low Voltage
kHz
ns
ns
ns
kHz
%
V
V
Note 1:
Since the reference uses VL as its supply, V+ line-regulation error is insignificant.
Note 2:
At very low input voltages, quiescent supply current may increase due to excess PNP base current in the VL linear
regulator. This occurs only if V+ falls below the preset VL regulation point (5V nominal). See the Quiescent Supply Current
vs. Supply Voltage graph in the
Typical Operating Characteristics.
_______________________________________________________________________________________
3
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
