Step-Down Controllers with
Synchronous Rectifier for CPU Power
MAX796/MAX797/MAX799
ELECTRICAL CHARACTERISTICS (continued)
(V+ = 15V, GND = PGND = 0V, IVL = IREF = 0A, T
A
= -40°C to +85°C for MAX79_E, unless otherwise noted.) (Note 3)
PARAMETER
+3.3V and +5V STEP-DOWN CONTROLLERS
Input Supply Range
5V Output Voltage (CSL)
3.3V Output Voltage (CSL)
Nominal Adjustable Output
Voltage Range
Feedback Voltage
Line Regulation
Current-Limit Voltage
FLYBACK/PWM CONTROLLER
SECFB Regulation Setpoint
Falling edge, hysteresis = 15mV (MAX796)
Falling edge, hysteresis = 20mV (MAX799)
SHDN
= 2V, 0mA < I
VL
< 25mA, 5.5V < V+ < 30V
Rising edge, hysteresis = 15mV
Rising edge, hysteresis = 25mV
No external load (Note 1)
0µA < I
REF
< 100µA
SHDN
= 0V, V+ = 30V, CSL = 0V or 6V
FB = CSH = CSL = 6V, VL switched over to CSL
1
1
4.8
SYNC = REF
SYNC = 0V or 5V
250
120
250
250
210
SYNC = REF
SYNC = 0V or 5V
High or low
High or low, BST - LX = 4.5V
89
93
91
96
7
7
320
300
150
2.40
-0.08
4.7
3.75
4.2
2.43
2.505
2.60
0.08
5.3
4.05
4.7
2.57
50
10
10
8.4
350
180
V
0mV < (CSH - CSL) < 80mV, FB = VL, 6V < V+ < 30V,
includes line and load regulation
0mV < (CSH - CSL) < 80mV, FB = VL, 4.5V < V+ < 30V,
includes line and load regulation
External resistor divider
(CSH-CSL) = 0V
6V < V+ < 30V
CSH - CSL, positive
CSH - CSL, negative
70
-40
-100
5.0
4.70
3.10
REF
2.40
0.04
5.10
3.35
30
5.40
3.56
6.0
2.60
0.06
130
-160
V
V
V
V
V
%/V
mV
CONDITIONS
MIN
TYP
MAX
UNITS
INTERNAL REGULATOR AND REFERENCE
VL Output Voltage
VL Fault Lockout Voltage
VL/CSL Switchover Voltage
Reference Output Voltage
Reference Load Regulation
V+ Shutdown Current
V+ Off-State Leakage Current
Quiescent Power Consumption
OSCILLATOR AND INPUTS/OUTPUTS
Oscillator Frequency
SYNC High Pulse Width
SYNC Low Pulse Width
Oscillator Sync Range
Maximum Duty Cycle
DL On-Resistance
DH On-Resistance
kHz
ns
ns
kHz
%
Ω
Ω
V
V
V
V
mV
µA
µA
mW
Note 3:
All -40°C to +85°C specifications above are guaranteed by design.
4
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MAXIM [ MAXIM INTEGRATED PRODUCTS ]
