Rainbow Electronics MAX1585 User Manual
Page 6
MAX1584/MAX1585
5-Channel Slim DSC Power Supplies
6
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PARAMETER
CONDITIONS
MIN
MAX
UNITS
FBSD Regulation Voltage
1.225
1.275
V
FBSD to CCSD
Transconductance
FBSD = CCSD
80
185
µS
FBSD Input Leakage Current
FBSD = 1.25V
-100
+100
nA
LXSD Leakage Current
V
LXSD
= 0 to 3.6V, PVSU = 3.6V
5
µA
N channel
150
Switch On-Resistance
P channel
250
m
Ω
P-Channel Current Limit
0.65
0.95
A
SDOK Output Low Voltage
0.1mA into
SDOK
0.1
V
SDOK Leakage Current
ONSU = GND
1
µA
AUX1, 2, 3 DC-DC CONTROLLERS
Maximum Duty Cycle
FB_ = 1V
80
90
%
FB1 and FB3 Regulation Voltage
FB_ = CC_
1.225
1.275
V
FB2 (MAX1584) Regulation
Voltage
FB_ = CC_
1.225
1.275
V
FB2 (MAX1585) (Inverter)
Regulation Voltage
FB_ = CC_
-0.01
+0.01
V
FB_ to CC_ Transconductance
FB_ = CC_
80
185
µS
FB_ Input Leakage Current
FB_ = 1.25V
-100
+100
nA
DL_ Driver Resistance
Output high or low
10
Ω
AUX1OK Output Low Voltage
0.1mA into
AUX1OK
0.1
V
AUX1OK Leakage Current
ONSU = GND
1
µA
OVERLOAD AND THERMAL PROTECTION
SCF Leakage Current
ONSU = PVSU, FBSU = 1.5V
1
µA
SCF Output Low Voltage
0.1mA into SCF
0.1
V
LOGIC INPUTS
1.1V < PVSU < 1.8V (ONSU only)
0.2
ON_ Input Low Level
1.8V < PVSU < 5.5V
0.4
V
1.1V < PVSU < 1.8V (ONSU only)
V
PVSU
- 0.2
ON_ Input High Level
1.8V < PVSU < 5.5V
1.6
V
ELECTRICAL CHARACTERISTICS (continued)
(V
PVSU
= V
PV
= V
PVSD
= V
INDL2
= 3.6V, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 8)
Note 2: The MAX1584/MAX1585 are powered from the step-up output (PVSU). An internal low-voltage startup oscillator drives the
step-up starting at about 0.9V until PVSU reaches approximately 2.5V. When PVSU reaches 2.5V, the main control circuitry
takes over. Once the step-up is up and running, it can maintain operation with very low input voltages; however, output cur-
rent is limited.
Note 3: Since the device is powered from PVSU, a Schottky rectifier, connected from the input battery to PVSU, is required for low-
voltage startup, or if PVSD is connected to V
IN
instead of PVSU.
Note 4: The step-up regulator is in startup mode until this voltage is reached. Do not apply full load current during startup. A power-
OK output can be used with an external PFET to gate the load until the step-up is in regulation. See the Applications
Information section.