MAX1566-MAX1567 Datasheet, PDF (8/35 Pages) Maxim Integrated Products – Six-Channel, High-Efficiency, Digital Camera Power Supplies

Six-Channel, High-Efficiency, Digital
Camera Power Supplies
ELECTRICAL CHARACTERISTICS (continued)
(V_PVSU = V_PV = V_PVM = V_PVSD = V_INDL2 = 3.6V, T_A = -40°C to +85°C, unless otherwise noted.)
PARAMETER
CONDITIONS
MIN
AUX3 FBL or FBH to CC
35
Transconductance
FB_ Input Leakage Current
DL_ Driver Resistance
AUX1OK Output Low
AUX1OK Leakage Current
OVERLOAD PROTECTION
SCF Leakage Current
SCF Output Low Voltage
LOGIC INPUTS (ON_, SUSD)
ONSU Input Low Level
ONSU Input High Level
Output high or low
0.1mA into AUX1OK
ONSU = GND
ONSU = PVSU, FBSU = 1.5V
0.1mA into SCF
1.1V < PVSU < 1.8V
1.8V ≤ PVSU < 2.5V
2.5V ≤ PVSU < 5.5V
1.1V < PVSU < 1.8V
1.8V < PVSU < 5.5V
-100
(PVSU
- 0.2)
1.6
MAX UNITS
150
µS
+100
nA
7
Ω
0.1
V
1
µA
1
µA
0.1
V
0.2
0.4
V
0.5
V
ONM, ONSD, ON1, ON2, ON3,
SUSD Input Low Level
ONM, ONSD, ON1, ON2, ON3,
SUSD Input High Level
SUSD Input Leakage
2.7V < PVSU < 5.5V (Note 8)
2.7V < PVSU < 5.5V (Note 8)
0.5
V
1.6
V
1
µA
Note 2: The MAX1566/MAX1567 are powered from the step-up output (PVSU). An internal low-voltage startup oscillator drives the
step-up starting at approximately 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 current is limited.
Note 3: Since the device is powered from PVSU, a Schottky rectifier, connected from the battery to PVSU, is required for low-voltage
startup.
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 AUX1OK, SDOK,
and SCF Connections section.
Note 5: The step-up current limit in startup refers to the LXSU switch current limit, not the output current limit.
Note 6: If the main converter is configured as a step-up (SUSD = PVSU), the P-channel synchronous rectifier is disabled until the
2.5V normal operation threshold has been exceeded. If the main converter is configured as a step-down (SUSD = GND), all
step-down operation is locked out until the normal operation threshold has been exceeded. When the main is configured as
a step-down, operation in dropout (100% duty cycle) can only be maintained for 100,000 OSC cycles before the output is
considered faulted, triggering global shutdown.
Note 7: Operation in dropout (100% duty cycle) can only be maintained for 100,000 OSC cycles before the output is considered
faulted, triggering global shutdown.
Note 8: ONM, ONSD, ON1, ON2, and ON3 are disabled until 1024 OSC cycles after PVSU reaches 2.7V.
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