MAX5943AEEE+ Fast Delivery |IC PHOENIX CO.,LIMITED

MAX5943AEEE+ ,FireWire Current Limiter and Low-Drop ORing Switch ControllerApplicationsMAX5943DEEE -40°C to +85°C 16 QSOPFireWire Desktop/Notebook PortMAX5943EEEE -40°C to +8 ..
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MAX5943AEEE+
FireWire Current Limiter and Low-Drop ORing Switch Controller
General Description
The MAX5943 is a fully integrated power-management
IC for FireWire®applications. This device controls two
external power n-channel MOSFETs to regulate current
from the input power supply to the load and performs
low-voltage-drop, power-supply ORing. The MAX5943
operates over a 7.5V to 37V input range and provides
inrush and output current limit in addition to a diode
ORing function suitable for FireWire applications. The
MAX5943 FireWire/IEEE 1394™ protective circuit
(Figure 12) is UL®recognized.
The MAX5943 allows the safe insertion and removal of
FireWire peripherals into a live FireWire port by providing
inrush current control and an output current-limiting func-
tion. The ORing feature provides a very efficient way to
protect the FireWire port when connected to another
FireWire peripheral that sources a higher voltage. By turn-
ing off both external MOSFETS, the MAX5943 provides a
true bidirectional load disconnect. A low-current shut-
down mode disables the MAX5943, resulting in less than
10µA supply current. A pin-selectable input allows
latched or autoretry fault management after a fault.
The MAX5943A features a current-limit function that
actively limits the current drawn by the load with a pro-
grammable timeout. The MAX5943B–MAX5943E do not
actively limit the load current but provide a circuit-breaker
function. See the Selector Guidefor the default and pro-
grammable circuit-breaker timeouts.
The MAX5943 operates over the -40°C to +85°C extended
temperature range and is available in a 16-pin QSOP
package.
Applications
FireWire Desktop/Notebook Port
FireWire Peripheral Device Current Limit
FireWire Hub
Hot Swap
FeaturesProvides Safe Hot Swap for 7.5V to 37V Power
SuppliesUL-Recognized FireWire/IEEE 1394 Protective
CircuitLow-Drop Power ORing with Ultra-Fast Turn-OffProgrammable Active Current Limit (MAX5943A)Programmable Circuit Breaker
(MAX5943B–MAX5943E)±5% Current-Limit Sensing AccuracyProgrammable Current-Limit/Circuit-Breaker
TimeoutFast Current-Limit Response to Output Short-
Circuit Conditions (MAX5943A)Drives External N-Channel Power MOSFETsOvercurrent Fault Status OutputLatched or Autoretry Overcurrent Fault
Management10µA Shutdown CurrentON/OFF Control Allows Undervoltage Lockout
ProgrammingFast Load Disconnect Control Through ON Input
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch ControllerIN
SENSE
GATE1
N.C.
GATE2
OUT
N.C.
GND
TOP VIEW
MAX5943
QSOP
FAULT
TIM
OR_ADJ
ILIM
LATCH
N.C.
ONQ1
Pin Configuration
Ordering Information
19-3378; Rev 2; 10/07
Typical Operating Circuit and Selector Guide appear at end
of data sheet.
FireWire is a registered trademark of Apple Computers, Inc.
IEEE 1394 is a trademark of the Institute of Electrical and
Electronics Engineers trademark.
UL is a registered trademark of Underwriters Laboratories, Inc.
PARTTEMP RANGEPIN-PACKAGE
MAX5943AEEE-40°C to +85°C16 QSOP
MAX5943BEEE-40°C to +85°C16 QSOP
MAX5943CEEE-40°C to +85°C16 QSOP
MAX5943DEEE-40°C to +85°C16 QSOP
MAX5943EEEE-40°C to +85°C16 QSOP
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(VIN= 7.5V to 37V, GND = 0V, and TA= -40°C to +85°C, unless otherwise noted. Typical values are at VIN= 12V, TA= +25°C.)
(Note 1)
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
(Voltages referenced to GND, unless otherwise noted.)
IN............................................................................-0.3V to +80V
OUT........................................................................-0.3V to +80V
SENSE to IN..............................................................-1V to +0.3V
GATE1 to SENSE......................................................-0.3V to +8V
GATE2 to OUT (internally clamped).........................-0.3V to +8V
FAULT.....................................................................-0.3V to +85V
ON, TIM, ILIM, LATCH, OR_ADJ, ONQ1..........-0.3V to (IN + 0.3V)
Continuous Power Dissipation (TA= +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW
Operating Temperature Range...........................-40°C to +85°C
Maximum Junction Temperature.....................................+150°C
Storage Temperature Range.............................-60°C to +150°C
ESD Rating (Human Body Model)......................................2000V
Lead Temperature (soldering, 10s).................................+300°C
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
SUPPLIES
Supply Voltage RangeVIN7.537V
Supply CurrentIINVON = 3V, no load1.32.3mA
Shutdown CurrentISDVON = 0.4V510µA
IN Default Undervoltage LockoutVUVLOVIN rising, ON = IN6.26.56.8V
IN Default Undervoltage Lockout
Hysteresis0.35V
ON Undervoltage Lockout
ThresholdVON_REFVON rising1.201.241.275V
ON Undervoltage Lockout
Threshold Hysteresis70mV
ON Input Bias CurrentION1µA
GATE2 (current-limit/circuit-breaker control)
GATE2 Pullup CurrentIG2U(Note 2)364554µA
7.5V ≤ VIN ≤ 8V4.255.56.5GATE2 High VoltageVG2VGATE2 - VOUT8V ≤ VIN ≤ 37V4.55.56.5V
ILIM = GND47.55052.5
ILIM = floating373941Current-Limit/Circuit-Breaker
Threshold VoltageVTHVIN - VSENSE
ILIM = IN5558.561
ILIM = GND707580
ILIM = floating545964Fast Pulldown Current-Limit
Threshold Voltage (MAX5943A)VTHFVIN - VSENSE (Note 3)
ILIM = IN838893
GATE2 Pulldown Current
(MAX5943A)IG2DVTH < (VIN - VSENSE) < VTHF,
t < tILIM335435535µA
GATE2 Fast Pulldown Current
(MAX5943A)IG2DF(VIN - VSENSE) > VTHF, VGATE2 = VOUT +
4.5V80125200mA
GATE2 Peak Pulldown Current
(MAX5943A)IG2DP(VIN - VSENSE) = 1V1.0A
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
ELECTRICAL CHARACTERISTICS (continued)
(VIN= 7.5V to 37V, GND = 0V, and TA= -40°C to +85°C, unless otherwise noted. Typical values are at VIN= 12V, TA= +25°C.)
(Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
GATE2 Pulldown Current During
Any GATE2 Turn-Off ConditionIG2OFFVGATE2 = VOUT + 4.5V (Note 4)80125200mA
GATE1 (ORing control)
OR_ADJ = GND357
OR_ADJ = floating5.57.59.5ORing Switch Turn-On Current
Threshold VoltageVOR(VIN - VSENSE) rising
OR_ADJ = IN8.510.512.8
ORing Switch Turn-On Current
Threshold Voltage Hysteresis(VIN - VSENSE) falling0.5mV
GATE1 Pullup CurrentIG1U(Note 5)364554µA
7.5V ≤ VIN ≤ 8V4.255.56.5GATE1 High VoltageVG1VGATE1 - VSENSE8V ≤ VIN ≤ 37V4.55.56.5V
GATE1 Turn-Off Switch On-
ResistanceRG1Measured between GATE1 and SENSE
when (VIN - VSENSE) < VOR23Ω
LOGIC INPUTS
IIXCurrent into or out of input for tri-state logic
condition-3+3
IIXLCurrent out of input for logic low20
ILIM, OR_ADJ Input-Logic
Tristate Current Tolerance
(Note 6)IIHCurrent into input for logic high20
VILVON > VON_REF0.7VLATCH, ONQ1 Input-Logic Low
VoltageIILLATCH, ONQ1 = GND, VON > VON_REF1µA
LATCH, ONQ1 Input-Logic High
VoltageVIHVON > VON_REF1.8V
LATCH, ONQ1 Input CurrentIIHAll voltages = VIN, VON > VON_REF1µA
TIM, ILIM, LATCH, OR_ADJ,
OUT, ONQ1 Shutdown Mode
Input Current
IIH_SDAll voltages = VIN, VON ≤ 0.4V1µA
FAULT Output Low VoltageVOLLow-impedance state, I FAULT = 5mA0.120.25V
FAULT Output High Leakage
CurrentIOHHigh-impedance state, V FAULT = 37V1µA
TIMING
TIM = IN1.782.022.26ms
RTIM = 4kΩ0.871.041.21ms
RTIM = 50kΩ9.211.0512.9ms
Current-Limit Timeout
(MAX5943A)tILIMCurrent-limit mode
(Note 7)
TIM = floating120175225ms
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
ELECTRICAL CHARACTERISTICS (continued)
(VIN= 7.5V to 37V, GND = 0V, and TA= -40°C to +85°C, unless otherwise noted. Typical values are at VIN= 12V, TA= +25°C.)
(Note 1)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
TIM = IN or
TIM ≥ 3.4V0.450.510.57ms
RTIM = 4kΩ2732.538µs
RTIM = 50kΩ228345403µs
Circuit-breaker mode,
MAX5943B
TIM = floating3.755.57ms
TIM = IN or
TIM ≥ 3.4V0.891.001.13ms
RTIM = 4kΩ546576µs
RTIM = 50kΩ575690806µs
Circuit-breaker mode,
MAX5943C
TIM = floating7.510.914ms
TIM = IN1.782.022.26ms
RTIM = 4kΩ109130151µs
RTIM = 50kΩ1.151.381.61ms
Circuit-breaker mode,
MAX5943D
TIM = floating1521.928ms
TIM = IN or
TIM ≥ 3.4V3.564.054.52ms
RTIM = 4kΩ217260303µs
RTIM = 50kΩ2.32.763.23ms
Circuit-Breaker Timeout
(MAX5943B–MAX5943E) (Note 7)tCB
Circuit-breaker mode,
MAX5943E
TIM = floating304456ms
Automatic Restart Delay After
Current-Limit/Circuit-Breaker
Timeout
tOFFLATCH = GND (Note 8)
128 x
(tILIM
OR tCB)
GATE1 Turn-Off Time
(ORing Response Time)tORFrom VOR trigger until (VGATE1 - VIN) < 1V,
CGATE1 = 10nF100ns
Turn-Off Response TimetON_OFF
Time from VON < (VON_OFF - Hysteresis)
until (VGATE2 - VOUT) < 1V, GATE2 = open
(Note 9)
0.340.6µs
Minimum Delay from ON Low to
Low-Current Shutdown ModetSDON step from 1.3V to 0.4V50µs
Note 1:All min/max parameters are tested at +25°C and +85°C. Limits at -40°C are guaranteed by design.
Note 2:Measured at both VGATE2= VOUT= 0V and VGATE2= VOUT= VIN.
Note 3:The typical value of parameter VTHFis 1.5 x VTH.
Note 4:Current-Limit/Circuit-Breaker Timeout; IN or ON low.
Note 5:See the Typical Operating Circuit. Measured at VGATE1= VSENSE.
Note 6:The tristate (“floating”) logic condition will be entered if the pin current is within these limits.
Note 7:RTIMis connected from TIM to GND. The maximum timeout period is enforced to prevent arbitrarily long operation in cur-
rent-limit mode. Therefore, the relationship between resistor value and timeout changes for large values of RTIM. See
Current-Limit Timeout vs. RTIM in the Typical Operating Characteristicsfor nominal values.
Note 8:Parameter tOFFis a direct multiple of tILIM(or tCB), so the limits for tOFFtrack the limits for tILIM (or tCB).
Note 9:If the ON voltage goes below VON_REF- Hysteresis, then GATE2 goes low immediately to disconnect power from the load
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX5943 toc01
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)3020251510
TA = +85°C
TA = +25°C
TA = -40°C
SHUTDOWN SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX5943 toc02
SUPPLY VOLTAGE (V)
SHUTDOWN SUPPLY CURRENT (3020251510
CURRENT-LIMIT/CIRCUIT-BREAKER
THRESHOLD VOLTAGE vs. TEMPERATURE
MAX5943 toc03
TEMPERATURE (°C)
THRESHOLD VOLTAGE (mV)3510-15
ILIM = GND
VIN = 32V
VIN = 12V
VIN = 7.5V
CURRENT-LIMIT/CIRCUIT-BREAKER
THRESHOLD VOLTAGE vs. TEMPERATURE
MAX5943 toc04
TEMPERATURE (°C)
THRESHOLD VOLTAGE (mV)3510-15
ILIM = IN
VIN = 32V
VIN = 12V
VIN = 7.5V
CURRENT-LIMIT/CIRCUIT-BREAKER
THRESHOLD VOLTAGE vs. TEMPERATURE
MAX5943 toc05
TEMPERATURE (°C)
THRESHOLD VOLTAGE (mV)3510-15
ILIM = FLOATING
TIMEOUT PERIOD vs. RTIM
MAX5943 toc06
RTIM (kΩ)
TIMEOUT PERIOD (
MAX5943A
MAX5943E
ORing THRESHOLD VOLTAGE
vs. TEMPERATURE
MAX5943 toc07
TEMPERATURE (°C)
ORing THRESHOLD VOLTAGE (mV)35-1510
OR_ADJ = IN
OR_ADJ = OPEN
OR_ADJ = GND
GATE CURRENTS vs. TEMPERATURE
MAX5943 toc08
TEMPERATURE (°C)
GATE CURRENTS (3510-15-4085
GATE2
GATE1
GATE1 DRIVE VOLTAGE
vs. TEMPERATURE
MAX5943 toc09
TEMPERATURE (°C)
GATE1 DRIVE VOLTAGE (V)3510-15
Typical Operating Characteristics
(VIN= +12V, TA= +25°C, unless otherwise noted.)
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
Typical Operating Characteristics (continued)
(VIN= +12V, TA= +25°C, unless otherwise noted.)
GATE2 DRIVE VOLTAGE
vs. TEMPERATURE
MAX5943 toc10
TEMPERATURE (°C)
GATE2 DRIVE VOLTAGE (V)3510-15
ON HIGH VOLTAGE vs. TEMPERATURE
MAX5943 toc11
TEMPERATURE (°C)
ON HIGH VOLTAGE (V)3510-15
ON LOW VOLTAGE vs. TEMPERATURE
MAX5943 toc12
TEMPERATURE (°C)
ON LOW VOLTAGE (V)3510-15-4085
FAULT LOW VOLTAGE
vs. TEMPERATURE
MAX5943 toc13
TEMPERATURE (°C)
FAULT LOW VOLTAGE (mV)3510-15-4085
IFAULT = 5mA
ORing THRESHOLD RESPONSE TIME
MAX5943 toc14
IIN
500mA/div
VOUT
5V/div
(VGATE - VSENSE)
5V/div
VIN
10V/div
100μs/div
OR_ADJ = IN
TURN-OFF RESPONSE TIME
MAX5943 toc15
IIN
1A/div
VOUT
10V/div
VGATE2
10V/div
VON
2V/div
200ns/div
MAX5943A SHORT-CIRCUIT EVENT
(VIN = 37V)
MAX5943 toc16
IIN
1A/div
VOUT
50V/div
VGATE2
50V/div
VIN
50V/div
400μs/div
TIM = IN
ILIM = GND
VFAULT
50V/div
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
MAX5943A SHORT-CIRCUIT EVENT
(VIN = 37V)
MAX5943 toc17
IIN
10A/div
VOUT
50V/div
VGATE2
50V/div
VIN
50V/div
100ns/div
ILIM = GND
VFAULT
50V/div
MAX5943A SHORT-CIRCUIT RESPONSE
(VIN = 8V)
MAX5943 toc18
IIN
1A/div
VOUT
10V/div
VGATE2
10V/div
VIN
10V/div
400μs/div
TIM = INVFAULT
10V/div
MAX5943A SHORT-CIRCUIT RESPONSE
(VIN = 8V)
MAX5943 toc19
IIN
10A/div
VOUT
10V/div
VGATE2
10V/div
VIN
10V/div
100ns/div
VFAULT
10V/div
MAX5943E SHORT-CIRCUIT RESPONSE
(VIN = 24V)
MAX5943 toc20
IIN
166A/div
VOUT
50V/div
VGATE2
50V/div
VIN
50V/div
200μs/div
VFAULT
50V/div
MAX5943E SHORT-CIRCUIT RESPONSE
(VIN = 8V)
MAX5943 toc21
IIN
60A/div
VOUT
10V/div
VGATE2
10V/div
VIN
10V/div
100μs/div
VFAULT
10V/divTIM = IN
ORing SWITCHOVER WAVEFORM
MAX5943 toc22
IIN1
500mA/div
VOUT
1V/div
200μs/div
IIN2
500mA/div
VIN1 = 12VVON2 RISING = 12V
VIN2 = 128VCOUT = 0
Typical Operating Characteristics (continued)
(VIN= +12V, TA= +25°C, unless otherwise noted.)
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
ORing SWITCHOVER WAVEFORM
(VIN2 RISING ABOVE VIN1)
MAX5943 toc23
IIN1
500mA/div
VOUT
1V/div
10μs/div
IIN2
500mA/div
VIN1 = 12VVON2 RISING = 12V
VIN2 = 13VCOUT = 0
ORing SWITCHOVER WAVEFORM
(VIN2 FALLING BELOW VIN1)
MAX5943 toc24
IIN1
500mA/div
VOUT
1V/div
20μs/div
IIN2
500mA/div
VIN1 = 12VVON2 FALLING = 12V
VIN2 = 13VCOUT = 0
MAX5943A HOT PLUG-IN LOAD CAPACITANCE
INTO ACTIVE PORT (NO FAULT)
MAX5943 toc25
IIN
2A/div
VFAULT
10V/div
400μs/div
VOUT
10V/div
CLOAD = 220μF
TIM = IN
VGATE2
10V/div
MAX5943A HOT PLUG-IN LOAD CAPACITANCE
INTO ACTIVE PORT (CURRENT-LIMIT TIMEOUT)
MAX5943 toc26
IIN
1A/div
VFAULT
10V/div
400μs/div
VOUT
10V/div
CLOAD = 470μF
TIM = IN
VGATE2
10V/div
Typical Operating Characteristics (continued)
(VIN= +12V, TA= +25°C, unless otherwise noted.)
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
Pin Description
PINNAMEFUNCTION
1ON
On/Off-Control Input. ON sets the undervoltage lockout threshold and resets the part after a fault latch.
Drive ON high to enable the device. Drive ON low to disable the device. Connect ON to IN for the default
undervoltage lockout threshold. Connect a resistor-divider from IN to ON and GND to program the desired
undervoltage lockout threshold.FAULTCurrent-Fault, Active-Low, Open-Drain Output. FAULT asserts and latches low after a current-limit/circuit-
breaker fault has exceeded the current-limit/circuit-breaker timeout period (see the FAULT section).TIMCurrent-Limit/Circuit-Breaker Timeout Adjustment Input. Connect TIM to IN for the default timeout period or
connect a resistor from TIM to GND to program the current-limit/circuit-breaker timeout period.ILIM
Current-Limit/Circuit-Breaker Threshold Input. Leave ILIM open for a 40mV circuit-breaker threshold,
connect to GND for a 50mV circuit-breaker threshold, or connect to IN for a 60mV circuit-breaker threshold
(see the Current Limiting section).LATCH
Latch or Autoretry Fault Management Selection Input. Connect LATCH to IN to select latch-off mode
after a current-limit/circuit-breaker timeout. Connect LATCH to GND for autorestart mode after a current-
limit/circuit-breaker timeout.OR_ADJ
ORing Switch Turn-On Current Threshold Adjustment Input. Select one of three ORing switch turn-on
threshold settings: connect OR_ADJ to GND, connect OR_ADJ to IN, or leave OR_ADJ floating (see the
Power-Supply ORing section).
7, 10, 13N.C.No Connection. Not internally connected.ONQ1
ORing Switch Manual Turn-On Input. Drive ONQ1 low to enable power-supply ORing. Drive ONQ1 high
to set GATE1 high to allow reverse current flow. ONQ1 is disabled when VIN is below the UVLO threshold,
VON is below the VON_REF threshold, and after a current/circuit-breaker fault.GNDGroundOUTOutput Voltage Sense. Connect to the output.GATE2
Current-Limiter Switch Gate Drive Output. Connect GATE2 to the gate of the 2nd n-channel MOSFET.
GATE2 is a charge pump with a 45µA pullup current to 5.5V (typ) above OUT when active (see the Typical
Operating Circuit).GATE1
ORing Switch Gate-Drive Output. Connect GATE1 to the gate of the 1st n-channel MOSFET. GATE1 is a
charge pump with a 45µA pullup current to 5.5V (typ) above SENSE when active (see the Typical
Operating Circuit).SENSECurrent-Sense Negative Input. Connect a current-sense resistor, RSENSE, from IN to SENSE (see the
Typical Operating Circuit).INInput Power and Current-Sense Positive Input. Connect IN to the positive terminal of the current-sense
resistor and to the power source (see the Typical Operating Circuit).
MAX5943
FireWire Current Limiter and Low-Drop
ORing Switch Controller
Detailed Description
The MAX5943 performs hot-swapping, power-supply
ORing, and current limiting for FireWire power-supply
applications. The MAX5943 incorporates two MOSFET
drivers (GATE1 and GATE2) to control two external
n-channel power MOSFETs to perform low-voltage-drop
power-supply ORing (GATE1) and hot swapping and
current limiting (GATE2) from the input power supply to
the load. A sense resistor provides accurate current-
limiting/circuit-breaker function. GATE1 and GATE2
provide true load disconnect to prevent current flowing
from either direction between IN and OUT.
The MAX5943 remains in low-current shutdown mode
when VONis below the 0.4V threshold. Low-current
shutdown mode disables the MAX5943, resulting in
less than 10µA supply current. Shutdown places all
logic inputs in a high-impedance state allowing the
inputs to be connected to IN without drawing additional
current from the supply.
When the input supply voltage (VIN) is above 7.5V and
VONis above the VON_REF threshold, the MAX5943
turns on, sourcing 45µA current from GATE2 (current
regulation) to enhance Q2 slowly. For the MAX5943A, if
the voltage across the current-sense resistor, VIS, is
greater than the programmed current-limit threshold,
the MAX5943A regulates the GATE2 voltage to limit the
load current at the current-limit level so that VISis equal
to VTH. In normal operation, VISdrops below VTHand
GATE2 rises to approximately 5.5V above OUT. Since
the MAX5943B–MAX5943E do not regulate the load
current, a capacitor can be added from GATE2 to GND
to limit inrush current during startup (see the
Applications Informationsection).
SENSE
SENSEGATE1
6.5V
1.24V
GATE1GATE2OUT
MAX5943A–MAX5943E
POWER
SOURCE
(FAST CURRENT-
LIMIT
THRESHOLD)
CIRCUIT-BREAKER
(CURRENT-LIMIT)
THRESHOLD
COMPARATOR
THRESHOLD
GND
LATCH
TIM
X128
FAULT
0.4V
SHUTDOWN
MODE
ON COMPARATOR
( ) MAX5943A ONLY.
UVLO COMPARATOR
FAULT
MANAGEMENT
LATCH OR
AUTORETRY
AUTORETRY
TIMEOUT
PERIOD
FAULT
TIMEOUT
GATE1
DRIVE
CP1CP2
GATE
CHARGE
PUMPS
OUTGATE2
GATE2
DRIVE
ONQ1
OR_ADJ
ILIM
RSENSEQ1Q2
Figure 1. MAX5943 Functional Diagram

Partno	Mfg	Dc	Qty	Available	Descript
MAX5943AEEE+ \|MAX5943AEEE	MAXIM	N/a	54	avai	FireWire Current Limiter and Low-Drop ORing Switch Controller