MAX5944 MAXIM [Maxim Integrated Products], MAX5944 Datasheet - Page 14

• Manufacturer Part Number: MAX5944
• Description: Dual FireWire Current Limiter and Low-Drop ORing
• Manufacturer: MAXIM [Maxim Integrated Products]

Dual FireWire Current Limiter and Low-Drop
ORing Switch Controller
Figure 9. Two-Port FireWire Power Provider
14
______________________________________________________________________________________
BATTERY-POWER
POWER SOURCE
SOURCE
SOURCE
POWER
CABLE
POWER OUT
CABLE
ON
PHY
SLEEP
NOT
ONA
ONQ1
GND
ONB
ONA
ONQ1
GND
ONB
INB
INA
FAULTA
FAULTB
15mΩ
15mΩ
SENSEB GATE1B
SENSEA GATE1A
MAX5944
INB
INA
IRF7478
IRF7478
R
R
FB
BST
LX
SENSEA
SENSEB
MAX5944
GND
MAX5035
SENSEB GATE1B
SENSEA GATE1A
IRF7478
GATE2B OUTB
IRF7478
GATE2A OUTA
SGND
FAULTA
FAULTB
Q1A
Q1B
V
ON
CURRENT-LIMIT
VD
IN
SENSE
GATE2B OUTB
GATE2A OUTA
Q2A
Q2B
IN4148
TRANSISTOR COUNT: 4,648
PROCESS: BiCMOS
ONA
ONQ1
GND
ONB
VERY-LOW-DROP
POWER SOURCE
INB
ORing DIODE
INA
IN4148
TO FireWire
PORT 0
TO FireWire
PORT 1
30mΩ
30mΩ
SENSEB GATE1B
SENSEA GATE1A
Typical Operating Circuit
MAX5944
IRF7478
IRF7478
CURRENT-LIMIT/
CIRCUIT-BREAKER
AND INRUSH CONTROL
EQUIVALENT CIRCUIT
IRF7478
GATE2B OUTB
IRF7478
GATE2A OUTA
FAULTA
FAULTB
Chip Information
IN4148
IN4148
PORT 1
SENSE
PORT 0
SENSE
LOAD DISCONECT
SWITCH
CPA SENSE
TO FireWire
PORT 0
TO FireWire
PORT 1
PORT 0
PORT 1