MAX5903 MAXIM [Maxim Integrated Products], MAX5903 Datasheet - Page 6

• Manufacturer Part Number: MAX5903
• Description: +72V SOT23 Simple Swapper Hot-Swap Controllers
• Manufacturer: MAXIM [Maxim Integrated Products]

necting the load immediately. If no circuit breaker fault
exists, the MAX5902/MAX5903 assert the power-good
output. Then, if any of four conditions exist, the power
good output deasserts and the MAX5902/MAX5903
turn off the MOSFET. The four conditions are: the volt-
age across the MOSFET exceeds the circuit breaker
threshold; the supply voltage falls below the undervolt-
age lockout level; the die temperature exceeds
+125°C; or ON/OFF is forced low. After a circuit break-
er fault, the MAX5902L/MAX5903L keep the MOSFET
off until the power is cycled, or the part is reset by tog-
gling ON/OFF low for 10ms (typ). After a circuit breaker
fault, the MAX5902A/MAX5903A automatically restarts
in 150ms (typ). All versions automatically restart after a
+72V SOT23 Simple Swapper Hot-Swap
Controllers
6
Figure 2. Test Circuits
_______________________________________________________________________________________
V
V
IN
IN
V
IN
V
V
V
(a) SUPPLY CURRENT
(b) V
(b) GATE DRIVE VOLTAGE
UVLO
I
ON/OFF
ON/OFF
ON/OFF
V
V
V
S
S
S
MAX5902
MAX5902
MAX5902
GATE DRAIN
GND
GATE DRAIN
GND
GATE DRAIN
GND
PGOOD
PGOOD
PGOOD
50kΩ
V
V
48V
thermal fault, or an undervoltage shutdown, if the fault
condition goes away for at least 150ms (typ).
ON/OFF offers external control of the MAX5902/
MAX5903, facilitating power-supply sequencing, and
may also be used to change the undervoltage lockout
(UVL) level. UVLO keeps the external MOSFET
switched off as long as the input voltage is below the
desired level.
A power good output, PGOOD (MAX5902) or PGOOD
(MAX5903), asserts when the external MOSFET is fully
enhanced and the source-drain voltage is below the
circuit breaker threshold. PGOOD and PGOOD are
open-drain outputs referenced to GND, and can with-
stand up to +72V.
48V
48V
ON/OFF
ON/OFF
ON/OFF
V
V
V
S
S
S
50kΩ
MAX5902A
(d) RETRY TIMEOUT
(d) STARTUP WAVEFORMS
(d) CIRCUIT BREAKER EVENT
MAX5902
MAX5902
GATE
50Ω
GATE
GND
GND
IRFR5410
GATE
GND
PGOOD
PGOOD
PGOOD
DRAIN
DRAIN
DRAIN
50kΩ
0 TO 0.5V
R
L
SCOPE
SCOPE
SCOPE
C
L
SCOPE
SCOPE
SCOPE
SCOPE
SCOPE
SCOPE