MAX4370ESA+ Maxim Integrated Products, MAX4370ESA+ Datasheet - Page 13

• Manufacturer Part Number: MAX4370ESA+
• Description: IC CNTRLR HOT-SWAP 8-SOIC
• Manufacturer: Maxim Integrated Products
• Type: Hot-Swap Controllerr

Specifications of MAX4370ESA+

• Applications: General Purpose
• Internal Switch(s): No
• Voltage - Supply: 2.7 V ~ 13.2 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (0.154", 3.90mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 8. Slow Comparator Response Time vs. C
The actual turn-on time is determined by the longer of
the two timings of Case A and Case B. Set the start-up
timer (t
time for the output voltage to settle; also take into con-
sideration device parameter variation.
The slow comparator threshold is set at 50mV, and its
response time is determined by the external capacitor
connected to CSPD (Figure 8).
A minimum response time of 20µs (typ) is achieved by
leaving this pin floating. This time is determined inter
nally and is not affected by stray capacitance at CSPD
(up to 100pF).
Set the slow comparator response time to be longer
than the normal operation load transients.
The ON/OFF function of the MAX4370 is controlled by
the ON comparator. This is a precision voltage com
parator that can be used for temperature monitoring
(Figure 9) or as an additional undervoltage lockout. The
comparator threshold voltage is set at 0.6V with a 3mV
typical hysteresis.
The ON comparator initiates start-up when its input volt-
age (V
off the MOSFET when the voltage falls below the
threshold. The ON comparator is also used to reset the
MAX4370 after a fault condition.
The ON comparator input and the STAT output can be
pulled to voltages up to 14V independently of V
ON
START
Current-Regulating Hot-Swap Controller with
1000
) rises above the threshold voltage, and turns
0.01
100
0.1
10
1
0.01
Slow Comparator Response Time (C
) at 2 · t
t
CSPD
______________________________________________________________________________________
0.1
(ms) = 0.2
ON
or longer to guarantee enough
·
1
C
C
SPD
SPD
(nF)
(nF)
DualSpeed/BiLevel Fault Protection
10
ON Comparator
100
1000
SPD
IN
.
SPD
)
-
-
In some applications, it is useful to use connectors with
staggered leads. In Figure 10, the ON pin forces the
removable board to be powered up only when all con-
nections are made.
Figure 9. Temperature Monitoring and Protection
Figure 10. Fail-Safe Connector
RESET
NTC
V
CC
V
R1 = R2
R2 = VALUE OF THE NTC RESISTOR AT THE LIMIT TEMPERATURE
V
REF
REF
R1
= ANY REFERENCE VOLTAGE AVAILABLE OR V
BACKPLANE
R2
·
ON
(V
REF
/ O.6 - 1)
0.6V
REMOVABLE
CARD
1M
10k
ON
V
IN
MAX4370
IN
VSEN GATE
CONTROL
LOGIC
13