HV301/HV311
Hot Swap Controller
(Negative Supply Rail)
Features
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±10V to ±90V Operation
Built-in “normally on” turn-on clamp eliminates components
UV/OV Lock Out & Power-on-Reset for Debouncing
Sense resistor program ground circuit breaker
Programmable circuit breaker holdoff
Inrush control using either: i) servo or ii) feedback cap
Feedback to Ramp pin means no Gate clamp needed
Application solution for input voltage step (diode “ORing”)
Programmable Auto-Retry (tens of seconds if desired)
Auto-Retry or Latched Operation
Enable through Open Drain interface to UV or OV
Low Power, <0.6mA PWRGD Flag Operation, <0.4mA
Sleep Mode
Small SOIC-8 Package
HV301/HV311
Ordering Information
A c t i v e St at e o f
Po w er Go o d Si g n al
HIGH
LOW
Pac k ag e Op t i o n s
8 Pin SO
HV301LG
HV311LG
Applications
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Typical Application Circuit
GND
8
VDD
PWRGD / PWRGD
R1
487kΩ
R2
6.81kΩ
R3
9.76kΩ
VEE
4
SENSE
5
GATE
6
C1
10nF
-48V
R4
12.5mΩ
Q1
IRF530
-48V
RAMP
7
C2
1
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General Description
The Supertex HV301 and HV311 Hot Swap Controllers provide
control of power supply connection during insertion of cards or
modules into live backplanes. They may be used in systems
where active control is implemented in the negative lead of
supplies ranging from ±10V to ±90V.
-48V Central Office Switching
-24V Cellular and Fixed Wireless Systems
-24V PBX Systems
Line Cards
-48V Powered Ethernet for VoIP
Distributed Power Systems
Power Supply Control
+48V Storage Networks
Electronic Circuit Breaker
During initial power application the gate of the external pass
device is clamped low to suppress contact bounce glitches by a
“normally on” circuit which does not require initialization of the
IC. Thereafter the UV/OV supervisors and power-on-reset work
together to suppress gate turn on until mechanical bounce has
ended. The HV301/311 then control the current inrush limit to a
programmed level using one of two possible methods, i) servo
control or ii) a drain to ramp capacitor. The above methods
eliminate the need for extra hold-off or current limiting compo-
nents. The devices also include an electronic circuit breaker,
programmed by a sense resistor.
After the load capacitance has fully charged, the HV301/311 will
transition into a low power mode, and enable the open drain
PWRGD. In low power mode the HV301/311 continues to moni-
tor the input voltage and monitor the current level. If a load fault
occurs, the electronic circuit breaker will trip, the pass
element will be turned off, and the PWRGD will return to an
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ENABLE / ENABLE
UV
+5V
Waveforms
Drain
50V/div
V
IN
50V/div
2
OV
HV301/
HV311
Cload
DC/DC
PWM
CONVERTER
COM
0.85nF
Gate
5.00V/div
I
inrush
500mA/div
NOTES: 1.
2.
3.
4.
Undervoltage Shutdown (UV) set to 35V.
Overvoltage Shutdown (OV) set to 65V.
Current Limit set to ~1A.
CB set to 8A.
5.00ms/div
A092605
A092605
1
SUPERTEX [ Supertex, Inc ]
