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HV301/HV311

08/26/02

Supertex Inc. does not recommend the use of its products in life support applications and will not knowingly sell its products for use in such applications unless it receives an adequate "products liability

indemnification insurance agreement." Supertex does not assume responsibility for use of devices described and limits its liability to the replacement of devices determined to be defective due to

workmanship. No responsibility is assumed for possible omissions or inaccuracies. Circuitry and specifications are subject to change without notice. For the latest product specifications, refer to the

Supertex website: http://www.supertex.com. For complete liability information on all Supertex products, refer to the most current databook or to the Legal/Disclaimer page on the Supertex website.

Features

❑

±10V to ±90V Operation

❑

Built-in “normally on” turn-on clamp eliminates components

❑

UV/OV Lock Out & Power-on-Reset(POR) for Debouncing

❑

Sense resistor programmed 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 , <0.4mA Sleep Mode

❑

PWRGD Flag

❑

Small SOIC-8 Package

Applications

❑

-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

General Description

The Supertex HV301 and HV311 Hotswap 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.

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

(continued on Page 21)

VDD

UV

OV

VEE

SENSE

GATE

-48V

R4

12.5m

Ω

R1

487k

Ω

R2

6.81k

Ω

R3

9.76k

Ω

Q1

IRF530

Cload

+5V

HV301/

HV311

8

3

2

5

4

COM

DC/DC

PWM

CONVERTER

1

GND

PWRGD / PWRGD

ENABLE / ENABLE

6

RAMP

7

C1

10nF

C2

-48V

Notes: 1. Undervoltage Shutdown (UV) set to 35V.

2. Overvoltage Shutdown (OV) set to 65V.

3. Current Limit set to -1A.

4. CB set to 8A.

Typical Application Circuit

0.75nF

Hotswap, Controllers with Circuit Breaker

(Negative Supply Rail)

HV301

HV311

Demo Kit

Available