APEX MICROTECHNOLOGY CORPORATION • 5980 NORTH SHANNON ROAD • TUCSON, ARIZONA 85741 • USA • APPLICATIONS HOTLINE: 1 (800) 546-2739

This data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. All specificiations are subject to change without notice.

EBO1U REV. B JANUARY 2001 © 2001 Apex Microtechnology Corporation

EB01

OPERATING

CONSIDERATIONS

POWER SUPPLY REQUIREMENTS

SUPPLY

VOLTAGE

MAX CURRENT

HV1

50V to 500V

20A, continuous, 28A peak

HV2

50V to 500V

20A, continuous, 28A peak

HV3

50V to 500V

20A, continuous, 28A peak

10V to 20V

10mA

10V to 20V

10mA

10V to 20V

10mA

4.5 to 20V

10mA

HV1, HV2, and HV3 may be used independently, or may

compatible with the input logic. If a high voltage logic such as

requires a 5V±10% supply

SPECIAL CONSIDERATIONS

GENERAL

The EB01 is designed to give the user maximum flexibility

in a digital or DSP based motion control system. Thermal,

overvoltage, overcurrent, and crossfire protection circuits are

part of the user’s design.

Users should read Application Note 1, "General Operating

Considerations;” and Application Note 30, “PWM Basics”

for much useful information in applying this part. These

Application Notes are in the “Power Integrated Circuits Data

Book” and on line at www.apexmicrotech.com.

GROUNDING AND BYPASSING

As in any high power PWM system, grounding and

bypassing are one of the keys to success. The EB01 is

capable of generating 20 kW pulses with 100 n-second rise

and fall times. If improperly grounded or bypassed this can

cause horrible conducted and radiated EMI.

In order to reduce conducted EMI, the EB01 provides a

separate power ground, named HVRTN, for each high voltage

supply. These grounds are electrically isolated from the logic

current ground loops. However, more than 5V offset between

the grounds will destroy the EB01. Apex recommends

back to back high current diodes between logic and power

grounds; this will maintain isolation but keep offset at a

safe level. All grounds should tie together at one common

point in the system.

In order to reduce radiated EMI, Apex recommends a

400 µF or larger capacitor between HV and HVRTN. This

capacitor should be a a switching power grade electrolytic

capacitor with ESR rated at 20 kHz. This capacitor should be

placed physically as close to the EB01 as possible.

However, such a capacitor will typically have a few

hundred milli-ohms or so ESR. Therefore, each section

must also be bypassed with a low ESR 1µF or larger

ceramic capacitor.

In order to minimize radiated noise it is necessary to

minimize the area of the loop containing high frequency

current. (The size of the antenna.) Therefore the 1µF ceramic

capacitors should bypass each HV to its return right at

the pins the EB01.

SHOOT THROUGH PROTECTION

IGBTs have a relatively short turn on delay, and a long

turn off delay. Unlike most semiconductor devices the turn off

delay cannot be improved very much by drive circuit design.

Therefore, if the turn on input to an IGBT in a half bridge

circuit is applied simultaneously with the turn off input to

the other IGBT in that half bridge, there will be a time when

both IGBTs are simultaneously on. This will short the power

rails through the IGBTs, causing excessive power dissipation

and very high EMI.

To avoid the shoot through condition the turn on of one

IGBT must be delayed long enough for the other in the same

half bridge to have completely turned off.

A delay of at least 1.5 µ-seconds is required for the EB01.

This delay must be provided after turning off Lin before Hin

of the same half bridge may be turned on; likewise it must

be provided after turning off Hin before Lin of the same half

bridge may be turned on.

PROTECTION CIRCUITS

The EB01 does not include protection circuits.

However, there is a shut down input which will turn off all

IGBTs when at logic “1”. This input may be used with user

designed temperature sensing and current sensing circuits

to shut down the IGBTs in the event of a detected unsafe

condition. This is recommended since the IGBTs may be

turned off this way even if the normal input logic or DSP

programming is faulty.

START-UP REQUIREMENTS

In order for an IGBT to be turned on, the corresponding

logic input signal must make its positive transition after SD

has been low for at least 1 µ-second.

The lower rail IGBT in the half bridge must be turned on

for at least 2 µ-seconds to charge the bootstrap capacitor

before the top rail IGBT can be turned on. This must be done

no more than 330 µ-seconds prior to turning on the top rail

IGBT. However, if the load pulls the output to ground, the

positive rail IGBT can be turned on without first briefly turning

on the negative rail IGBT.

An internal floating supply is used to enhance the operation

of the bootstrap bias circuit. This allows the top rail IGBTs to

be held on indefinitely once turned on.

HEATSINK

The EB01 should be provided with sufficient heatsink to

dissipate 179 watts while holding a case temperature of

25°C when operating at 500V, 20A, 30kHz and 3 sections

simultaneously providing maximum current.

up to 54 watts per half bridge and switching losses of about 4

watts per half bridge. The conduction losses are proportional

and to switching frequency.