POWER INT201TF1, INT201PF1 Datasheet

February 1996

Product Highlights

Floating Control Inputs

• Connects directly to INT200 or INT202 HSD outputs

• No external level translators or transformers required

Gate Drive Output for an External MOSFET

• Provides 300 mA sink/150 mA source current

• Can drive MOSFET gate at up to 15 V

• Floating source for driving high-side N-channel MOSFET

• External MOSFET allows flexibility in design for various motor sizes

Built-in Protection Circuits

• Logic inputs include noise rejection circuitry

• Undervoltage lockout

Description

The INT201 high-side driver IC provides gate drive for an external high-side MOSFET switch. When used in conjunction with the INT200 or INT202 low-side drivers, the INT201 provides a simple, cost-effective interface between low-voltage control logic and high-voltage loads.

Built-in noise rejection circuitry shared between the INT201 and the INT200 or INT202 provides reliable operation in the harshest industrial environments. The INT201 is powered from a ground-referenced low-voltage supply. A floating supply is derived from this rail by using a simple bootstrap technique to provide adequate gate drive for the external N-channel MOSFET.

Applications include motor drives, electronic ballasts, and uninterruptible power supplies. The INT201 can also be used to implement full-bridge and multi-phase configurations.

The INT201 is available in 8-pin plastic DIP and SOIC packages.

INT201

High-side Driver IC

Floating Inputs Floating High-side Drive

®

ORDERING INFORMATION

PART PACKAGE TEMP

NUMBER OUTLINE RANGE

INT201PFI P08A -40 to 85°C INT201TFI T08A -40 to 85°C

Figure 1. Typical Application.

Figure 2. Pin Configuration.

PI–285D–091191

HSD2

SOURCE

HS OUT

N/C

HSD1

DDH

N/C

HS IN

LS IN



INT201



INT200

PI-1764-020196

3-PHASE

BRUSHLESS

DC MOTOR

INT201

F 2/96

Pin Functional Description

Pin 1:

No connection.

Pin 2:

No connection.

Pin 3:

Level shift input HSD 1 works in conjunction with HSD 2 to provide interface from the low side control logic and to give noise immunity.

Pin 4:

Level shift input HSD 2 works in conjunction with HSD 1 to provide interface from the low side control logic and to give noise immunity.

Pin 5: SOURCE connection. Analog reference

point for the circuit, normally connected to the source of the high side MOSFET.

Pin 6: HS OUT is the output of the MOSFET

driver for the high side.

Pin 7:

No connection.

Pin 8: V

DDH

supplies power to the control logic

and output driver.

INT201 Functional Description

5 V Regulator

The 5 V linear regulator circuit provides the supply voltage for the noise rejection circuitry and control logic. This allows the logic section and the driver circuitry to be directly compatible with 5 V CMOS logic without the need of an external 5 V supply.

Undervoltage Lockout

The undervoltage lockout circuit disables the HS OUT pin whenever the V

DDH

power supply falls below 9.0 V, and maintains this condition until the V

DDH

power supply rises above 9.35 V. This guarantees that the high side MOSFET will be off during power-up or fault conditions.

Noise Immunization Circuit

This circuit provides noise immunity by combining a sampling circuit with a flip-flop to turn on and off the driver only when required to and not when there is noise on the HSD inputs.

Driver

The CMOS driver circuit provides drive power to the gate of the MOSFET used on the high side of the half bridge circuit. The driver consists of a CMOS buffer capable of driving external transistors at up to 15 V. The SOURCE pin is connected to the source of the external MOSFET to establish a reference for the gate voltage.

Figure 3. Functional Block Diagram of the INT201.

HSD1

HSD2

DDH

SOURCE

PI-514B-021792

HS OUT

LINEAR

REGULATOR

UV

LOCKOUT

DISCRIMINATOR

DELAY

2/96

INT201

Figure 4. Using the INT200 and INT201 in a 3-phase Configuration.

General Circuit Operation

One phase of a three-phase brushless DC motor drive circuit is shown in Figure 4 to illustrate an application of the INT200/201. The LS IN signal directly controls MOSFET Q1. The

HS IN

signal causes the INT200 to command the INT201 to turn MOSFET Q2 on or off as required. The INT200 will ignore input signals that would command both Q1 and Q2 to conduct simultaneously, protecting against shorting the HV+ bus to HV-.

Local bypassing for the low-side driver is provided by C1. Bootstrap bias for the high-side driver is provided by D1 and C2. Slew rate and effects of parasitic oscillations in the load waveforms are controlled by resistors R1 and R2.

The inputs are designed to be compatible with 5 V CMOS logic levels and should not be connected to VDD. Normal CMOS power supply sequencing should be observed. The order of signal application should be VDD, logic signals, and then HV+.

The INT201 is latched on and off by the edges of the appropriate low-side logic signal (

HS IN

for the INT200 and

HS IN

for the INT202). The high-side driver will latch off and stay off if the bootstrap capacitor discharges below the

undervoltage lockout threshold. Undervoltage lockout-induced turn off can occur during conditions such as power ramp up, motor start, or low speed operation.

Figure 5. High-side On Time versus Bootstrap Capacitor.

PI-1467-042695

HV+

LS IN

HV-

INT201

INT200

PHASE 1

PHASE 2

PHASE 3

3-PHASE

BRUSHLESS

DC MOTOR

HS IN

1234

8765

1234

8765

1000

0.1

0.01

0.01 0.1 1 10 100

High Side ON Time (ms)

Bootstrap Capacitance (µF)

BOOTSTRAP

vs. ON TIME

100

PI-566B-030692

QG = 20 nC

QG = 100 nC

INT201

F 2/96

Figure 6. Using the INT202 and INT201 to Drive a Switched Reluctance Motor.

General Circuit Operation (cont.)

The bootstrap capacitor must be large enough to provide bias current over the entire on time interval of the high-side driver without significant voltage sag or decay. The MOSFET gate charge must also be supplied at the desired switching frequency. Figure 5 shows the maximum high-side on time versus gate charge of

the external MOSFET. Applications with extremely long high-side on times require special techniques discussed in AN-10.

A three-phase switched reluctance motor example using the INT202/201 is given in Figure 6. The LS IN signal directly

controls MOSFET Q1. Unlike the INT200, the INT202 allows both the low and high-side drivers to be on at the same time, as this is required in applications where the load is placed between the low and high-side output MOSFETs.

PI-1468-042695

HV+

CONTROL

HV-

1234

8765

1234

8765

INT201

INT202

PHASE 1

PHASE 2

PHASE 3

3-PHASE

SRM

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