PA13 • PA13A

6

PA13U

P r o d u c t I n n o v a t i o n F r o m

®

1. Capacitive and dynamic* inductive loads up to the following maximum are safe with the current limits set as

specified.

CAPACITIVE LOAD

INDUCTIVE LOAD

±V

S

I

I

I

I

50V

200µF

125µF

5mH

2.0mH

40V

500µF

350µF

15mH

3.0mH

35V

2.0mF

850µF

50mH

5.0mH

30V

7.0mF

2.5mF

150mH

10mH

25V

25mF

10mF

500mH

20mH

20V

60mF

20mF

1,000mH

30mH

15V

150mF

60mF

2,500mH

50mH

*If the inductive load is driven near steady state conditions, allowing the output voltage to drop more than 12.5V be-

low the supply rail with ILIM = 10A or 27V below the supply rail with ILIM = 5A while the amplifier is current limiting,

the inductor must be capacitively coupled or the current limit must be lowered to meet SOA criteria.

2. The amplifier can handle any EMF generating or reactive load and short circuits to the supply rail or common if

the current limits are set as follows at TC = 25°C:

SHORT TO ±V

S

SHORT TO

±V

S

C, L, OR EMF LOAD

COMMON

45V

.43A

3.0A

40V

.65A

3.4A

35V

1.0A

3.9A

30V

1.7A

4.5A

25V

2.7A

5.4A

20V

3.4A

6.7A

15V

4.5A

9.0A

These simplified limits may be exceeded with further analysis using the operating conditions for a specific applica-

tion.

CURRENT LIMITING

Refer to Application Note 9, "Current Limiting", for details of both fixed and foldover current limit operation. Visit the

Apex Precision Power web site at www.cirrus.com for a copy of Power_design.exe which plots current limits vs.

steady state SOA. Beware that current limit should be thought of as a ±20% function initially and varies about 2:1

over the range of –55°C to 125°C.

For fixed current limit, leave pin 4 open and use equations 1 and 2.

R

0.65

I

CL

(1)

I

0.65

R

CL

(2)

Where:

I

R