13

 2005 Semtech Corp.

www.semtech.com

POWER MANAGEMENT

SC900

Applications Information (Cont.)

Output Voltage Code Bits:

A 5-bit linear DAC controls the output voltage of each LDO. The DAC and error-amp gain are scaled so that the LSB

size at the output is 50mV. Output voltage can be set by writing the proper code to the desired LDO register. See

Table A for the bitcodes and their corresponding voltages.

Table A - LDO Output Voltage Control Settings

4

t

i

B3

t

i

B2

t

i

B1

t

i

B0

t

i

Be

g

a

t

l

o

V

t

u

p

t

u

O

O

D

L

0

0000

V

5

4

.

1

0

000

1

V

0

5

.

1

00

0

1

0

V

5

5

.

1

00

0

1

1

V

0

6

.

1

00

1

0

0

V

5

6

.

1

-

----

-

-

----

-

1

111

0

V

5

9

.

2

1

1111

V

0

0

.

3

program flexibility, in that once the slave address has been sent to the SC900 enabling it to be a slave transmitter/

receiver, any register can be written or read from independent of each other. While there is no auto increment/

register independent of which register you begin accessing. The start and stop commands frame the data-packet

and the repeat start condition is allowed if necessary.

Seven-bit addressing is required for communicating with the SC900; ten-bit addressing is not allowed. Any general

call address will be ignored by the SC900. Note that the SC900 is not CBUS compatible. Finally, the SC900 can

operate in standard mode (100kbit/s) or fast mode (400kbit/s).