33702 Datasheet, PDF (21/24 Pages) Motorola, Inc – 3.0 A Switch-Mode Power Supply with Linear Regulator

Freescale Semiconductor, Inc.
Communication Stop
Only the master can terminate the data transfer by issuing a
STOP condition. The slave waits for this condition to resume its
initial state waiting for the next START condition (see
Figure 19).
Data Transfer Example
The master device controlling the I²C bus will always start
addressing a 33702 slave IC in writing mode (R/W = 0) in order
to be able to write a Command Byte just after the address
acknowledge. I²C bus protocol defines this circumstance as a
master-transmitter and slave-receiver configuration.
Eventually this Command Byte can again define a Write
operation (e.g., Voltage Margining, see Figure 19), and the
master will keep the data transfer direction.
Figure 19 illustrates a communication beginning with the
slave address, the first command for voltage margining, and a
third byte containing the address field 001 and the value field
00101 corresponding with the LDO fifth setting (LDO output
voltage = +5% above its nominal value). If a simultaneous
setting for switcher is needed, a fourth byte should be included
before the STOP condition (P); for instance, 001 10010 to set
switcher in its second setting (switcher output voltage = +2%
above its nominal value).
S A6 A5 A4 A3 A2 A1 A0 0 Ack
START
Slave Address
Write
0 0 1 0 0 0 0 0 Ack
First Command for Voltage Margining
0 0 1 0 0 1 0 1 Ack P
Address Field Value Field = LDO
5^th Setting
STOP
Figure 19. Complete Data Transfer Example
MOTOROLA ANALOG INTEGRATED CI_FRC_oU_rIT_MD_oE_rV_eICE_InD_fA_oT_rA_{mation On This Product,}
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33702
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