RT4832A

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is a registered trademark of Richtek Technology Corporation.

www.richtek.com

DS4832A-00

January

2017

16

Application Information

I

S 0 0 1 0 0 0 1 0

R/W

A

P

Slave ID

Data Address

S 0 0 1 0 0 0 1 0

R/W

A

Slave ID

Data Address

A

ACK from Slave

ACK from Slave

ACK from Slave

Write Data1

A

ACK from Slave

A

Read Data1

ACK from Master

A P

NACK from Master

Read Data2

A

A

0 0 1 0 0 0 1 1

ACK from Slave

ACK from Slave

R/W

Slave ID

P

P

Write Data2

A

ACK from Slave

DSV

The RT4832A provides programmable LCMOUT, POS,

CPOUT value. Table 1 contains the detail for DSV

operation setting. The LCMOUT should be selected to

provide enough headroom for good ripple and load

transient performance. The headroom voltage between

LCMOUT and the maximum value of VPOS and

|VCPOUT| should be higher than 150mV for good

performance but the headroom voltage between

LCMOUT and |VCPOUT| should not be higher than

200mV to avoid the larger ripple at VCPOUT.

The OCP level of POS is 250mA and CPOUT is 150mA

typically.

Table 1. DSV Operation Setting

Channel

Range

Step

Register

Default Value

Suggest Setting

LCMOUT

4V to 6.15V

50mV/LSB

0x0D[5:0]

6V

5.7V

VPOS

4V to 6V

50mV/LSB

0x0E[5:0]

5.5V

5.5V

CPOUT

4V to 6V

50mV/LSB

0x0F[5:0]

5.4V

5.5V

The DSV con be controlled either by pins or register bits. Table 2 is the DSV operation control table.

Table 2. DSV Operation Control Table

EN pin

ENP pin

ENM pin

Dsv_ext_en

0x09[5]

DSV_vpos_en

0x0C[6]

DSV_vneg_en

0x0C[3]

Status

0

X

X

X

X

X

Shutdown

1

X

X

0

0

0

Standby

1

0

0

1

X

X

Standby

1

X

X

0

1

0

VPOS enable

1

X

X

0

0

1

VNEG enable

1

X

X

0

1

1

VPOS & VNEG enable

1

1

0

1

X

X

VPOS enable

1

0

1

1

X

X

VNEG enable

1

1

1

1

X

X

VPOS & VNEG enable