MC34704 FREESCALE [Freescale Semiconductor, Inc], MC34704 Datasheet - Page 32

• Manufacturer Part Number: MC34704
• Description: Multiple Channel DC-DC Power Management IC
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

REG8 Regulation Mode
regulation mode ( REG8MODE Register ). The processor
assigns this register to either regulation mode before
enabling the REG8 output.
When REG8 is current regulated, LED backlight current
can be reduced from the maximum in 16 steps through
the I
resistor at the bottom of the LED string, then through I
programming, this current value can be reduced in 16 steps.
register )
I
mode limitation.
MAX
The 34704 assigns a 1-bit register to indicate REG8’s
The maximum LED current can be set using the external
34704 assigns a 4-bit register for this function ( ILED
The ILED setting is not a guaranteed characteristic from
2
* (1/16) to I
I
I
I
I
I
I
I
C interface
LED Current
I
I
I
I
I
I
I
I
I
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
MAX
32
34704
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
* (10/16)
* (11/16)
* (12/16)
* (13/16)
* (14/16)
* (15/16)
(Default)
* (1/16)
* (2/16)
* (3/16)
* (4/16)
* (5/16)
* (6/16)
* (7/16)
* (8/16)
* (9/16)
Soft Start
MAX
0.5ms
REG8 Regulation
32ms
Current (Default)
2ms
8ms
* (9/16), due to an error amp common
Voltage
MSB
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
MSB
0
0
1
1
bit
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
LSB
0
1
0
1
LSB
2
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
C
USER ACCESSIBLE FLAG REGISTERS
Cold Start Flag
flag the processor that the power up was a result of battery
insertion and not through ONOFF pin. This flag should be
cleared after power up by the processor.
Shutdown Flag
to flag the processor if a shutdown signal is received through
the ONOFF pin and a programmable time period with a
default of 1sec has elapsed.
Dynamic Voltage Scaling Status Flag
register ( DVSSTATx register ) to flag to the processor that the
desired output voltage level set with the ( DVSSETx register )
has been reached.
USER ACCESSIBLE FAULT REGISTERS
Over-current Fault Register
( ILIMFx Register ) to indicate a fault due to over-current limit,
where x corresponds to each regulator from REG1 to REG8,
except REG7
Short-circuit Fault Register
( SCFx Register ) to indicate a fault due to short-circuit current
limit, where x corresponds to each regulator from REG1 to
REG8, except REG7
The 34704 assigns a 1-bit register ( COLDF Register ) to
The 34704 assigns a 1-bit register ( SHUTDOWN Register )
In addition and for each regulator, 34704 assigns a 1-bit
The 34704 assigns a 1-bit register for each regulator
The 34704 assigns a 1-bit register for each regulator
/ONOFF (Default)
Battery Insertion
Normal (Default)
Cold Start Flag
/ONOFF Status
DVS Not Done
DVS STATUS
DVS Done
Shutdown
ILIMF
False
True
Analog Integrated Circuit Device Data
Freescale Semiconductor
bit
bit
bit
0
1
0
1
0
1
bit
0
1