MC34704AEP Freescale Semiconductor, MC34704AEP Datasheet - Page 33

• Manufacturer Part Number: MC34704AEP
• Description: IC POWER MANAGEMENT 56-QFN
• Manufacturer: Freescale Semiconductor

Specifications of MC34704AEP

• Applications: Processor
• Current - Supply: 86mA
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: -20°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 56-QFN
• Output Voltage: 5 V
• Input Voltage: 2.7 V to 5.5 V
• Switching Frequency: 750 KHz to 2 MHz
• Mounting Style: SMD/SMT
• Number Of Outputs: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

On/Off Control for each group of regulators as defined
previously and for the whole IC
(ONOFFA, C, D, or E bits). Please note that GrpB does not
have a dedicated enable register which is enabled by default.
IC through the I
Soft Start Time
all of the regulators except REG1. The SSTIME[1:0] bits
reads the soft start value set by the SS pin and is used to
initially set the soft start value for all of the regulators except
REG1. Then, the SSSET bits for REG5 through REG8 can be
used to change the soft start value for these regulators from
the value set by the SSTIME.
Analog Integrated Circuit Device Data
Freescale Semiconductor
34704 assigns 1 bit per group to turn each group on/off
Also, 34704 assigns 1 bit (ALLOFF) for disabling the whole
There are two set of bits for setting the soft start value for
Percentage Change
0.00% (Default)
+10.00%
+12.50%
+15.00%
+17.50%
-20.00%
-17.50%
-15.00%
-12.50%
-10.00%
+2.50%
+5.00%
+7.50%
-7.50%
-5.00%
-2.50%
GrpA, C, D, or E ONOFF
2
C. (ALLOFF bit)
False (Default)
OFF (Default)
ALL OFF
True
ON
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
bit
0
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
bit
0
1
LSB
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
register bits:
SS pin. Bits SSTIME[1:0] can only be read by the user.
the soft start times for these regulators (SSSETx[1:0]) where
x corresponds to each regulator from REG5 through REG8.
REG8 Regulation Mode
mode (REG8MODE). The processor assigns this bit 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.
I
mode limitation.
MAX
1. SSTIME is set by a value read through the SS pin.
2. SSTIME is copied into the bits SSSET5, SSSET6,
3. The soft start time of REG2, REG3, and REG4 are only
4. The soft start time of REG5, REG6, REG7, and REG8
Here is how the SSTIME bits interacts with the SSSETx
34704 assigns 2 bits to store the value programmed by the
34704 assigns 2 bits for REG5 through REG8 to program
The 34704 assigns 1 bit to indicate REG8’s regulation
The maximum LED current can be set using the external
34704 assigns 4 bits for this function (ILED[3:0])
The ILED setting is not a guaranteed characteristic from
* (1/16) to I
2
SSSET7, and SSSET8.
affected by the value of SSTIME bits.
are affected by the value of bits SSSET5, SSSET6,
SSSET7, and SSSET8 respectively.
C interface
Soft Start
MAX
Soft Start
0.5ms
0.5ms
REG8 Regulation
32ms
32ms
Current (Default)
2ms
8ms
2ms
8ms
* (9/16), due to an error amp common
Voltage
LOGIC COMMANDS AND REGISTERS
FUNCTIONAL DEVICE OPERATION
MSB
MSB
0
0
1
1
0
0
1
1
bit
0
1
LSB
LSB
0
1
0
1
0
1
0
1
2
C
34704
33