MC34844AEP Freescale Semiconductor, MC34844AEP Datasheet - Page 43

• Manufacturer Part Number: MC34844AEP
• Description: IC LED DVR BACKLIGHT 10CH 32QFN
• Manufacturer: Freescale Semiconductor

Specifications of MC34844AEP

• Constant Current: Yes
• Internal Driver: Yes
• Type - Primary: Backlight
• Mounting Type: Surface Mount
• Topology: PWM, Step-Up (Boost)
• Number Of Outputs: 10
• Frequency: Adjustable/Selectable
• Voltage - Supply: 7 V ~ 28 V
• Voltage - Output: 60V
• Package / Case: 32-VFQFN Exposed Pad
• Operating Temperature: -40°C ~ 105°C
• Operating Supply Voltage: 7 V to 28 V
• Maximum Supply Current: 10 mA
• Maximum Power Dissipation: 3.9 W
• Maximum Operating Temperature: + 105 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

A0/SEN
voltage Protection (OVP) Control.
CURRENT SET (ISET)
current can be set by using a resistor from this pin to GND.
POSITIVE CURRENT SCALING (PIN)
current control. Applying 0 V to this pin, scales the current to
near 0%, and in the same way, applying V
the scale factor is 100%. By applying a voltage higher than
2.2 V, the scaling factor is disabled, and the internal pull-ups
are activated.
applying 0 V to the PIN pin and V
current to near 0%, and in the same way, applying V
the PIN pin and 0 V to NIN pin, scales the current to 100%.
By applying a voltage higher than 2.2 V, the scaling factor is
disabled and the internal pull-ups are activated in both pins.
NEGATIVE CURRENT SCALING (NIN)
current control. Setting 0 V to this pin scales the current to
100%, in the same way, setting V
factor is near 0%. By applying a voltage higher than 2.2 V, the
scaling factor is disabled and the internal pull-ups are
activated.
applying 0 V to the PIN pin and V
current to near 0%, and in the same way, applying V
PIN pin and 0 V to NIN pin, scales the current to 100%. By
Analog Integrated Circuit Device Data
Freescale Semiconductor
Address select, device select pin, or Hardware Over-
Each LED string can drive up to 50 mA. The maximum
Positive current scaling factor for the external analog
If PIN pin and NIN pin are used at the same time then by
Negative current scaling factor for the external analog
If PIN pin and NIN pin are used at the same time then by
SET
SET
SET
(2.048 V Typ.) the scale
to NIN pin, scales the
to NIN pin, scales the
SET
(2.048 V Typ.),
SET
SET
to the
to
applying a voltage higher than 2.2 V, the scaling factor is
disabled and the internal pull-ups are activated in both pins.
GROUND (GND)
Boost FET.
dissipation.
I0-I9
up to 50 mA.
FAULT DETECTION PIN (FAIL)
impedance.
BOOST SLOPE COMPENSATION SETTING
RESISTOR (SLOPE)
Input and Output voltage difference as well as the inductor
value. Please use the formula shown in the
Calculation
POWER GROUND TERMINALS (PGNDA, PGNDB)
OUTPUT VOLTAGE SENSE TERMINAL (VOUT)
supplies the input voltage for the internal regulator 2 (VDC2).
SWITCHING NODE TERMINALS (SWA, SWB)
Ground Reference for all internal circuits other than the
The Exposed Pad (EP) should be used for thermal heat
Current LED driver, each line has the capability of driving
When a fault situation is detected, this pin goes into high
The resistor to be used for the SLOPE depends on the
Ground terminal for the internal Boost FET.
Input terminal to monitor the output voltage. It also
Switching node of boost converter.
section to calculate the value accordingly.
FUNCTIONAL PIN DESCRIPTION
FUNCTIONAL DESCRIPTION
Components
34844A
43