MAX16809ATU+T Maxim Integrated Products, MAX16809ATU+T Datasheet - Page 14

• Manufacturer Part Number: MAX16809ATU+T
• Description: IC LED DRVR WT/RGB BCKLT 38-TQFN
• Manufacturer: Maxim Integrated Products
• Type: Backlight, White LED, RGB (Serial Interface)r

Specifications of MAX16809ATU+T

• Constant Current: Yes
• Topology: *
• Number Of Outputs: 16
• Internal Driver: Yes
• Type - Primary: Backlight
• Type - Secondary: RGB, White LED
• Frequency: 20kHz ~ 1MHz
• Voltage - Supply: 8 V ~ 26.5 V
• Voltage - Output: 36V
• Mounting Type: Surface Mount
• Package / Case: 38-TQFN Exposed Pad
• Operating Temperature: -40°C ~ 125°C
• Current - Output / Channel: 55mA
• Internal Switch(s): No
• Low Level Output Current: 6 mA
• High Level Output Current: 1.8 mA
• Operating Supply Voltage: 3 V to 5.5 V
• Maximum Supply Current: 5 mA
• Maximum Power Dissipation: 2857 mW
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Efficiency: -
• Lead Free Status / Rohs Status: Details

The oscillator frequency is then:
REF is a 5V reference output that can source 20mA.
Bypass REF to AGND with a 0.1μF capacitor.
The MAX16809 includes a fast current-limit comparator
to terminate the ON cycle during an overload or a fault
condition. The current-sense resistor, R
between the source of the external MOSFET and
AGND, sets the current limit. The CS input has a volt-
age trip level (V
to calculate R
Integrated 16-Channel LED Driver with
Switch-Mode Boost and SEPIC Controller
Figure 2. Buck-Boost (SEPIC) Operation
14
3V TO 5.5V
V
IN
CLOCK INPUT
______________________________________________________________________________________
EXTERNAL
DIM INPUT
EXTERNAL
R
C
SET
BYP
C
IN
CS
V
V+
PGND
DIN
LE
CLK
DOUT
OE
SET
CS
OUT CS AGND
:
CC
L1
C
REF
) of 0.3V. Use the following equation
f
OSC
REF
MAX16809
=
Q1
R
R
(
T
CS
COMP
t
C
C
1
1
+
L2
C
RTCT
t
C1
Reference Output
D
C
)
C2
C
OUT10
OUT11
OUT12
OUT13
OUT14
OUT15
D
T
OUT0
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
OUT7
OUT8
OUT9
R
C
C1
FB
OUT
Current Limit
CS
, connected
R1
R2
V
OUT
I
When the voltage produced by this current (through the
current-sense resistor) exceeds the current-limit com-
parator threshold, the MOSFET driver (OUT) turns the
switch off within 60ns. In most cases, a small RC filter is
required to filter out the leading-edge spike on the
sense waveform. Set the time constant of the RC filter at
50ns.
Figure 2 shows a buck-boost application circuit using
the MAX16809 in a stand-alone mode of operation.
SEPIC topology is necessary when the total forward
voltage of the LEDs in a string is such that V
below or above V
P-P
is the peak current that flows through the MOSFET.
Buck-Boost (SEPIC) Operation
IN
.
R
CS
=
I
V
P P
CS
−
OUT
can be