MAX16807AUI+T Maxim Integrated Products, MAX16807AUI+T Datasheet - Page 14

• Manufacturer Part Number: MAX16807AUI+T
• Description: IC LED DRVR WT/RGB BCKLT 28TSSOP
• Manufacturer: Maxim Integrated Products
• Type: Backlight, White LED, RGB (Serial Interface)r

Specifications of MAX16807AUI+T

• Constant Current: Yes
• Topology: Open Drain, PWM, Step-Down (Buck), SEPIC, Step-Up (Boost)
• Number Of Outputs: 8
• 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: 28-TSSOP Exposed Pad, 28-eTSSOP, 28-HTSSOP
• Operating Temperature: -40°C ~ 125°C
• Current - Output / Channel: 55mA
• Internal Switch(s): No
• Operating Supply Voltage: 3 V to 5.5 V
• Maximum Supply Current: 5 mA
• Maximum Power Dissipation: 2162 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 MAX16807 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 8-Channel LED Driver with
Switch-Mode Boost and SEPIC Controller
Figure 2. Buck-Boost (SEPIC) Configuration
14
______________________________________________________________________________________
3V TO 5.5V
CS
CS
:
CLOCK INPUT
f
) of 0.3V. Use the following equation
OSC
EXTERNAL
DIM INPUT
R
EXTERNAL
V
SET
IN
C
BYP
C
IN
=
(
t
C
V
V+
PGND
DIN
LE
CLK
DOUT
OE
SET
OUT CS AGND
CC
+
1
L1
C
REF
Reference Output
t
D
REF
)
Current Limit
MAX16807
CS
Q
R
R
CS
T
COMP
, connected
C1
C
L2
T
C
RTCT
C1
C
C2
D
OUT0
OUT1
OUT2
OUT3
OUT4
OUT5
OUT6
OUT7
R
C
C1
FB
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 MAX16807 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
R1
R2
P-P
V
OUT
is the peak current that flows through the MOSFET.
Buck-Boost (SEPIC) Operation
IN
R
.
CS
=
I
V
P P
CS
−
LEDs
OUT
can be