MAX16807_09 Datasheet, PDF (17/19 Pages) Maxim Integrated Products – Integrated 8-Channel LED Driver with Switch-Mode Boost and SEPIC Controller

Integrated 8-Channel LED Driver with
Switch-Mode Boost and SEPIC Controller
Computing Power Dissipation
Use the following equation to estimate the upper limit
power dissipation (PD) for the MAX16807:
⎡
i=7
⎤
PD = DUTY x _⎢(V + x I+) + ∑ V_OUTi x I_OUTi⎥ + (V_CC x I_CC)
⎣⎢
i=0
⎦⎥
where:
V+ = supply voltage
I+ = operating supply current
DUTY = PWM duty cycle applied to OE
V_OUTi = MAX16807 port output voltage when driving
load LED(s)
I_OUTi = LED drive current programmed by R_SET
PD = power dissipation.
PCB Layout Guidelines
Careful PCB layout is critical to achieve low switching
losses and clean, stable operation. Use a multilayer
board whenever possible for better noise immunity.
Protect sensitive analog grounds by using a star
ground configuration. Minimize ground noise by con-
necting AGND, PGND, the input bypass-capacitor
ground lead, and the output-filter ground lead to a sin-
gle point (star ground configuration). Also, minimize
trace lengths to reduce stray capacitance, trace resis-
tance, and radiated noise. The trace between the out-
put voltage-divider and the FB pin must be kept short,
as well as the trace between AGND and PGND.
Pin Configuration
TOP VIEW
+
N.C. 1
AGND 2
OUT 3
VCC 4
REF 5
MAX16807
OUT4 6
OUT5 7
OUT6 8
OUT7 9
OE 10
DOUT 11
SET 12
N.C. 13
V+ 14
28 N.C.
27 RTCT
26 CS
25 FB
24 COMP
23 OUT3
22 OUT2
21 OUT1
20 OUT0
19 LE
18 CLK
17 DIN
16 PGND
15 PGND
TSSOP-EP
PROCESS: BiCMOS
Chip Information
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