MAX16809 Datasheet, PDF (12/23 Pages) Maxim Integrated Products – Integrated 16-Channel LED Drivers with Switch-Mode Boost and SEPIC Controller

Integrated 16-Channel LED Drivers with
Switch-Mode Boost and SEPIC Controller
cathode of a string of LEDs connected in series. The
constant-current capability is up to 55mA per output,
set for all 16 outputs by an external resistor, R_SET. The
devices can operate in a stand-alone mode (see the
Typical Operating Circuits).
The MAX16810 includes circuitry that automatically
detects open-circuit LEDs. Fault status is loaded into the
serial-interface shift register when LE goes high and is
automatically shifted out on DOUT when the next data
transmission is shifted in. The MAX16810 also features a
watchdog that monitors activity on the CLK, DIN, and LE
inputs (see the Watchdog (MAX16810) section). The
number of channels can be expanded by using the
MAX6970 and MAX6971 family in conjunction with the
MAX16809 and MAX16810.
AGND
CS
FB
COMP
CLK
DIN
LE
OE
MAX16809
REFERENCE
2.5V
PREREG
5V
DELAY
REG_OK
UVLO
THERMAL
SHUTDOWN
EN_REF ^VDD
BG 5V REG
SNS
VOLTAGE
DIVIDER
VOLTAGE-
DIVIDER
26.5V
300mV _ILIM
VCC
SQ
R
CPWM
2R
VEA
CLK
R
OSC Q
SERIAL-TO-PARALLEL SHIFT REGISTER
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
OUTPUT LATCHES
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
THERMAL
SHUTDOWN
CONSTANT-CURRENT SINK
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
POWER-ON
RESET
V+
CURRENT
REFERENCE
PGND
VCC
REF
OUT
RTCT
DOUT
V+
SET
Figure 1a. Internal Block Diagram (MAX16809)
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