Datasheet

18 LED Lighting Solutions Design Guide www.microchip.com/lighting
LED Lighting Solutions
Using TC6501 Open Drain Output for
Current Set-Point Control
There are different ways that the TC6501 and TC6502
temperature sensors can be used in an application. The
open-drain output of the TC6501 is useful for controlling
signals in analog circuits. For example, the TC6501 could
be used to limit a current reference set-point for a switch-
mode power supply. It could also be connected to signals in
op amp circuits to alter the behavior of the system when a
temperature limit is exceeded (see figure below).
Using the TC6501 to Provide MCU Interrupt
If a microcontroller is present and managing the application,
a TC6502 with CMOS active-high output signal can be used
to provide an interrupt. The microcontroller in turn will be
able to apply PWM dimming techniques to reduce the power
output to the module (as shown in figure below).
LED
Dimming
Signal
+5V
PIC12F683
V CC
GP0
GND
V
CC
PWM
TC6502
GND GND HIST
T OVER
+12V
Fan
+5V
GND GND
HIST
V
CC
T OVER
TC6502
Using TC6501 Open Drain Output for Current Set-Point Control
Using the TC6501 to Provide MCU Interrupt
Fan Controller Application Using TC6502
If a cooling device (fan) is available, a TC6502 device (with
the HYST pin connected to VCC to obtain a 10°C hysteresis
threshold) can directly control a cooling fan to improve the
heat transfer.
+5V
MCP1630
V IN
D1
Dn
V CC
V REF
GND
V
IN
V EXT
CS
FB
COMP
OSC IN
L
TC6501
GND GND HIST
T OVER