MAX32600 User’s Guide
Analog Front End
8.5 LED
8.5.2.9.1
LED Matrix Limitations
The matrix system limitations depend in part on the diode; a high peak current rating is required. There are eight available pulldowns and 48 available pullups (if
no I/O is reserved for other purposes), yielding a theoretical maximum array size of 384 LEDs. This maximum array, however, would be very dim under any type of
control; arrays would have to be significantly smaller to have practical usage.
Typically, small LED module sizes are in multiples of 5x7 pixels and have high peak currents per diode to enable low duty cycle operation. Here, although a 5x7 array
only requires five pulldowns and seven pullups for operation, doubling the pullups is recommended for optimal performance. A total of five pulldown pairs and 14
pullups are then needed.
8.5.3
Register Configurations
To configure the
MAX32600
for these
, several sets of registers must be written:
• Request current mode usage from I/O mux
• Configure the control loop in the AFE
• If needed, configure any comparators used for fault detection
• If needed, configure TIAs and the ADC for measurement
• Set up the pulse trains or timers
8.5.3.1
Current Mode Request
Note
See
for a detailed mapping of
MAX32600
multiplexed function locations. Functional priority distinction is included in the mapping.
Mapping of Logical Current Ports (7mm x 7mm Compact Package)
Sink Port
Switch Drain
Switch Source
Drive
Feedback
CS0
P0.0
P0.1
2X
0
CS1
P0.2
P0.3
2X
1
CS2
P0.4
P0.5
4X
0
CS3
P0.6
P0.7
3X
1
Rev.1.3 April 2015
Maxim Integrated
Page 482
Содержание MAX32600
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