EVDP610 Datasheet, PDF (3/6 Pages) IXYS Corporation – IXDP610 Digital PWM Controller IC Evaluation Board

the user can choose between three different PWM base
periods for any given external CLOCK frequency.
When the IXDP610 is programmed in 8-bit mode, the
PWM base period is equal to 256 PWM clock cycles.
In 7-bit mode the PWM base period is equal to 128
PWM clock cycles. A PWM clock cycle is equal to
one external CLOCK period when the clock is divided
by one. The following formulas can be used to deter-
mine the PWM base period:
If 7-bit resolution and clock divide by 1 -> PWM base
period = CLOCK period x 128
If 8-bit resolution and clock divide by 1 -> PWM base
period = CLOCK period x 256
If 7-bit resolution and clock divide by 2 -> PWM base
period = CLOCK period x 256
If 8-bit resolution and clock divide by 2 -> PWM base
period = CLOCK period x 512
2.2.5 Stop
This bit in the control latch of the IXDP610 enables and
disables the outputs. When enabled, the outputs will
not be re-enabled until the start of the PWM period.
2.2.6 ODIS : Output Disable
Referred to as the OUPUT DISABLE pin, this pin on the
IXDP610 is connected to a jumper on the board (labeled
JP2), which is tied to a pull-up resistor before the
jumper is installed. Installing a jumper onto these pins
asserts the ODIS pin (ties the pull-up to ground putting
a low signal onto ODIS). Asserting ODIS, or the
OUTPUT DISABLE pin, on the IXDP610 forces the
complementary outputs to be immediately disabled
(forced low). These outputs will remain low as long as
this input is asserted, and for the duration of the PWM
cycle in which OUTPUT DISABLE goes from low to
high; i.e., the complementary outputs are not re-
enabled until the beginning of the next PWM cycle, and
then only if the both ODIS and Stop are not enabled.
*For more information on technical specifications of the
IXDP610 IC, please see the IXDP610 documentation
which can be downloaded from the IXYS website
(www.ixys.com).
2.2 Outputs
The IXDP610 chip, labeled U1 on the evaluation board,
and its complementing outputs (labeled TP1 and TP2)
can be accessed either with the black and white
terminals provided or by J4, which accommodates a
four pin header. Pin one and three on the header are
the output signals and pins 2 and 4 are connected to
EVDP610
ground. Pin 1 on the board is indicated by the square
via. This provides easy access for outside wires or a
wiring harness to connect to another board.
2.3 Input Clock Selection and Jumper Settings
The evaluation board has 3 jumper settings (labeled JP1
on the board) that allow the user to switch between three
input clock selections:
1) Using the microprocessor to clock the IXDP610.
2) Using the on-board 11.059 MHz to clock the
IXDP610.
3) Hooking up an external clock signal. For this
either wire the clock signal to the jumper itself
or the user can use the TP3 via.
Figure 5 shows the placement of the jumper for each
setting. Factory default is the middle setting, clocking
the IXDP610 with the on-board 11.059MHz oscillator.
Figure 5: Placement of Jumper for IXDP610
Clock Selection
2.3.1 Using the Microprocessor as the Input Clock
The microprocessor on the evaluation board can be used
as the clock signal into the IXDP610. This clock can
provide output frequencies of 1 – 50 Hz on the IXDP610
chip. Due to interrupt latency this is as fast as the
microprocessor can clock the IXDP610 and there is a +/-
3% frequency error associated with this arrangement.
2.3.2 Using the 11.059 MHz as the Input Clock
This is set as the factory default; it allows the same on-
board oscillator that clocks the microprocessor to clock
the IXDP610.
2.3.3 Using an External Clock Signal
Allowing the user to hook up an external clock signal
allows any input clock (up to 50 MHz) to be used as
input to the IXDP610. This results in output frequencies
3