Motorola M68HC08 manual Electrical Characteristics of the Optoisolation Board

Freescale Semiconductor, Inc.

Freescale Semiconductor, Inc.

Hardware Design

High-Voltage Hardware Set Components

250 ns for digital signals, and 2 ∝s for analog signals. Grounds are separated by the optocouplers’ galvanic isolation barrier.

Both input and output connections are made via 40-pin ribbon cable connectors. The pin assignments for both connectors are the same. For example, signal PWM_AT appears on pin 1 of the input connector and also on pin 1 of the output connector. In addition to the usual motor control signals, an MC68HC705JJ7CDW serves as a serial link, which allows controller software to identify the power board.

Power requirements for controller side circuitry are met with a single external 12-Vdc power supply. Power for power stage side circuitry is supplied from the power stage through the 40-pin output connector.

4.4.2.1 Electrical Characteristics of the Optoisolation Board

The electrical characteristics in Table 4-3apply to operation at 25°C, and a 12-Vdc power supply voltage.

Table 4-3. Electrical Characteristics

Characteristic	Symbol	Min	Typ	Max	Units	Notes
Power Supply Voltage	Vdc	10	12	30	V
Quiescent Current	ICC	70(1)	200(2)	500(3)	mA	dc/dc converter
Min Logic 1 Input Voltage	VIH	2.0	—	—	V	HCT logic
Max Logic 0 Input Voltage	VIL	—	—	0.8	V	HCT logic
Analog Input Range	VIn	0	—	3.3	V
Input Resistance	RIn	—	10	—	kΩ
Analog Output Range	VOut	0	—	3.3	V
Digital Delay Time	tDDLY	—	0.25	—	∝s
Analog Delay Time	tADLY	—	2	—	∝s

1.Power supply powers optoisolation board only.

2.Current consumption of optoisolation board plus DSP EMV board (powered from this power supply)

3.Maximum current handled by dc/dc converters

DRM028 — Rev 0		Designer Reference Manual
MOTOROLA	Hardware Design	69
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