User`s manual

PK2200 Subsystems s 27

Digital Outputs

The PK2200s 14 digital outputs (HV01 through HV14) provide high-

voltage, high-current digital outputs for your application. Sinking and

optional sourcing drivers will drive a variety of loads including inductive

loads such as relays, small solenoids, or stepping motors.

Note the following points regarding the digital outputs:

 Each output is individually addressable.

 Each output includes a protective diode that returns inductive

spikes to the power supply.

 Sinking drivers are standard. Sourcing drivers are optional. Both

drivers must be of the same type, either sinking or sourcing.

The total number of outputs that can be on simultaneously is subject to

chip power limits and ambient temperature. There are power limitations

on each channel as well as the entire driver IC. Eight channels, HV1

HV8, are driven by one driver IC. The other six, HV9HV14, are driven

by the other driver IC. Since fewer outputs are being driven by the HV9

HV14 driver IC, the current limit on these channels is higher than on the

HV1HV8 channels.

Figure 3-5 illustrates the configuration for the ULN2803 sinking driver.

Figure 3-5. Sinking Driver Configuration

Note the following points regarding the ULN2803 sinking driver chip.

 Outputs pull low (sink current) when turned on.

 The chips rating is 48 V and 500 mA maximum per channel,

subject to the chips thermal limits and ambient temperature.

 With all channels on, each channel can sink up to 170 mA

continuously (100% duty cycle) as long as the chip temperature is

less or equal to 50°C. At 70°C the current must be reduced to

140 mA or less.

inductive

load

Channel (



14)

external

ULN2803

JP1

HV01HV14