ASTROSYN P808 Service Manual

A

Users Manual

For P808

High Performance Microstepping Driver

Thank you for purchasing the Astrosyn P808 drive.
Please read this manual thoroughly before installing and operating
the driver, and always keep the manual where it is readily
accessible.

The Old Courthouse, New Road Avenue, Chatham, Kent, ME4 6BE England

Telephone: [phone] Fax: [phone]

Registered office: Montague Place, Quayside, Chatham Maritime, Kent, ME4 4QU Registered in England No. 1188550

Email: [e-mail]

strosyn International Technology Ltd

Ltd

Web: http// www.astrosyn.com

Table of Contents

Page

1. General 1

¾ Features of the Driver 1

¾ Applications of the Driver 1

2. Specifications and Operating Environment 2

¾ Electrical Specifications 2

¾ Operating Environment and Parameters 2

3. Driver Connectors, P1 and P2 3

¾ Control Signal Connector P1 Pins 3

¾ Power Connector P2 Pins 3

4. Power Supply Selection 4

¾ Maximum Voltage Input 4

¾ Regulated or Unregulated Power Supply 4

¾ Multiple Drivers 4

5. Driver Voltage and Current Selection 5

¾ Selecting Supply Voltage 5

¾ Setting Proper Output Current 5

6. Microstep Resolution and Driver Current Output 6

¾ Microstep Resolution Selection 6

¾ Current Setting 6

¾ DIP Setting for current during motion 6

¾ DIP Setting for current during Standstill 6

7. Control Signal Connector (P1) Interface 7

8. Driver Connection to Stepper Motors 8

9. Connection Diagram 9

10. Control Signal Waveform and Timing 10

11. Drive Dimensions 11

1. GENERAL

The P808 is a high performance microstepping driver based on the most advanced
technology in the world today.
It is suitable for driving any 2-phase and 4-phase hybrid stepping motors (Current

7.7A).

By using advanced bipolar constant-current chopping techniques, it can output
more speed and power from the same motor, compared with traditional
technologies such as L/R drivers. It has patented current control technology, which
allows coil currents to be accurately controlled, generating much less current ripple
and motor heating than other drivers on the market.

Features of this Driver:

¾ High Performance, low cost
¾ Supply voltage to +90VDC, current to 7.7A for P808
¾ Inaudible 20khz chopping frequency
¾ TTL compatible and optically isolated input signals
¾ Automatic idle-current reduction
¾ Mixed-decay current control for less motor heating
¾ 14 Selectable step resolutions in decimal and binary
¾ Microstep resolutions up to 51,200 steps/rev
¾ Suitable for 4, 6 or 8 lead motors
¾ Over-current, over-voltage and short-circuit protection
¾ Small size

Applications of this Driver:

Suitable for a wide range of stepping motors of Size NEMA 17, 23, 34 and 42.
Usable for various kinds of machines, such as X – Y Tables, labelling machines,
laser cutters, engraving machines, and pick-place devices; particularly useful in
applications with low noise, low vibration, high speed and high precision
requirements.

Page 1

2. SPECIFICATIONS AND OPERATING ENVIRONMENT

Electrical Specifications (T = 25°C)

P808

Parameters Min Typical Max Remark
Peak Output Current 2.8A By User 7.7A By DIP Switch
Supply Voltage (DC) +24V +68V +90V
Logic Signal Current 6mA 10mA 30mA
Pulse Input Frequency 0 By User 300 kHz
Isolation Resistance

Operating Environment and Parameters

500MΩ

Coolant Natural Cooling or Forced convection
Environment Space Avoid water, dust, oil, frost and corrosive

gases

Temperature

0° to 50°C
Humidity 40 to 90%RH
Vibration 5.9m/s2Max
Storage Temp.

-20 °C to +65°C

Weight About 0.45Kg

Page 2

3 DRIVER CONNECTORS, P1 AND P2

The following is a brief description of the two connectors of the Driver. More
detailed descriptions of the pins and related issues are presented in Sections 4
and 6 – 9.

Control Signal Connector P1 Pins

Pin

Signal Functions
No.
1 Pul + (+5V)
2 Pul - (Pulse)

Pulse Signal
input represents pulse signal, effective for each upward-

: In single pulse (Pulse/direction) mode, this

rising edge; in double pulse mode (Pulse/pulse) this input
represents clockwise (CW) pulse. For reliable response,

pulse width should be longer than 3µs
3 Dir + (+5V)
4 Dir - (Dir)

Direction Signal

: In single pulse mode, this signal has
low/high voltage levels, representing two directions of
motor rotation; in double-pulse mode (set by inside
jumper JMPI), this signal is counter-clock (CCW) pulse,
effective on each rising edge. For reliable motion
response, direction signal should be sent to driver 2µs
before the first pulse of a motion direction reversal.

5 Ena + (+5V)
6 Ena - (Ena)

Enable Signal:
level for enabling driver and low level for disabling driver.

this signal is used for enable/disable, high

Usually left unconnected (Enabled)

Remark 1:

Pul/dir is the default mode; internal jumper JMPI can be used to

switch to CW/CCW double-pulse mode.

Remark 2

: Please note motion direction is also related to motor-driver wiring
match. Exchanging the connection of two wires for a coil to the driver will reverse
motion direction. (For example, reconnecting motor A+ to driver A- and motor A­to driver A+ will invert motor direction).

Power Connector P2 Pins

Pin No. Signal Functions
1 Gnd DC Power Ground
2 + V DC Power Supply, +24VDC + 90VDC, Including voltage

fluctuation and EMF voltage.
3, 4 Phase A Motor coil A (leads A + and A - )
5, 6 Phase B Motor coil B (leads B + and B - )

Page 3

4 POWER SUPPLY SECTION

It is important to choose the appropriate power supply to make the driver operate
properly.

Maximum Voltage Input:

The power Mosfet inside the driver can actually operate within +24V to +90VDC,
including power input fluctuation and back EMF voltage generated by motor coils
during motor shaft deceleration.

Higher voltage will damage the driver. Therefore, it is suggested to use power
supplies with theoretical output voltage of no more than +85V, leaving room for
power line fluctuation and back EMF

Regulated or unregulated power supply:

Both regulated and unregulated power supplies can be used to supply DC power
to the driver. However, unregulated power supplies are preferred due to their
ability to withstand current surge. If regulated power supply (Such as most
switching supplies.) is indeed used, it is important to have large current output
rating to avoid problems like current clamp, for example using 4A supply for 3A
motor-driver operation. On the other hand, one may use a power supply of lower
current rating than that of motor (typically 50% ~ 70% of motor current). The
reason is that the driver draws current from the power supply capacitor only
during the ON duration of the PWM cycle, but not during OFF duration.
Therefore, the average current withdrawn from power supply is considerably less
than motor current. For example, two 3A motors can be well supplied by one
power supply of 4A rating.

Multiple Drivers:

It is recommended that multiple drivers share one power supply to reduce cost,
provided that the supply has enough capacity. DO NOT daisy-chain the power
supply input pin of the drivers (Connect them to power supply separately) to avoid
cross interference.
Higher supply voltage will allow higher motor speed to be achieved, at the price of
more noise and heating. If the motion speed requirement is low, it is better to use
lower supply voltage to improve noise, heating and reliability.
NEVER

connect power and ground in the wrong, it will damage the driver.

Page 4

5 DRIVER VOLTAGE AND CURRENT SELECTION

This driver can match small-medium size step motors (NEMA 17, 23, 34 and 42).

To achieve good driving results, it is important to select supply voltage and output
current properly. Generally, supply voltage determines the high-speed
performance of the motor, while output current determines the output torque of the
motor (particularly at lower speed).

Selecting Supply Voltage:

Higher supply voltage can increase motor torque at higher speeds; this is helpful
for avoiding losing steps. However, higher voltage may cause more motor
vibration at lower speed, and it may also cause over-voltage protection and even
driver damage.
Therefore, it is suggested to choose only sufficiently high supply voltage for
intended applications.

Setting Proper Output Current

For a given motor, higher driver current will make the motor to output more torque,
but at the same time causes more heating in the motor and driver. Therefore,
output current is generally set to be such that the motor will not overheat during
lengthy operation.
Since parallel and serial connections of motor coils will significantly change
resulting inductance and resistance, it is important to set driver output current
depending on motor phase current, motor leads and connection methods.
Phase current rating supplied by motor manufacturer is important in selecting
driver current, but the selection also depends on leads and connection.

Page 5

6. MICROSTEP RESOLUTION AND DRIVER CURRENT OUTPUT

This driver uses an 8-bit DIPswitch to set microstep resolution, dynamic current and
standstill current, as shown below:

Current during motion Microstep resolution

2 1

6 7 8543

Standstill current (half/full)

Microstep Resolution Selection
Microstep Resolution is set by SW5, 6, 7, 8 as shown in the following table:

Microstep

Step/Rev (For 1.8°Motor)

SW5 SW6 SW7 SW8
0 No rotation Off Off Off Off
2 400 On On On On
4 800 On Off On On
8 1600 On On Off On

16 3200 On Off Off On
32 6400 On On On Off

64 12800 On Off On Off
128 25600 On On Off Off
256 51200 On Off Off Off

5 1000 Off On On On
10 2000 Off Off On On
25 5000 Off On Off On
50 10000 Off Off Off On

125 25000 Off On On Off
250 50000 Off Off On Off

Current Setting

The first three bits (SW1, 2, 3) of the DIP switch are used to set the current during
motion (dynamic current), while SW4 is used to select standstill current.

P808 DIP Selection for current during motion:

Current for P808 SW1 SW2 SW3

2.8A On On On

3.5A Off On On

4.2A On Off On

4.9A Off Off On

5.7A On On Off

6.4A Off On Off

7.0A On Off Off

7.7A Off Off Off

Note that due to motor inductance, actual coil current may be smaller than dynamic
current settings, particularly at higher speeds.

DIP Setting for current during standstill:

SW4 is used for this purpose, current setting due to coil inductance. OFF
meaning that the standstill current is set to be half of the dynamic current and ON
meaning that standstill current is set to be the same as the dynamic current.

Page 6

7 CONTROL SIGNAL CONNECTOR (P1) INTERFACE

This driver uses differential inputs to increase noise immunity and interface
flexibility. Single-ended control signals from the indexer/controller can also be
accepted by this interface. The input circuit has built-in high-speed optocoupler,
and can accept signals in the format of line driver, open-collector, or PNP output.
Line driver (differential) signals are suggested for reliability. In the following
figures, connections to open-collector and PNP signals are illustrated.

PNP Output (common anode)

Open-Collector Signal (Common -)

Page 7

8 DRIVER CONNECTION TO STEP MOTORS

The P808 driver can drive any 4, 6, or 8 lead hybrid stepper motors. The following
diagrams illustrate connection to various kinds of motor leads:

Note that when two coils are connected in parallel, coil inductance is reduced by half
and motor speed can be significantly increased. Serial connection will lead to
increased inductance and thus the motor can be run well only at lower speeds.

Page 8

9 CONNECTION DIAGRAM

A complete stepping system should include stepping motor, stepping driver, power
supply and controller (pulse generator).

A typical connection is shown below:

Page 9

10 CONTROL SIGNAL WAVEFORM AND TIMING

This driver can accept pulse control signals up to 300khz.

Before a direction reversal, the direction signal needs to be established at least 2 µs
before the first pulse of the next pulse train. Please examine the timing diagrams of
the three control signals as follows:

Page 10

11. DRIVE DIMENSIONS

External Dimensions are shown in mm

120

102

50

8

Page 11