QUAD H-Bridge 40V Amplifier
Introduction
1
INTRODUCTION
The Delta Tau AMP-2 or QUAD H-Bridge Low Power Drive is a 3U-size amplifier designed to drive DC
brushed type motors in the UMAC system. This amplifier provides four 80W continuous PWM
amplifiers. The QUAD H-Bridge Low Power Drive may be interfaced conveniently to the PMAC
controller via ACC-24E2A. The maximum bus voltage for this amplifier is 40VDC and the continuous
rating for each drive is 2A.
The amplifiers on this product will output a current that is proportional to the voltage input. The
amplifier was designed to be used with torque or current command inputs from the controller but if the
controller has microstepping capabilities, the user can also use the product to drive stepper motors.
Power Supply Considerations
The QUAD H-Bridge Low Power Drive requires a single power supply of +15V to +40V max. The
current requirement can vary depending on the load, but should not exceed 12A (2A per channel)
continuous and 20A peak (4A per channel) for a one-second period. A slow blow 5A fuse is installed to
protect the shunt and a fast acting 15A fuse to protect the main bus.
The bus power supply can be provided to the amplifier unit through Amplifier Backplane board or
through the TB3 and TB4 terminal connectors located on the amplifier unit.
The amplifier receives its logic power supply (
±
15V) from an external power supply or the 3U power
supply used for a UMAC system via the Amplifier Backplane board (part number 603490 or 603470, see
last section of this manual).
If the amplifier is driven beyond its rated power, driver overheating may occur. In this event, the driver
will output a fault signal on the corresponding pin of Terminal Block 2 (TB2) and turn on the
corresponding red LED next to Terminal Block 1, TB1, shown in the Amplifier Layout Diagram.
Current Mode Considerations
The QUAD H-Bridge High Power Drive is a current amplifier with a fixed current gain 0.5A/V. This
means that the
±
10V signal input from each DAC on the J1 connector corresponds to
±
5A of current
across the load, provided that the bus supply voltage is not exceeded.
Note
If the amplifier is driving a DC motor at high speeds, the current supply to the
motor may be reduced if the back emf voltage of the motor is sufficiently large
(refer to the motor manufacture's data sheet).