E910.72A61DC ELMOS Semiconductor, E910.72A61DC Datasheet - Page 30

• Manufacturer Part Number: E910.72A61DC
• Description: Motor / Motion / Ignition Controllers & Drivers 6x HVAC motor driver/pulse count
• Manufacturer: ELMOS Semiconductor
• Type: DC Motor 6x Half Bridger

Specifications of E910.72A61DC

• Rohs: yes
• Product: Brushed DC Motor Drivers
• Operating Supply Voltage: 5 V
• Supply Current: 3 mA
• Operating Temperature: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFN-32
• Number Of Outputs: 5
• Output Current: 100 mA
• Output Voltage: 6 V to 19 V
• Power Dissipation: 1 W

When the motor gets started or braked, or when transients on supply voltage or load appear, the average motor
current changes rapidly, and these transients can be higher than the ripple signal to be detected. These conditions
are shown in Fig. 10 for a motor start as an example. What is still visible under these conditions are the rapid cur-
rent drops on every commutation.
Based on the different signal shapes the ripple detection circuit features two different signal paths to realise safe
recognition under all conditions. One signal path, called pulse detection, reacts on the rapid current drop, while
the other signal path, called sine wave detection, reacts on AC components that are more sinusoidally shaped. An
arbitration is implemented to avoid interference of the two paths.
Commutation points can only be detected, if the current signal shape fulfil the specification. For pulses a maxi-
mum fall time t
sary. For sine pulses a maximum sine frequency f
5.4.3 Current Measurement
Current is measured as voltage drop across the on resistance of a half bridge's low side driver. When the motor
brakes, both low side drivers of a full bridge are turned on. The generator voltage of the motor reverses current. So
to get a positive voltage for measurement, the detection input is switched to the other transistor.
It is necessary to adapt the gain of the input amplifier to the current that the specific type of motor draws from
the supply. The highest possible gain that does not override the amplifier should be selected. Three different gain
settings (low, medium, high) can be selected via SPI. For each motor an individual gain can be chosen in the re-
lated ripple detection block. Therefore, different types of motors can be connected to the IC. Motor stall current
at maximum battery voltage (e.g. 18 V) must not exceed the values given in chapter 'Ripple Detection - DC Char-
acteristics'.
During normal operation switching into brake mode is only possible immediately after a ripple signal has been de-
tected by either the pulse detection or the sine wave detection. A debounce of typically 1ms after the rising edge
of the digitised signal is implemented in order to avoid multiple pulses caused by commutator noise, as well as
unintended counting on the transition from run to brake mode.
5.4.4 stall Detection
If the motor gets stalled no ripple signals are detected. A timeout of typically 200ms is implemented to switch the
motor off, i.e. into brake mode. A diagnostic signal "Motor Stall" is stored and can be read out together with the
position information.
5.4.5 actuator positioning
The four actuator positioning parameters motor address, direction, number of counts and the gain have to be
transferred via the SPI. The IC activates the corresponding two half bridges and counts commutation pulses until
the required number is reached. The motor will then be braked by activating both low side drivers, still counting
commutation pulses. Motor stop is detected when no ripple pulses have occurred for typically 100ms.
After the motor has stopped the output DRB is activated and the actual number of counts can be read back from
the SPI. This number will normally be higher than the required one since in brake mode the motor delivers an un-
predictable number of additional pulses. This number is relatively small, so there is no reason to try to correct it by
moving the motor back. Some compensation can be implemented into the control unit by reducing the required
DC Motor 6 x Half briDgE witH ripplE CoUnt
aDVanCE proDUCt inforMation - MaY 05, 2011
ELMOS Semiconductor AG
FALL
, a minimum length t
PULSEWIDTH
of around t
SIN
and a minimum peak peak value I
Data Sheet
30/34
PL,MAX
and a minimum drop amplitude I
SIN,PP,MAX
QM-No.: 25DS0057E.00
is necessary.
DR,NEG,MAX
E910.72
is neces-