EVAL6730 STMicroelectronics, EVAL6730 Datasheet - Page 17
![EVAL BOARD FOR L6730XX](/photos/9/30/93060/eval6730_sml.jpg)
EVAL6730
Manufacturer Part Number
EVAL6730
Description
EVAL BOARD FOR L6730XX
Manufacturer
STMicroelectronics
Type
Motor / Motion Controllers & Driversr
Datasheets
1.L6730TR.pdf
(52 pages)
2.L6730DTR.pdf
(50 pages)
3.EVAL6730.pdf
(9 pages)
4.EVAL6732.pdf
(43 pages)
Specifications of EVAL6730
Main Purpose
DC/DC, Step Down
Outputs And Type
1, Non-Isolated
Power - Output
66W
Voltage - Output
3.3V
Current - Output
20A
Voltage - Input
4.5 ~ 14V
Regulator Topology
Buck
Frequency - Switching
400kHz
Board Type
Fully Populated
Utilized Ic / Part
L6730
Input Voltage
8 V to 52 V
Product
Power Management Modules
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With/related Products
L6208
Other names
497-5501
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
In some conditions (short off-time, very low regulated current, high motor winding L / R) the system may need
an on-time shorter than 1.5µs. In these cases the PWM current controller can loose the regulation.
Figure 17 shows the operation of the circuit in this condition. When the current first reaches the threshold, the
bridge is turned off for a fixed time and the current decays. During the following on-time current increases above
the threshold, but the bridge cannot be turned off until the minimum 1.5µs on-time expires. Since current in-
creases more in each on-time than it decays during the off-time, it keeps growing during each cycle, with steady
state asymptotic value set by duty-cycle and load DC resistance: the resulting peak current will be
I
where D = t
Figure 17. Minimum on-time can cause the PWM controller to loose the regulation.
pk
= V
S
· D / R
ON
LOAD
/ (t
ON
,
+ t
OFF
) is the duty-cycle and R
LOAD
is the load DC resistance.
needed t
is about 1.5 µs
minimum t
than 1.5 µs
ON
AN1451 APPLICATION NOTE
is less
ON
V
ref
/ R
SENSE
17/43