CS7054YDWR16 ON Semiconductor, CS7054YDWR16 Datasheet - Page 6

• Manufacturer Part Number: CS7054YDWR16
• Description: IC CTRLR PWM FET LOW SIDE 16SOIC
• Manufacturer: ON Semiconductor

Specifications of CS7054YDWR16

• Applications: DC Motor Driver
• Number Of Outputs: 1
• Current - Output: 400mA
• Voltage - Supply: 8 V ~ 16 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (0.300", 7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Voltage - Load: -
• Other names: CS7054YDWR16OSTR

Oscillator
C
components R
to V
function properly. In order to keep the frequency of the
oscillator constant the current that charges C
vary with supply. R
C
therefore:
to the C
frequencies over the range of 15 Hz to 25 kHz. With the
suggested values of 105 k and 390 pF for R
respectively, the nominal frequency will be approximately
20 kHz. I
not change over a more than 2:1 ratio and therefore C
should be changed to adjust the oscillator frequency.
Voltage Duty Cycle Conversion
duty cycle at the OUTPUT lead. The transfer function
incorporates ON Semiconductor’s patented Voltage
Compensation method to keep the average voltage and
current across the load constant regardless of fluctuations in
the supply voltage. The duty cycle is varied based upon the
input voltage and supply voltage by the following equation:
OSC
OSC
The IC sets up a constant frequency triangle wave at the
The peak and valley of the triangle wave are proportional
This is required to make the voltage compensation
I
The period of the oscillator is:
The R
The IC translates an input voltage at the CTL lead into a
An internal DC voltage equal to:
ROSC
CC
. The voltage across R
lead whose frequency is determined by the external
by the following:
OSC
OSC
is multiplied by two (2) internally and transferred
ROSC
V DC + (1.683
T + 2C OSC
Duty Cycle + 100%
lead. Therefore:
and C
Frequency +
, at V
OSC
THEORY OF OPERATION
V VALLEY + 0.2
I ROSC + 0.5
V PEAK + 0.8
and C
OSC
CC
I COSC +"
OSC
= 14 V, will be 66.7 A. I
components can be varied to create
sets up the current which charges
OSC
V PEAK * V VALLEY
R OSC
V CTL ) ) V VALLEY
by the following equation:
OSC
R OSC
V CC
I COSC
0.83
R OSC
2.8
V CC
V CC
is 50% of V
V CC
C OSC
V CC
V CTL
APPLICATIONS INFORMATION
OSC
OSC
ROSC
and C
must also
CC
http://onsemi.com
should
OSC
OSC
and
CS7054
6
is compared to the oscillator voltage to produce the
compensated duty cycle. The transfer is set up so that at V
= 14 V the duty will equal V
example at V
duty cycle would be 50% at the output. This would place a
7.0 V average voltage across the load. If V
10 V, the IC would change the duty cycle to 70% and hence
keep the average load voltage at 7.0 V.
5.0 V Linear Regulator
V
for many internal and external functions. It has a drop out of
approximately 1.5 V at room temperature and does not
require an external capacitor for stability.
Current Sense and Timer
by cycle basis at the I
differential voltage across these two leads is amplified
internally and compared to the voltage at the I
gain, A
equation:
resistor (R
terminals and the voltage at the I
low pass filter which filters out high frequency noise
generated by the switching of the external MOSFET and the
associated lead noise. R
gain of the I
REG
There is a 5.0 V, 5.0 mA linear regulator available at the
The IC differentially monitors the load current on a cycle
The current limit (I
The R
120
100
80
60
40
20
0
10
A V +
lead for external use. This voltage acts as a reference
V
CS
, is set internally and externally by the following
SENSE
20
resistors and C
Figure 8. Voltage Compensation
LIM
I SENSE) * I SENSE*
I LIM +
CC
V
= 14 V, V
equation because the I
30
CC
) placed across the I
= 8.0 V
CTL Voltage (% of V
V I(ADJ)
1000 ) R CS
LIM
40
37000
CS
) is set by the external current sense
SENSE+
REG
CS
also forms an error term in the
50
components form a differential
= 5.0 V and V
CTL
V
CC
ADJ
60
and I
= 14 V
divided by V
R SENSE
lead.
+
V I(ADJ)
SENSE+
REG
SENSE+
70
SENSE–
1000 ) R CS
)
V
CC
CTL
CC
37000
80
ADJ
then drops to
and I
= 16 V
and I
= 2.5 V, the
leads. The
REG
lead. The
90
SENSE–
SENSE–
. For
100
CC