EVAL6730 STMicroelectronics, EVAL6730 Datasheet - Page 35

• Manufacturer Part Number: EVAL6730
• Description: EVAL BOARD FOR L6730XX
• Manufacturer: STMicroelectronics
• Type: Motor / Motion Controllers & Driversr

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

L6730 - L6730B
6.4
Compensation network
The loop is based on a voltage mode control
the internal/external reference voltage and scaled by the external resistor divider. The error
amplifier output V
pulse-width modulated (PWM) with an amplitude of V
is filtered by the output filter. The modulator transfer function is the small signal transfer
function of V
L-Cout resonance and a zero at F
Gain of the modulator is simply the input voltage V
voltage: V
Figure 29. Compensation network
The compensation network consists in the internal error amplifier, the impedance networks
Z
provide a closed loop transfer function with the highest 0dB crossing frequency to have
fastest transient response (but always lower than fsw/10) and the highest gain in DC
conditions to minimize the load regulation error. A stable control loop has a gain crossing the
IN
(R3, R4 and C20) and Z
OSC
OUT
.
/V
COMP
COMP
. This function has a double pole at frequency F
is then compared with the oscillator triangular wave to provide a
FB
Doc ID 11938 Rev 3
(R5, C18 and C19). The compensation network has to
Z
ESR
FB
depending on the output capacitor’s ESR. The DC
(Figure
IN
29). The output voltage is regulated to
divided by the peak-to-peak oscillator
IN
at the PHASE node. This waveform
Z
IN
LC
Application details
depending on the
35/52