STEVAL-PSQ001V1 STMicroelectronics, STEVAL-PSQ001V1 Datasheet - Page 22

• Manufacturer Part Number: STEVAL-PSQ001V1
• Description: BOARD EVAL BASED ON PM6680A
• Manufacturer: STMicroelectronics
• Type: Other Power Managementr

Specifications of STEVAL-PSQ001V1

• Design Resources: STEVAL-PSQ001V1 Gerber Files STEVAL-PSQ001V1 Schematic STEVAL-PSQ001V1 Bill of Material
• Main Purpose: DC/DC, Step Down with LDO
• Outputs And Type: 6, Non-Isolated
• Voltage - Output: 0.9 ~ 2.5 V, 1 ~ 3.3 V, 2x 3.3 V, 2.5 V, 5 V
• Current - Output: 4A, 2A, 800mA, 400mA, 400mA, 150mA
• Voltage - Input: 5 ~ 36V
• Regulator Topology: Buck
• Frequency - Switching: 200kHz, 300kHz
• Board Type: Fully Populated
• Utilized Ic / Part: PM6680A
• Input Voltage: 5 V to 36 V
• Output Voltage: 1 V to 3.3 V
• Product: Power Management Modules
• Silicon Manufacturer: ST Micro
• Silicon Core Number: PM6680A
• Kit Application Type: Power Management
• Application Sub Type: Power Supply
• Kit Contents: Board
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• For Use With/related Products: PM6680A
• Other names: 497-6425; STEVAL-PSQ001V1

Device description
7.4
22/48
Pulse skip mode
If the SKIP pin is tied to ground, the device works in skip mode.
At light loads a zero-crossing comparator truncates the low-side switch on-time when the
inductor current becomes negative. In this condition the section works in discontinuous
conduction mode. The threshold between continuous and discontinuous conduction mode
is:
Equation 5
For higher loads the inductor current doesn’t cross the zero and the device works in the
same way as in PWM mode and the frequency is fixed to the nominal value.
Figure 31.
Figure 31
average inductor current equal to load current, in SKIP mode some switching cycles are
skipped. When the output ripple reaches the regulated voltage Vreg, a new cycle begins.
The off cycle duration and the switching frequency depend on the load condition.
As a result of the control technique, losses are reduced at light loads, improving the system
efficiency.
shows inductor current waveforms in PWM and SKIP mode. In order to keep
PWM and pulse skip mode inductor current
ILOAD SKIP
(
)
=
V
----------------------------- -
IN
2
–
×
V
L
OUT
×
T
ON
PM6680A