Sharp LC-32LE511E, Руководство по обслуживанию

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32
LC-32LE511
LC-40LE511
LC-40LE531
15
.
Pin Configuration
Figure 3. MLP 5x6mm Pin Configuration (Bottom View)
Pin Definitions
Pin # Name Description
P1, 6-12 SW Switching Node . Junction of high-side and low-side MOSFETs.
P2, 2-5 VIN Power Input Voltage . Connect to the main input power source.
P3, 21-23 PGND Power Ground . Power return and Q2 source.
1 BOOT
High-Side Drive BOOT Voltage . Connect through capacitor (C
BOOT
) to SW. The IC
includes an internal synchronous bootstrap diode to recharge the capacitor on this pin to
V
CC
when SW is LOW.
13 PGOOD
Power-Good Flag . An open-drain output that pulls LOW when FB is outside the limits
specified in electrical specs. PGOOD does not assert HIGH until the fault latch is enabled.
14 EN
ENABLE . Enables operation when pulled to logic HIGH or left open. Toggling EN resets the
regulator after a latched fault condition. This input has an internal pull-up when the IC is
functioning normally. When a latched fault occurs, EN is discharged by a current sink.
15 VCC
Input Bias Supply for IC . The IC’s logic and analog circuitry are powered from this pin.
This pin should be decoupled to AGND through a >1µF X5R/X7R capacitor.
16 AGND
Analog Ground . The signal ground for the IC. All internal control voltages are referred to
this pin. Tie this pin to the ground island/plane through the lowest impedance connection.
17 ILIM
Current Limit . A resistor (R
ILIM
) from this pin to AGND can be used to program the current-
limit trip threshold lower than the default setting.
18 R(T)
Oscillator Frequency . A resistor (R
T
) from this pin to AGND sets the PWM switching
frequency.
19 FB Output Voltage Feedback . Connect through a resistor divider to the output voltage.
20 COMP
Compensation . Error amplifier output. Connect the external compensation network
between this pin and FB.
24 NC No Connect . This pin is not used.
25 RAMP
Ramp Amplitude . A resistor (R
RAMP
) connected from this pin to VIN sets the ramp
amplitude and provides voltage feedforward functionality.