LTC3636IUFD-1-PBF 查看數據表（PDF） - Linear Technology
零件编号
产品描述 (功能)
生产厂家
LTC3636IUFD-1-PBF Datasheet PDF : 28 Pages
| |||
LTC3636/LTC3636-1
Pin Functions
ITH1 (Pin 1): Channel 1 Error Amplifier Output and
Switching Regulator Compensation Pin. Connect this pin
to appropriate external components to compensate the
regulator loop frequency response. Connect this pin to
INTVCC to use the default internal compensation.
RUN1 (Pin 2): Channel 1 Regulator Enable Pin. Enables
channel 1 operation by tying RUN above 1.25V. Tying it
below 1V places the part into shutdown. Do not float this pin.
MODE/SYNC (Pin 3): Mode Select and External Synchro-
nization Input. Tie this pin to ground to force continuous
synchronous operation. Floating this pin or tying it to
INTVCC enables high efficiency Burst Mode operation at
light loads. Drive this pin with a clock to synchronize the
LTC3636/LTC3636-1 switching frequency. An internal
phase-locked loop will force the bottom power NMOS’s
turn on signal to be synchronized with the rising edge of
the CLKIN signal. When this pin is driven with a clock,
forced continuous mode is automatically selected.
RT (Pin 4): Oscillator Frequency Program Pin. Connect an
external resistor (between 80k to 640k) from this pin to
GND in order to program the frequency from 500kHz to
4MHz. When RT is tied to INTVCC, the switching frequency
will default to 2MHz.
INTVCC (Pin 5): Internal 3.3V Regulator Output. The inter-
nal power drivers and control circuits are powered from
this voltage. Decouple this pin to power ground with a
minimum of 4.7µF low ESR ceramic capacitor.
TMON (Pin 6): Temperature Monitor Output. A voltage
proportional to the measured on-die temperature will ap-
pear at this pin. The voltage-to-temperature scaling factor
is 200°K/V. See the Applications Information section for
detailed information on the TMON function. Tie this pin to
INTVCC to disable the temperature monitor circuit.
RUN2 (Pin 7): Channel 2 Regulator Enable Pin. Enables
channel 2 operation by tying RUN above 1.22V. Tying it
below 1V places the part into shutdown. Do not float this pin.
ITH2 (Pin 8): Channel 2 Error Amplifier Output and
Switching Regulator Compensation Pin. Connect this pin
to appropriate external components to compensate the
regulator loop frequency response. Connect this pin to
INTVCC to use the default internal compensation.
VFB2 (Pin 9): Channel 2 Output Feedback Voltage Pin.
Input to the error amplifier that compares the feedback
voltage to the internal 0.6V reference voltage. Connect this
pin to a resistor divider network to program the desired
output voltage.
PGOOD2 (Pin 10): Channel 2 Open-Drain Power Good
Output Pin. PGOOD2 is pulled to ground when the voltage
on the VFB2 pin is not within ±8% (typical) of the internal
0.6V reference. PGOOD2 becomes high impedance once
the VFB2 pin returns to within ±5% (typical) of the internal
reference.
TRACKSS2 (Pin 11): Output Tracking and Soft-Start Input
Pin for Channel 2. Forcing a voltage below 0.6V on this pin
bypasses the internal reference input to the error amplifier.
The LTC3636/LTC3636-1 will servo the FB pin to the TRACK
voltage. Above 0.6V, the tracking function stops and the
internal reference resumes control of the error amplifier.
An internal 1.4μA pull up current from INTVCC allows a
soft-start function to be implemented by connecting a
capacitor between this pin and PGND.
GND (Pins 12, 18, 19, 25): Power and Signal Ground. These
pins must be tied together and soldered to PCB ground.
SW2 (Pins 13, 17): Channel 2 Switch Node Connection
to External Inductor. Voltage swing of SW is from a diode
voltage drop below ground to VIN.
BOOST2 (Pin 14): Boosted Floating Driver supply for
Channel 2. The (+) terminal of the bootstrap capacitor
connects to this pin while the (–) terminal connects to
the SW pin. The normal operational voltage swing of this
pin ranges from a diode voltage drop below INTVCC up
to VIN+INTVCC.
3636fa
8
For more information www.linear.com/LTC3636
Share Link: 