The LMR36500 is the industry smallest 65-V, 50-mA synchronous step-down DC/DC converter in 4-mm2 HotRod package. This easy-to-use converter can handle input voltage transients up to 70 V, provide excellent EMI performance and supports fixed, 3.3 V, 5 V and other adjustable output voltages.
The LMR36500 uses a peak current mode control architecture with internal compensation to maintain stable operation with minimal output capacitance. The LMR36500 with the right resistor selection from the RT pin to ground can be externally programmed to any desired switching frequency of operation over a wide range from 200 kHz to 2.2 MHz. The precision EN/UVLO feature allows precise control of the device during start-up and shutdown. The PGOOD flag, with built-in glitch filter and delayed release, offers a true indication of the system status, eliminating the requirement for an external voltage supervisor. The compact design size and rich feature set of LMR36500 simplifies implementation for a wide range of industrial applications.
PART NUMBER | PACKAGE (1) | PACKAGE SIZE(2) |
---|---|---|
LMR36500 | RPE (VQFN-HR, 9) | 2.00 mm × 2.00 mm |
ORDERABLE PART NUMBER (1) | RATED CURRENT | OUTPUT VOLTAGE | EXTERNAL SYNC | FSW | SPREAD SPECTRUM |
---|---|---|---|---|---|
LMR36500P3RPE | 50 mA | Fixed 3.3-V / Adjustable | No (Default PFM at light load) |
Adjustable with RT resistor |
No |
LMR36500P5RPE(2) | 50 mA | Fixed 5-V / Adjustable | No (Default PFM at light load) |
Adjustable with RT resistor |
No |
LMR36500F3RPE | 50 mA | Fixed 3.3-V / Adjustable | No (Default FPWM at light load) |
Adjustable with RT resistor |
No |
LMR36500F5RPE(2) | 50 mA | Fixed 5-V / Adjustable | No (Default FPWM at light load) |
Adjustable with RT resistor |
No |
PIN | TYPE | DESCRIPTION | ||
---|---|---|---|---|
NO. | NAME | |||
1 | RT | A | The switching frequency can be adjusted from 200 kHz to 2.2 MHz by selecting the appropriate valued resistor from this pin to GND. See Section 7.3.2 for more details. Do not float this pin. | |
2 | PGOOD | A | Open-drain power-good flag output. Connect to suitable voltage supply through a current limiting resistor. High = power OK, low = power bad. This pin goes low when EN = low. This pin can be open or grounded when not used. | |
3 | EN/UVLO | A | Enable input to regulator. High = ON, Low = OFF.
Can be connected directly to VIN. Do not float this pin. | |
4 | VIN | P | Input supply to regulator. Connect a high-quality bypass capacitor or capacitors directly to this pin and GND. | |
5 | SW | P | Regulator switch node. Connect to power inductor. | |
6 | BOOT | P | Bootstrap supply voltage for internal high-side driver. Connect a high-quality 0.1-μF capacitor from this pin to the SW pin. | |
7 | VCC | P | Internal LDO output. Used as supply to internal control circuits. Do not connect to external loads. Can be used as logic supply for power-good flag. Connect a high-quality 1-µF capacitor from this pin to GND. | |
8 | VOUT/FB | A | Fixed output options and adjustable output
options are available with the VOUT/FB pin variant. Connect to the output voltage
node for fixed VOUT. Connect to tap point of feedback voltage divider for
adjustable VOUT. See Output Voltage
Selection for how to select feedback resistor divider values. Check
Device Comparison Table for more details. Do not float this pin. | |
9 | GND | G | Power ground terminal. Connect to system ground. Connect to CIN with short, wide traces. | |
A = Analog, P = Power, G = Ground |