ZHCSMX3C December 2020 – February 2023 LM5149-Q1
PRODUCTION DATA
#GUID-52EC63DC-57F7-477E-9B04-A935B2CFB2B9/SNVSB29621 shows the intended input, output, and performance parameters for this automotive design example. Reference the LM25149-Q1EVM-2100 evaluation module.
DESIGN PARAMETER | VALUE |
---|---|
Input voltage range (steady-state) | 8 V to 18 V |
Min transient input voltage (cold crank) | 5.5 V |
Max transient input voltage (load dump) | 36 V |
Output voltage | 5 V |
Output current | 8 A |
Switching frequency | 2.1 MHz |
Output voltage regulation | ±1% |
Standby current, no-load | 12 µA |
Shutdown current | 2.3 µA |
Soft-start time | 3 ms |
The switching frequency is set at 2.1 MHz by resistor RRT. In terms of control loop performance, the target loop crossover frequency is 60 kHz with a phase margin greater than 50°.
The selected buck regulator powertrain components are cited in #GUID-52EC63DC-57F7-477E-9B04-A935B2CFB2B9/SNVSB29622, and many of the components are available from multiple vendors. The MOSFETs in particular are chosen for both lowest conduction and switching power loss, as discussed in detail in Power MOSFETs. This design uses a low-DCR metal-powder composite inductor and ceramic output capacitor implementation.
REFERENCE DESIGNATOR | QTY | SPECIFICATION | MANUFACTURER | PART NUMBER |
---|---|---|---|---|
CIN | 2 | 10 µF, 50 V, X7S, 1210, ceramic, AEC-Q200 | Taiyo Yuden | UMJ325KB7106KMHT |
Murata | GCM32EC71H106KA03 | |||
TDK | CGA6P3X7S1H106K250AB | |||
CO | 4 | 47 µF, 6.3 V, X7R, 1210, ceramic, AEC-Q200 | Murata | GCM32ER70J476KE19L |
Taiyo Yuden | JMK325B7476KMHTR | |||
47 µF, 10 V, X7S, 1210, ceramic, AEC-Q200 | TDK | CGA6P1X7S1A476M250AC | ||
LO | 1 | 0.68 μH, 2.9 mΩ, 15.3 A, 6.7 × 6.5 × 3.1 mm, AEC-Q200 | Coilcraft | XGL6030-681MEB |
0.56 μH, 3.6 mΩ, 13 A, 6.6 × 6.6 × 4.8 mm, AEC-Q200 | Würth Electronik | 744373490056 | ||
0.68 µH, 4.5 mΩ, 22 A, 6.95 × 6.6 × 2.8 mm, AEC-Q200 | Cyntec | VCMV063T-R68MN2T | ||
Q1, Q2 | 2 | 40 V, 4.6 mΩ, 7 nC, SON 5 × 6 | Infineon | IAUC60N04S6L039 |
RS | 1 | Shunt, 5 mΩ, 0508, 1 W, AEC-Q200 | Susumu |
KRL2012E-M-R005-F-T5 |
U1 | 1 | LM5149-Q1 80-V synchronous buck controller with AEF, AEC-Q100 | Texas Instruments | LM5149QRGYRQ1 |