JAJSL65 February 2023 LM5148-Q1
PRODUCTION DATA
Table 9-8 shows the intended input, output, and performance parameters for this automotive design example. Refer to 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 | 9.9 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 Table 9-9, and many of the components are available from multiple vendors. The MOSFETs in particular are chosen for lowest total conduction and switching power loss.. This design uses a low-DCR composite inductor, and ceramic output capacitors.
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 | 0.56 μH, 3.6 mΩ, 13 A, 6.6 × 6.6 × 4.8 mm, AEC-Q200 | Würth Electronik | 744373490056 |
0.68 µH, 2.9 mΩ, 22 A, 6.7 × 6.5 × 3.1 mm, AEC-Q200 | Colicraft | XGL6030-681 | ||
Q1, Q2 | 2 | 40 V, 4.6 mΩ, 7 nC, SON 5 × 6, AEC-Q101 | Infineon | IAUC60N04S6L039 |
RS | 1 | Shunt, 5 mΩ, 0508, 1 W, AEC-Q200 | Susumu | KRL2012E-M-R005-F-T5 |
U1 | 1 | LM5148-Q1 80-V synchronous buck controller, AEC-Q100 | Texas Instruments | LM5148QRGYRQ1 |