ZHCSGB0B November 2017 – November 2020 LM5145
PRODUCTION DATA
The design procedure for an LM5145-based regulator for a given application is streamlined by using the LM5145 Quickstart Calculator available as a free download, or by availing of TI's WEBENCH? Power Designer. Such tools are complemented by the availability of an LM5145 evaluation module (EVM) design, numerous PSPICE models, as well as several LM5145 reference designs populated in the TI Designs reference design library.
The selected buck converter powertrain components are cited in Table 9-6, 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 Section 9.1.2.4.
The current limit setpoint in this design is set at 25 A based on the resistor RILIM and the 4-mΩ RDS(on) of the low-side MOSFET (typical at TJ = 25°C and VGS = 7.5 V). This design uses a low-DCR, metal-powder inductor, and composite ceramic–polymer electrolytic output capacitor implementation.
| REFERENCE DESIGNATOR | QTY | SPECIFICATION | MANUFACTURER | PART NUMBER |
|---|---|---|---|---|
| CIN | 7 | 2.2 μF, 100 V, X7R, 1210, ceramic | TDK | C3225X7R2A225M230AB |
| Murata | GRM32ER72A225KA35L | |||
| Kemet | C1210C225K1RACTU | |||
| COUT | 7 | 47 μF, 10 V, X7R, 1210, ceramic | Murata | GRM32ER71A476KE15L |
| Taiyo Yuden | LMK325B7476MM-TR | |||
| AVX | 1210ZC476KAT2A | |||
| Kemet | C1210C476M8RAC7800 | |||
| COUT(BULK) | 1 | 220 μF, 6.3 V, 10 mΩ, polymer electrolytic | Murata | ECASD60J227M010K00 |
| LF | 1 | 3.3 μH, 3.75 mΩ, 40 A, 13.45 × 12.6 × 6.3 mm | Cyntec | CMLS136E-3R3MS |
| 3.3 μH, 5.7 mΩ, 32 A, 12.5 × 12.5 × 6.2 mm | Würth Electronik | 744373965033 | ||
| Q1 | 1 | 80 V, 12 mΩ, high-side MOSFET, SON 5 × 6 | Infineon | BSC117N08NS5 |
| Q2 | 1 | 80 V, 4 mΩ, low-side MOSFET, SON 5 × 6 | Infineon | BSC037N08NS5 |
| U1 | 1 | Wide VIN synchronous buck controller | Texas Instruments | LM5145RGYR |