ZHCSLO5B December 2020 – December 2021 LM25149
PRODUCTION DATA
Table 9-7 shows the intended input, output, and performance parameters for this design example.
DESIGN PARAMETER | VALUE |
---|---|
Input voltage range (steady-state) | 8 V to 36 V |
Min transient input voltage | 4 V |
Max transient input voltage | 40 V |
Output voltage | 3.3 V |
Output current | 20 A |
Switching frequency | 400 kHz |
Output voltage regulation | ±1% |
Standby current, no-load | 44 µA |
Shutdown current | 4.6 µA |
Soft-start time | 3 ms |
The switching frequency is set at 400 kHz by resistors RRT1 and RRT2. The selected buck regulator 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 9.1.1.4.
REFERENCE DESIGNATOR | QTY | SPECIFICATION | MANUFACTURER | PART NUMBER |
---|---|---|---|---|
CIN | 4 | 10 µF, 50 V, X7R, 1210, ceramic | AVX | 12105C106K4Z2A |
TDK | C3225X7R1H106K250AC | |||
Murata | GRM32ER71H106KA12L | |||
CO | 8 | 47 µF, 6.3 V, X7R, 1210, ceramic | Murata | GCM32ER70J476KE19L |
47 µF, 10 V, X7S, 1210, ceramic | TDK | CGA6P1X7S1A476M250AC | ||
4 | 100 µF, 6.3 V, X7S, 1210, ceramic | Murata | GRT32EC70J107ME13 | |
LO1, LO2 | 2 | 2.2 μH, 4.5 mΩ, 32 A, 11.3 × 10 × 6 mm | Coilcraft | XKL1060-222MEC |
2.2 μH, 4.3 mΩ, 12.5 A, 6.7 × 6.5 × 6.1 mm | Coilcraft | XGL6060-222MEC | ||
2.2 µH, 6.5 mΩ, 10 A, 10 × 11 × 3.8 mm | Würth Electronik | 74437368022 | ||
Q1, Q3 | 2 | 40 V, 4.7 mΩ, 12 nC, SON 5 × 6 | Texas Instruments | CSD18503Q5A |
Q2, Q4 | 2 | 40 V, 2.7 mΩ, 35 nC, SON 5 × 6 | Texas Instruments | CSD18511Q5A |
RS1, RS2 | 2 | Shunt, 4 mΩ, 0508, 1 W | Susumu |
KRL2012E-M-R004-F-T5 |
U1, U2 | 2 | LM25149 42-V synchronous buck controller with AEF | Texas Instruments | LM25149RGYR |
LM25148 42-V synchronous buck controller | Texas Instruments | LM25148RGYR |