ZHCSL47A April 2020 – January 2021 LM5181
PRODUCTION DATA
The required input, output, and performance parameters for this application example are shown in Table 9-1.
| DESIGN PARAMETER | VALUE |
|---|---|
| Input voltage range | 10 V to 65 V |
| Input UVLO thresholds | 9.5 V on, 6.5 V off |
| Output voltage | 5 V |
| Rated load current, VIN = 24 V | 0.5 A |
| Output voltage regulation | ±1.5% |
| Output voltage ripple | < 100 mV |
The target full-load efficiency is 87.5% based on a nominal input voltage of 24 V and an isolated output voltage of 5 V. The LM5181 is chosen to deliver a fixed 5-V output voltage set by resistor RFB connected between the SW and FB pins. The input voltage turnon and turnoff thresholds are established by RUV1 and RUV2. The required components are listed in Table 9-2. Transformers for other designs are listed in Table 9-3.
| REF DES | QTY | SPECIFICATION | VENDOR | PART NUMBER |
|---|---|---|---|---|
| CIN | 1 | 2.2 μF, 100 V, X7R, 1206, ceramic | AVX | 12061C225KAT4A |
| 2.2 μF, 100 V, X7R, 1210, ceramic | TDK | C3225X7R2A225K230AB | ||
| Murata | GCJ32DR72A225KA01L | |||
| Taiyo Yuden | HMK325B7225KN-T | |||
| COUT | 1 | 47 μF, 10 V, X7S, 1210, ceramic | TDK | C3225X7S1A476M250AC |
| 47 μF, 10 V, X7R, 1210, ceramic | Murata | GRM32ER71A476KE15L | ||
| Taiyo Yuden | LMK325B7476MM-TR | |||
| CSS | 1 | 47 nF, 16 V, X7R, 0402 | Std | Std |
| DCLAMP | 1 | Zener, 24 V, 1 W, PowerDI-123 | DFLZ24-7 | Diodes Inc. |
| DF | 1 | Switching diode, 75 V, 0.25 A, SOD-323 | CMDD4448 | Central Semi |
| DFLY | 1 | Schottky diode, 40 V, 2 A, SOD-123 | FSV340FP | Onsemi |
| DOUT | 1 | Zener, 5.6 V, 5%, SOD-523 | BZX585-C5V6 | Nexperia |
| RFB | 1 | 158 kΩ, 1%, 0402 | Std | Std |
| RSET | 1 | 12.1 kΩ, 1%, 0402 | Std | Std |
| RTC | 1 | 130 kΩ, 1%, 0402 | Std | Std |
| RUV1 | 1 | 536 kΩ, 1%, 0603 | Std | Std |
| RUV2 | 1 | 100 kΩ, 1%, 0402 | Std | Std |
| T1 | 1 | 44 μH, 1.4 A, 3 : 1, 8.2 × 8.6 × 9.6 mm | Würth Electronik | 750318633 |
| U1 | 1 | LM5181 PSR flyback converter, VSON-8 | Texas Instruments | LM5181NGUR |
| OUTPUT VOLTAGE (RANGE) | TURNS RATIO | LMAG, ISAT | DIMENSIONS | VENDOR | PART NUMBER |
|---|---|---|---|---|---|
| 3.3 V (up to 4 V) | 4 : 1 | 40 μH, 1 A | 8.6 × 8.26 × 9.65 mm | Würth Electronik | 750319117 |
| 5 V (4 V to 5.5 V) | 3 : 1 | 44 μH, 1 A | 750318633 | ||
| 12 V (5.5 V to 16 V) | 1 : 1 | 750318737 | |||
| 24 V (16 V to 32 V) | 1 : 2 | 750318738 | |||
| 48 V (32 V to 50 V) | 1 : 3 | 750319118 | |||
| 15 V and –7.5 V dual | 1 : 1.5 : 0.8 | 30 μH, 1 A | 750319119 |