LM5166は小型で使いやすい、3V~65Vで超低IQの同期整流降圧コンバータで、広い範囲の入力電圧と負荷電流にわたって高い効率を維持します。ハイサイドとローサイドのパワーMOSFETが搭載されており、3.3Vまたは5Vの固定出力電圧、または可変出力電圧で、最大500mAの出力電流を供給できます。このコンバータは、実装を簡素化し、同時に対象アプリケーションに合わせて性能を最適化できるよう設計されています。軽負荷時の効率を最適化するにはパルス周波数変調(PFM)モードを、ほぼ一定の周波数で動作するためにはコンスタント・オン・タイム(COT)制御方式を使用できます。いずれの制御方式にもループ補償は必要なく、非常に優れたラインおよび負荷過渡応答と、大きな降圧変換率について短いPWMオン時間を実現します。
ハイサイドのPチャネルMOSFETは100%デューティ・サイクルで動作可能なため、最低のドロップアウト電圧を実現し、ゲート駆動用のブートストラップ・コンデンサが必要ありません。また、電流制限の設定ポイントを変更可能で、特定の負荷電流の要件に応じてインダクタの選択を最適化できます。スタートアップ時間の選択や変更には、最小遅延(ソフトスタートなし)、内部的に固定(900μs)、コンデンサを使用して外部でソフトスタートをプログラムのオプションを選択できます。オープン・ドレインのPGOODインジケータは、シーケンシング、フォルト報告、出力電圧監視に使用できます。LM5166は0.5mmピン・ピッチの10ピンVSONパッケージで供給されます。
Changes from A Revision (December 2016) to B Revision
Changes from * Revision (December 2016) to A Revision
PIN | I/O(1) | DESCRIPTION | |
---|---|---|---|
NO. | NAME | ||
1 | SW | P | Switching node that is internally connected to the drain of the PFET buck switch (high side) and the drain of the NFET synchronous rectifier (low side). Connect to the buck inductor. |
2 | VIN | P | Regulator supply input pin to high-side power MOSFET and internal bias rail LDO. Connect to input supply and input filter capacitor CIN. The path from the VIN pin to the input capacitor must be as short as possible. |
3 | ILIM | I | Programming pin for current limit. Connecting the appropriate resistance from the ILIM pin to GND selects one of the three current limit options. The available current limit options are detailed in Table 3. |
4 | SS | I | Programming pin for the soft-start delay. If a 100-kΩ resistor is connected from the SS pin to GND, the internal soft-start circuit is disabled and the FB comparator reference steps immediately from zero to full value when the regulator is enabled by the EN input. If the SS pin is left open, the internal soft-start circuit ramps the FB reference from zero to full value in 900 µs. If a capacitor is connected from the SS pin to GND, the soft-start time can be set longer than 900 µs. |
5 | RT | I | Mode select and on-time programming pin for Constant On-Time control. Connect a resistor from the RT pin to GND to program the on-time and hence switching frequency. Short RT to GND to select PFM (pulse frequency modulation) operation. |
6 | PGOOD | O | Power Good output flag pin. PGOOD is connected to the drain of an NFET that holds the pin low when either FB or VOUT is not in regulation. Use a 10-kΩ to 100-kΩ pullup resistor to system voltage rail or VOUT (no higher than 12 V). |
7 | EN | I | Input pin of the precision enable / UVLO comparator. The regulator is enabled when the EN pin voltage is greater than 1.22 V. |
8 | VOUT or FB | I | Feedback input to the voltage regulation loop for the LM5166 Adjustable Output version, or a VOUT pin connects the internal feedback resistor divider to the regulator output voltage for the fixed 3.3-V or 5-V options. The FB pin connects the internal feedback comparator to an external resistor divider for the adjustable voltage option, and the reference for the FB pin comparator is 1.223 V. |
9 | HYS | O | Drain of internal NFET that is turned off when the EN input is greater than the EN pin threshold. External resistors from HYS to EN and GND program the input UVLO threshold and hysteresis. |
10 | GND | G | Regulator ground return. |
— | PAD | P | Connect to GND pin and system ground on PCB. Path to CIN must be as short as possible. |
MIN | MAX | UNIT | ||
---|---|---|---|---|
VIN, EN to GND | –0.3 | 68 | V | |
SW to GND | –0.7 | VVIN + 0.3 | V | |
20-ns transient | –3 | |||
PGOOD, VOUT(3) to GND | –0.3 | 16 | V | |
HYS to GND | –0.3 | 7 | V | |
ILIM, SS, RT, FB(4) to GND | –0.3 | 3.6 | V | |
Maximum junction temperature, TJ | –40 | 150 | °C | |
Storage temperature, Tstg | –55 | 150 | °C |
VALUE | UNIT | |||
---|---|---|---|---|
V(ESD) | Electrostatic discharge | Human body model (HBM), per ANSI/ESDA/JEDEC JS-001(1) | ±2000 | V |
Charged device model (CDM), per JEDEC specification JESD22-C101(2) | ±1000 |
MIN | NOM | MAX | UNIT | ||
---|---|---|---|---|---|
Input voltages | VIN | 3 | 65 | V | |
EN | –0.3 | 65 | |||
PGOOD | –0.3 | 12 | |||
HYS | –0.3 | 5.5 | |||
Output current | IOUT | 0 | 500 | mA | |
Temperature | Operating junction temperature | –40 | 150 | °C |
THERMAL METRIC(1) | LM5166 | UNIT | |
---|---|---|---|
DRC (VSON) | |||
10 PINS | |||
RθJA | Junction-to-ambient thermal resistance | 49.1 | °C/W |
RθJC(top) | Junction-to-case (top) thermal resistance | 57.2 | °C/W |
RθJB | Junction-to-board thermal resistance | 26.6 | °C/W |
ψJT | Junction-to-top characterization parameter | 0.8 | °C/W |
ψJB | Junction-to-board characterization parameter | 23.8 | °C/W |
RθJC(bot) | Junction-to-case (bottom) thermal resistance | 4.8 | °C/W |
PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT | |
---|---|---|---|---|---|---|
IQ-SD | VIN DC supply current, shutdown | VEN = 0 V, TJ = 25°C | 4 | 6 | µA | |
IQ-SLEEP | VIN DC supply current, no load | VFB = 1.5 V, TJ = 25°C | 9.7 | 15 | µA | |
IQ-SLEEP-VINMAX | VIN DC supply current, no load | VFB = 1.5 V, VVIN = 65 V, TJ = 25°C | 10 | 15 | µA | |
IQ-ACTIVE-PFM | VIN DC supply current, active | PFM mode, RRT = 0 Ω, RSS = 100 kΩ | 205 | µA | ||
IQ-ACTIVE-COT | VIN DC supply current, active | COT mode, RRT = RSS = 100 kΩ | 320 | µA | ||
POWER SWITCHES | ||||||
RDSON1 | High-side MOSFET RDS(on) | ISW = –100 mA | 0.93 | Ω | ||
RDSON2 | Low-side MOSFET RDS(on) | ISW = 100 mA | 0.48 | Ω | ||
CURRENT LIMITING | ||||||
IHS_LIM1 | High-side peak current limit threshold | See Table 3 | 1125 | 1250 | 1375 | mA |
IHS_LIM2 | 675 | 750 | 825 | |||
IHS_LIM3 | 440 | 500 | 560 | |||
ILS_LIM1 | Low-side valley current limit threshold | See Table 3 | 415 | mA | ||
ILS_LIM2 | 315 | |||||
REGULATION COMPARATOR | ||||||
VVOUT5 | VOUT 5-V DC setpoint | LM5166X | 4.9 | 5.0 | 5.1 | V |
VVOUT3.3 | VOUT 3.3-V DC setpoint | LM5166Y | 3.23 | 3.3 | 3.37 | V |
IVOUT | VOUT pin input current | VVOUT = 5 V, LM5166X | 7 | µA | ||
VVOUT = 3.3 V, LM5166Y | 3.8 | |||||
VFB1 | Lower FB regulation threshold (PFM and COT) |
Adjustable VOUT version | 1.208 | 1.223 | 1.238 | V |
VFB2 | Upper FB regulation threshold (PFM) | 1.218 | 1.233 | 1.248 | V | |
IFB | FB pin input bias current | VFB = 1 V | 25 | nA | ||
FBHYS-PFM | FB comparator PFM hysteresis | PFM mode | 10 | mV | ||
FBHYS-COT | FB comparator dropout hysteresis | COT mode | 4 | mV | ||
FBLINE-REG | FB threshold variation over line | VVIN = 3 V to 65 V | 0.005 | %/V | ||
VOUTLINE-REG | VOUT threshold variation over line | LM5166X, VVIN = 6 V to 65 V LM5166Y, VVIN = 4.5 V to 65 V |
0.005 | %/V | ||
POWER GOOD | ||||||
UVTRISING | PGOOD comparator | VFB rising relative to VFB1 threshold | 94% | |||
UVTFALLING | VFB falling relative to VFB1 threshold | 87% | ||||
RPGOOD | PGOOD on-resistance | VFB = 1 V | 80 | 200 | Ω | |
VINMIN-PGOOD | Minimum required VIN for valid PGOOD | VVIN falling IPGOOD = 0.1 mA, VPGOOD < 0.5 V |
1.2 | 1.65 | V | |
IPGOOD | PGOOD off-state leakage | VFB = 1.2 V, VPGOOD = 5.5 V | 10 | 100 | nA | |
ENABLE / UVLO | ||||||
VIN-ON | Turnon threshold | VVIN rising | 2.60 | 2.75 | 2.95 | V |
VIN-OFF | Turnoff threshold | VVIN falling | 2.35 | 2.45 | 2.60 | V |
VEN-ON | EN turnon threshold | VEN rising | 1.163 | 1.22 | 1.276 | V |
VEN-OFF | EN turnoff threshold | VEN falling | 1.109 | 1.144 | 1.178 | V |
VEN-HYS | EN hysteresis | 76 | mV | |||
VEN-SD | EN shutdown threshold | VEN falling | 0.3 | 0.6 | V | |
RHYS | HYS on-resistance | VEN = 1 V | 80 | 200 | Ω | |
IHYS | HYS off-state leakage | VEN = 1.5 V, VHYS = 5.5 V | 10 | 100 | nA | |
SOFT-START | ||||||
ISS | Soft-start charging current | VSS = 1 V | 10 | µA | ||
TSS-INT | Soft-start rise time | SS floating | 900 | µs | ||
THERMAL SHUTDOWN | ||||||
TJ-SD | Thermal shutdown threshold | 170 | °C | |||
TJ-SD-HYS | Thermal shutdown hysteresis | 10 | °C |
PARAMETER | TEST CONDITIONS | MIN | TYP | MAX | UNIT | |
---|---|---|---|---|---|---|
TON-MIN | Minimum on-time | 180 | ns | |||
TON1 | On-time | 16 kΩ from RT to GND | 280 | ns | ||
TON2 | On-time | 75 kΩ from RT to GND | 1150 | ns |
See schematic, Figure 52 |
LF = 150 µH COUT = 47 µF |
FSW(nom) = 100 kHz RRT = 309 kΩ |
See schematic, Figure 70 |
LF = 4.7 µH COUT = 47 µF |
FSW(nom) = 600 kHz RRT = 0 Ω |
RRT = 100 kΩ |
VVIN = 65 V |
Time Scale: 20 ms/Div CH1: VSW, 5 V/Div |
CH2: VOUT, 50 mV/Div CH4: IL, 200 mA/Div |
Time Scale: 2 ms/Div CH1: VIN, 2 V/Div |
CH2: VOUT, 1 V/Div CH4: IL, 200 mA/Div |
Time Scale: 20 ms/Div CH1: VSW, 5 V/Div |
CH2: VOUT, 50 mV/Div CH4: IL, 400 mA/Div |
Time Scale: 2 ms/Div CH1: VIN, 2 V/Div |
CH2: VOUT, 1 V/Div CH4: IL, 400 mA/Div |
Time Scale: 50 ms/Div CH1: VSW, 5 V/Div |
CH2: VOUT, 50 mV/Div CH4: IL, 400 mA/Div |
See schematic, Figure 63 |
LF = 47 µH COUT = 47 µF |
FSW(nom) = 200 kHz RRT = 100 kΩ |
See schematic, Figure 77 |
LF = 22 µH COUT = 200 µF |
FSW(nom) = 100 kHz RRT = 0 Ω |
RRT = 100 kΩ |
LM5166X |
Time Scale: 10 µs/Div CH1: VSW, 5 V/Div |
CH2: VOUT, 50 mV/Div CH4: IL, 200 mA/Div |
Time Scale: 100 µs/Div CH1: VSW, 4 V/Div |
CH4: IL, 200 mA/Div |
Time Scale: 10 µs/Div CH1: VSW, 5 V/Div |
CH2: VOUT, 100 mV/Div CH4: IL, 400 mA/Div |
Time Scale: 20 µs/Div CH1: VSW, 4 V/Div |
CH4: IL, 400 mA/Div |
Time Scale: 20 µs/Div CH1: VSW, 5 V/Div |
CH2: VOUT, 100 mV/Div CH4: IL, 400 mA/Div |