component
UC2845BM
Public Made by Adomby adom
HGSEMI AC-DC Controllers And Regulators, SOP-8. Pinout cross-checked by two models against the datasheet, KiCad symbol/footprint/3D.
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UC2845BM
HGSEMI · AC-DC Controllers And Regulators · SOP-8
UC2845BM from HGSEMI, in a SOP-8. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | COMP | bidirectional | Error amplifier compensation terminal; pulling this pin below two diode drops shuts down the controller and forces the PWM output high until the shutdown condition is removed. |
| 2 | VFB | input | Error amplifier input (voltage-feedback node) with a recommended input voltage range of 0 to 5.0 V. |
| 3 | ISENSE | input | Current-sense comparator input whose maximum input signal is 1.0 V (typ.), so peak sense current is set as Ismax = 1.0 V / Rs; raising it above 1 V shuts down the output. |
| 4 | RT/CT | bidirectional | RC oscillator timing input with a recommended voltage range of 0 to 5.0 V and an oscillation frequency range of 100 kHz to 500 kHz. |
| 5 | GND | power_in | Power ground; the datasheet requires the bypass capacitor to be placed close to pin 5 because of high peak currents when driving capacitive loads. |
| 6 | OUTPUT | output | PWM totem-pole output for driving an N-channel MOSFET, rated for ±1 A peak output current and 200 mA average output current, and held low when off; pin 6 needs a divider to GND during undervoltage lockout to prevent leakage from turning the power switch on. |
| 7 | VCC | power_in | Supply pin with a maximum recommended supply voltage of 28 V and an absolute maximum of 30 V, with start-up current below 0.5 mA and a 34 V (typ.) Zener clamp at 25 mA. |
| 8 | VREF | power_in | Internally trimmed 5.00 V (4.95 V to 5.05 V at 25 °C) reference output, capable of sourcing up to 20 mA. |
Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | HGSEMI |
| Package | SOP-8 |
| Category | Power Management (PMIC) |
| Pins | 8 |
Electrical characteristics
Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| 电源电压 | Vcc | 30 | V | 3 | |||
| 输出电流 | Io | -1 | 1 | A | 3 | ||
| 模拟输入(2，3 脚) | VI(ANA) | -0.3 | 5.5 | V | 3 | ||
| 误差放大器输出灌电流 | ISINK(EA) | 10 | mA | 3 | |||
| 耗散功率 | PD | 850 | mW | Tamb≤25°C | 3 | ||
| 结对环境热阻 | RthJA | 143 | °C /W | 3 | |||
| 结壳（上）热阻 | RthJC | 47.6 | °C /W | 3 | |||
| 存储温度 | Tstg | -65 | 150 | °C | 3 | ||
| 闩锁 | LU | 100 | mA | 25°C & 125°C | 3 | ||
| ESD 人体模式 | ESD-HBM | -2000 | 2000 | V | 人体模式（25°C） | 3 | |
| ESD 充电器件模式 | ESD-CDM | -500 | 500 | V | 充电器件模式（25°C） | 3 | |
| 引脚温度（焊接 10s） | TLEAD | 245 | °C | 焊接 10s | 3 | ||
| 电源电压 | VCC | 28 | V | 3 | |||
| 输入电压 RT/CT、VFB、ISENSE | VI | 0 | 5 | V | 3 | ||
| 输出电压 | VO | 0 | 28 | V | 3 | ||
| 电源电流 | ICC | 25 | mA | 3 | |||
| 平均输出电流 | Io | 200 | mA | 3 | |||
| 基准输出电流 | Io(ref) | -20 | mA | 3 | |||
| 振荡频率 | fosc | 100 | 500 | kHz | 3 | ||
| 正常工作环温 | Ta | -40 | 85 | °C | 3 | ||
| 输出电压 (基准) | VREF | 4.95 | 5 | 5.05 | V | Ta = 25°C，IL =1mA | 4 |
| 线性调整率 | ∆VREF1 | 6 | 20 | mV | VCC=12V~25V | 4 | |
| 负载调整率 | ∆VREF2 | 6 | 25 | mV | IL=1 mA ~20 mA | 4 | |
| 温度稳定性 | TS | 0.2 | 0.4 | mV/°C | 4 | ||
| 总的输出变化 | ∆VREF3 | 4.82 | 5.18 | V | Line，Load，Temp | 4 | |
| 长期稳定性 | S | 5 | 25 | mV | Ta = 25°C，1000 小时 | 4 | |
| 输出短路电流 | ISC | -30 | -100 | -180 | mA | VREF=0V，Ta=25°C | 4 |
| 初始精度 | f | 49 | 52 | 55 | kHz | Ta=25°C | 4 |
| 电压稳定性 | ∆f/∆VCC | 0.2 | 1 | % | VCC=12V~25V | 4 | |
| 放电电流 | Idischg | 7.5 | 8.8 | mA | VOSC =2V | 4 | |
| 输入电压 (误差放大器) | VI(EA) | 2.42 | 2.5 | 2.58 | V | Vpin1=2.5V | 4 |
| 输入偏置电流 (误差放大器) | IBIAS | -0.1 | -2 | µA | 4 | ||
| 开环电压增益 | AVOL | 60 | 90 | dB | 2 ≤Vo≤4V | 4 | |
| 单位增益带宽 | BW | 0.7 | 1 | MHz | Ta=25°C | 4 | |
| 电源电压抑制比 (误差放大器) | PSRR | 60 | 70 | dB | 12≤Vcc≤25V | 4 | |
| 输出灌电流 | Isink | 2 | 12 | mA | Vpin 2=2.7V，Vpin 1=1.1V | 4 | |
| 输出拉电流 | Isource | -0.5 | -1 | mA | Vpin 2=2.3V，Vpin 1=5V | 4 | |
| 输出高电平 (误差放大器) | VOH | 5 | 6.2 | V | Vpin 2=2.3V，RL=15kΩ to GND | 4 | |
| 输出低电平 (误差放大器) | VOL | 0.8 | 1.1 | V | Vpin 2=2.7V，RL=15kΩ to VREF | 4 | |
| 增益 | GV | 2.85 | 3 | 3.15 | V/V | note1，2 | 4 |
| 最大输入信号 | VI(MAX) | 0.9 | 1 | 1.1 | V | Vpin 1=5V(注 1) | 4 |
| 输入偏置电流 (电流采样) | IBIAS | -2 | -10 | µA | 4 | ||
| 输出延迟 | TPLH | 150 | 300 | ns | Vpin 3=0 to 2V | 4 | |
| 输出低电平 | VOL | 0.1 | 0.4 | V | Isink=20mA | 4 | |
| 输出低电平 | VOL | 1.6 | 2.2 | V | Isink=200mA | 4 | |
| 输出高电平 | VOH | 13 | 13.5 | V | Isource=20mA | 4 | |
| 输出高电平 | VOH | 12 | 13.5 | V | Isource=200mA | 4 | |
| 上升时间 | tR | 50 | 150 | ns | Ta=25°C，CL=1nF | 4 | |
| 下降时间 | tF | 50 | 150 | ns | Ta=25°C，CL=1nF | 4 | |
| UVLO 低电平输出饱和压降 | VOL(UVLO) | 0.7 | 1.2 | V | Vcc=5V，Isink=1mA | 5 | |
| 启动阈值 | VTH(ST) | 7.8 | 8.4 | 9 | V | 5 | |
| 开启后最小工作电压 | VOPR(min) | 7 | 7.6 | 8.2 | V | 5 | |
| 最小占空比 | D(MIN) | 0 | % | 5 | |||
| 最大占空比 | D(MAX) | 47 | 48 | 50 | % | 5 | |
| 启动电流 | IST | 0.3 | 0.5 | mA | 5 | ||
| 工作电流 | ICC(opr) | 12 | 17 | mA | Vpin 2=Vpin 3=0V | 5 | |
| Vcc 齐纳电压 | Vz | 30 | 34 | V | Icc=25mA | 5 |
CAD (KiCad official)
- Symbol:
UC2845BM - Footprint:
Package_SO:SOIC-8_3.9x4.9mm_P1.27mm - 3D model: SOP-8 (KiCad packages3D, STEP)
- 3D model files:
uc2845bm-etched.step/uc2845bm-etched.glbcarry the MPN laser-etched on the die in a toggleableAdom.LaserEtchgroup (Fusion-ready);uc2845bm.step/uc2845bm.glbare the bare package body.
Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- Datasheet: HGSEMI datasheet (11 pp, sha256
bf9615dc0d4e1097, retrieved 2026-10-17, tier: lcsc) - Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- Extractor: parts-factory
2.0.0/extract_pins 0.3, primaryclaude-haiku-5-5(text), consensusclaude-sonnet-5-5(agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish. - CAD: KiCad official libraries (CC-BY-SA 4.0).
# UC2845BM
**HGSEMI** · AC-DC Controllers And Regulators · SOP-8
UC2845BM from HGSEMI, in a SOP-8. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.
## Pinout
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | COMP | bidirectional | Error amplifier compensation terminal; pulling this pin below two diode drops shuts down the controller and forces the PWM output high until the shutdown condition is removed. |
| 2 | VFB | input | Error amplifier input (voltage-feedback node) with a recommended input voltage range of 0 to 5.0 V. |
| 3 | ISENSE | input | Current-sense comparator input whose maximum input signal is 1.0 V (typ.), so peak sense current is set as Ismax = 1.0 V / Rs; raising it above 1 V shuts down the output. |
| 4 | RT/CT | bidirectional | RC oscillator timing input with a recommended voltage range of 0 to 5.0 V and an oscillation frequency range of 100 kHz to 500 kHz. |
| 5 | GND | power_in | Power ground; the datasheet requires the bypass capacitor to be placed close to pin 5 because of high peak currents when driving capacitive loads. |
| 6 | OUTPUT | output | PWM totem-pole output for driving an N-channel MOSFET, rated for ±1 A peak output current and 200 mA average output current, and held low when off; pin 6 needs a divider to GND during undervoltage lockout to prevent leakage from turning the power switch on. |
| 7 | VCC | power_in | Supply pin with a maximum recommended supply voltage of 28 V and an absolute maximum of 30 V, with start-up current below 0.5 mA and a 34 V (typ.) Zener clamp at 25 mA. |
| 8 | VREF | power_in | Internally trimmed 5.00 V (4.95 V to 5.05 V at 25 °C) reference output, capable of sourcing up to 20 mA. |
## Key specifications
| Parameter | Value |
|---|---|
| Manufacturer | HGSEMI |
| Package | SOP-8 |
| Category | Power Management (PMIC) |
| Pins | 8 |
## Electrical characteristics
Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).
| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| 电源电压 | Vcc | | | 30 | V | | 3 |
| 输出电流 | Io | -1 | | 1 | A | | 3 |
| 模拟输入(2，3 脚) | VI(ANA) | -0.3 | | 5.5 | V | | 3 |
| 误差放大器输出灌电流 | ISINK(EA) | | | 10 | mA | | 3 |
| 耗散功率 | PD | | | 850 | mW | Tamb≤25°C | 3 |
| 结对环境热阻 | RthJA | | | 143 | °C /W | | 3 |
| 结壳（上）热阻 | RthJC | | | 47.6 | °C /W | | 3 |
| 存储温度 | Tstg | -65 | | 150 | °C | | 3 |
| 闩锁 | LU | | | 100 | mA | 25°C & 125°C | 3 |
| ESD 人体模式 | ESD-HBM | -2000 | | 2000 | V | 人体模式（25°C） | 3 |
| ESD 充电器件模式 | ESD-CDM | -500 | | 500 | V | 充电器件模式（25°C） | 3 |
| 引脚温度（焊接 10s） | TLEAD | | | 245 | °C | 焊接 10s | 3 |
| 电源电压 | VCC | | | 28 | V | | 3 |
| 输入电压 RT/CT、VFB、ISENSE | VI | 0 | | 5 | V | | 3 |
| 输出电压 | VO | 0 | | 28 | V | | 3 |
| 电源电流 | ICC | | | 25 | mA | | 3 |
| 平均输出电流 | Io | | | 200 | mA | | 3 |
| 基准输出电流 | Io(ref) | | | -20 | mA | | 3 |
| 振荡频率 | fosc | | 100 | 500 | kHz | | 3 |
| 正常工作环温 | Ta | -40 | | 85 | °C | | 3 |
| 输出电压 (基准) | VREF | 4.95 | 5 | 5.05 | V | Ta = 25°C，IL =1mA | 4 |
| 线性调整率 | ∆VREF1 | | 6 | 20 | mV | VCC=12V~25V | 4 |
| 负载调整率 | ∆VREF2 | | 6 | 25 | mV | IL=1 mA ~20 mA | 4 |
| 温度稳定性 | TS | | 0.2 | 0.4 | mV/°C | | 4 |
| 总的输出变化 | ∆VREF3 | 4.82 | | 5.18 | V | Line，Load，Temp | 4 |
| 长期稳定性 | S | | 5 | 25 | mV | Ta = 25°C，1000 小时 | 4 |
| 输出短路电流 | ISC | -30 | -100 | -180 | mA | VREF=0V，Ta=25°C | 4 |
| 初始精度 | f | 49 | 52 | 55 | kHz | Ta=25°C | 4 |
| 电压稳定性 | ∆f/∆VCC | | 0.2 | 1 | % | VCC=12V~25V | 4 |
| 放电电流 | Idischg | 7.5 | | 8.8 | mA | VOSC =2V | 4 |
| 输入电压 (误差放大器) | VI(EA) | 2.42 | 2.5 | 2.58 | V | Vpin1=2.5V | 4 |
| 输入偏置电流 (误差放大器) | IBIAS | | -0.1 | -2 | µA | | 4 |
| 开环电压增益 | AVOL | 60 | 90 | | dB | 2 ≤Vo≤4V | 4 |
| 单位增益带宽 | BW | 0.7 | 1 | | MHz | Ta=25°C | 4 |
| 电源电压抑制比 (误差放大器) | PSRR | 60 | 70 | | dB | 12≤Vcc≤25V | 4 |
| 输出灌电流 | Isink | 2 | 12 | | mA | Vpin 2=2.7V，Vpin 1=1.1V | 4 |
| 输出拉电流 | Isource | -0.5 | -1 | | mA | Vpin 2=2.3V，Vpin 1=5V | 4 |
| 输出高电平 (误差放大器) | VOH | 5 | 6.2 | | V | Vpin 2=2.3V，RL=15kΩ to GND | 4 |
| 输出低电平 (误差放大器) | VOL | | 0.8 | 1.1 | V | Vpin 2=2.7V，RL=15kΩ to VREF | 4 |
| 增益 | GV | 2.85 | 3 | 3.15 | V/V | note1，2 | 4 |
| 最大输入信号 | VI(MAX) | 0.9 | 1 | 1.1 | V | Vpin 1=5V(注 1) | 4 |
| 输入偏置电流 (电流采样) | IBIAS | | -2 | -10 | µA | | 4 |
| 输出延迟 | TPLH | | 150 | 300 | ns | Vpin 3=0 to 2V | 4 |
| 输出低电平 | VOL | | 0.1 | 0.4 | V | Isink=20mA | 4 |
| 输出低电平 | VOL | | 1.6 | 2.2 | V | Isink=200mA | 4 |
| 输出高电平 | VOH | 13 | 13.5 | | V | Isource=20mA | 4 |
| 输出高电平 | VOH | 12 | 13.5 | | V | Isource=200mA | 4 |
| 上升时间 | tR | | 50 | 150 | ns | Ta=25°C，CL=1nF | 4 |
| 下降时间 | tF | | 50 | 150 | ns | Ta=25°C，CL=1nF | 4 |
| UVLO 低电平输出饱和压降 | VOL(UVLO) | | 0.7 | 1.2 | V | Vcc=5V，Isink=1mA | 5 |
| 启动阈值 | VTH(ST) | 7.8 | 8.4 | 9 | V | | 5 |
| 开启后最小工作电压 | VOPR(min) | 7 | 7.6 | 8.2 | V | | 5 |
| 最小占空比 | D(MIN) | | | 0 | % | | 5 |
| 最大占空比 | D(MAX) | 47 | 48 | 50 | % | | 5 |
| 启动电流 | IST | | 0.3 | 0.5 | mA | | 5 |
| 工作电流 | ICC(opr) | | 12 | 17 | mA | Vpin 2=Vpin 3=0V | 5 |
| Vcc 齐纳电压 | Vz | 30 | 34 | | V | Icc=25mA | 5 |
## CAD (KiCad official)
- Symbol: `UC2845BM`
- Footprint: `Package_SO:SOIC-8_3.9x4.9mm_P1.27mm`
- 3D model: SOP-8 (KiCad packages3D, STEP)
- 3D model files: `uc2845bm-etched.step` / `uc2845bm-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `uc2845bm.step` / `uc2845bm.glb` are the bare package body.
## Provenance
Data extracted from the manufacturer datasheet, not a distributor listing:
- **Datasheet:** [HGSEMI datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8602944239701536768) (11 pp, sha256 `bf9615dc0d4e1097`, retrieved 2026-10-17, tier: lcsc)
- **Datasheet language:** Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-haiku-5-5` (text), consensus `claude-sonnet-5-5` (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
- **CAD:** KiCad official libraries (CC-BY-SA 4.0).
[Datasheet PDF](docs/uc2845bm-datasheet.pdf)