# UC3846L-D16-T

**UTC(Unisonic Tech)** · AC-DC Controllers & Regulators · DIP-16

UC3846L-D16-T from UTC(Unisonic Tech), in a DIP-16. 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 | C/S SS | input | Current-limit adjust / soft-start pin, with a 50 mA maximum soft start sink current. |
| 2 | VREF | power_out | Internal reference voltage output of 5.0 V min, 5.1 V typ, 5.2 V max at IO=1 mA, with 30 mA maximum reference output current. |
| 3 | C/S- | input | Current-sense amplifier input (listed as forward input of current limiting), with an analog input range of -0.3 V to +VIN. |
| 4 | C/S+ | input | Current-sense amplifier input (listed as backward input of current limiting), with an analog input range of -0.3 V to +VIN. |
| 5 | E/A+ | input | Forward (non-inverting) input of the error amplifier, with an analog input range of -0.3 V to +VIN and common mode range of 0 to VIN-2 V. |
| 6 | E/A- | input | Backward (inverting) input of the error amplifier, with an analog input range of -0.3 V to +VIN and common mode range of 0 to VIN-2 V. |
| 7 | COMP | output | Output of the error amplifier, with 5 mA maximum output current. |
| 8 | CT | passive | External timing capacitor connection that sets the oscillator frequency. |
| 9 | RT | passive | External timing resistor connection that sets the oscillator frequency, with 5 mA maximum oscillator charging current. |
| 10 | SYNC | bidirectional | Oscillator synchronization pin, with 5 mA maximum sync output current. |
| 11 | A OUT | output | Dual totem-pole output A, rated for 500 mA source or sink current. |
| 12 | GND | power_in | Ground. |
| 13 | VC | power_in | Collector supply for the output stage, with a 40 V maximum rating. |
| 14 | B OUT | output | Dual totem-pole output B, rated for 500 mA source or sink current. |
| 15 | VIN | power_in | DC supply input, with a 40 V maximum rating and under-voltage lockout start-up threshold of 8.0 V max. |
| 16 | SHUTDOWN | input | Shutdown controller input with a 350 mV typical threshold and input range of 0 to VIN. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | UTC(Unisonic Tech) |
| Package | DIP-16 |
| Category | Power Supply Chip |
| Pins | 16 |

## Electrical characteristics

Limits as printed in the datasheet (page.json `metadata.characteristics` carries them as data).

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Output Voltage | VREF | 5 | 5.1 | 5.2 | V | TJ=25°C, IO=1mA | 4 |
| Line Regulation | ΔV1 |  | 5 | 20 | mV | VIN=8V~40V | 4 |
| Load Regulation | ΔV2 |  | 3 | 15 | mV | IL=1mA~10mA | 4 |
| Total Output Variation | VREF-O | 4.95 |  | 5.25 | V | Line, Load, and Temperature (Note 2) | 4 |
| Short Circuit Output Current | IS |  | -10 | -45 | mA | VREF=0V | 4 |
| Oscillator Initial Accuracy | FOSC | 39 | 43 | 47 | kHz | TJ=25°C | 4 |
| Oscillator Voltage Stability | ΔV |  | -1 | 2 | % | VIN=8V~40V | 4 |
| Sync Output High Level | VOH(SYNC) | 3.9 | 4.35 |  | V |  | 4 |
| Sync Output Low Level | VOL(SYNC) |  | 2.3 | 2.5 | V |  | 4 |
| Sync Input High Level | VIH(SYNC) | 3.9 |  |  | V | Pin 8=0V | 4 |
| Sync Input Low Level | VIL(SYNC) |  |  | 2.5 | V | Pin 8=0V | 4 |
| Sync Input Current | ISYNC |  | 1.3 | 1.5 | mA | Sync Voltage=3.9V, Pin 8=0V | 4 |
| Error Amp Input Offset Voltage | VIO |  | 0.5 | 10 | mV |  | 4 |
| Error Amp Input Bias Current | IBIAS |  | -0.6 | -2 | µA |  | 4 |
| Error Amp Input Offset Current | IIO |  | 40 | 250 | nA |  | 4 |
| Error Amp Common Mode Range | VCM | 0 |  |  | V | VIN=8V~40V; max printed VIN-2V | 4 |
| Error Amp Open Loop Voltage Gain | GVO | 80 | 105 |  | dB | ∆VO=1.2~3V, VCM=2V | 4 |
| Error Amp CMRR | CMRRA | 75 | 100 |  | dB | VCM=0V~38V, VIN=40V | 4 |
| Error Amp PSRR | PSRRA | 80 | 105 |  | dB | VIN=8V~40V | 4 |
| Error Amp Output Sink Current | ISINK | 2 | 6 |  | mA | VID=-15mV~-5V, VPIN 7=1.2V | 4 |
| Error Amp Output Source Current | ISOURCE | -0.2 | -0.5 |  | mA | VID=15mV~5V, VPIN 7=2.5V | 4 |
| Error Amp High Level Output Voltage | VOH | 4.3 | 4.6 |  | V | RL=(Pin 7) 15kΩ | 4 |
| Error Amp Low Level Output Voltage | VOL |  | 0.7 | 1 | V |  | 4 |
| Current Sense Amplifier Gain | GA | 2.5 | 2.75 | 3 | V | VPIN 3=0V, Pin 1 Open (Note 3, 4) | 5 |
| Maximum Differential Input Signal | VIN(MAX) | 1.1 | 1.2 |  | V | Pin 1 Open (Note 3), RL (Pin 7)=15kW | 5 |
| Current Sense Input Offset Voltage | VIO |  | 5 | 25 | mV | VPIN 1=0.5V, Pin 7 Open (Note 3) | 5 |
| Current Sense CMRR | CMRRA | 60 | 83 |  | dB | VCM=1V~12V | 5 |
| Current Sense PSRR | PSRRA | 60 | 84 |  | dB | VIN=8V~40V | 5 |
| Current Sense Input Bias Current | IBIAS |  | -2.5 | -10 | µA | VPIN 1=0.5V, Pin 7 Open (Note 3) | 5 |
| Current Sense Input Offset Current | IIO |  | 0.08 | 1 | µA | VPIN 1=0.5V, Pin 7 Open (Note 3) | 5 |
| Delay to Outputs | tD |  | 200 | 500 | ns | TJ=25°C, (Note 2) | 5 |
| Current Limit Offset | VL | 0.45 | 0.5 | 0.55 | V | VPIN 3=0V, VPIN 4=0V, Pin 7 Open (Note 3) | 5 |
| Current Limit Input Bias Current | IB |  | -10 | -30 | µA | VPIN 5=VREF,VPIN 6=0V | 5 |
| Shutdown Threshold Voltage | VTH | 250 | 350 | 550 | mV |  | 5 |
| Shutdown Delay to Outputs | tD-SHUT |  | 300 | 600 | ns | TJ=25°C (Note 2) | 5 |
| Collector Leakage Current | IL |  |  | 200 | µA | VC=40V (Note 5) | 5 |
| Output Low Level | VOL1 |  | 0.1 | 0.4 | V | ISINK=20mA | 5 |
| Output Low Level | VOL2 |  | 0.4 | 2.1 | V | ISINK=100mA | 5 |
| Output High Level | VOH1 | 13 | 13.5 |  | V | ISOURCE=20mA | 5 |
| Output High Level | VOH2 | 12 | 13.2 |  | V | ISOURCE=100mA | 5 |
| Rise Time | tR |  | 50 | 300 | ns | CL=1nF, TJ=25°C (Note 2) | 5 |
| Fall Time | tF |  | 50 | 300 | ns | CL=1nF, TJ=25°C (Note 2) | 5 |
| Start-Up Threshold | VSTART |  | 7.7 | 8 | V |  | 5 |
| Supply Current | IT |  | 17 | 21 | mA |  | 5 |
| Supply Voltage (Pin 15) | VIN |  |  | 40 | V |  | 4 |
| Collector Supply Voltage (Pin 13) | VC |  |  | 40 | V |  | 4 |
| Output Current, Source or Sink | IO |  |  | 500 | mA | Pins 11, 14 | 4 |
| Power Dissipation | PD |  |  | 1000 | mW | TA=25°C | 4 |
| Power Dissipation | PD |  |  | 2000 | mW | TC=25°C | 4 |
| Storage Temperature | TSTG | -65 |  | 150 | °C |  | 4 |
| Temperature Stability (Reference) | VS |  |  | 0.4 | mV/°C | Over Operating Range, (Note 2) | 4 |
| Unity Gain Bandwidth | B | 0.7 | 1 |  | MHz | TJ=25°C (Note 2) | 4 |

## CAD (KiCad official)

- Symbol: `UC3846L-D16-T`
- Footprint: `Package_DIP:DIP-16_W7.62mm`
- 3D model: DIP-16 (KiCad packages3D, STEP)
- 3D model files: `uc3846l-d16-t-etched.step` / `uc3846l-d16-t-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `uc3846l-d16-t.step` / `uc3846l-d16-t.glb` are the bare package body.

## Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

- **Datasheet:** [UTC(Unisonic Tech) datasheet](docs/uc3846l-d16-t-datasheet.pdf) (10 pp, sha256 `5f227570b8d99fd5`, retrieved 2026-10-23, tier: manufacturer)
- **Extractor:** parts-factory `2.0.0` / `extract_pins 0.3`, primary `claude-sonnet-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/uc3846l-d16-t-datasheet.pdf)