# L9788TR

**STMicroelectronics** · Power Management Specialized - PMIC · LQFP-100(14x14)

L9788TR from STMicroelectronics, in a LQFP-100(14x14). 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 | FLW_IN_P | power_in | Flying wheel input voltage, positive terminal; the datasheet gives no electrical limits for this pin. |
| 2 | FLW_IN_N | power_in | Flying wheel input voltage, negative terminal; the datasheet gives no electrical limits for this pin. |
| 3 | FLW_OUT | output | Flying wheel output voltage (digital output); no electrical limits given. |
| 4 | LIN_TX | input | LIN data input (transmit path to the LIN driver); no electrical limits given. |
| 5 | LIN_RX | output | LIN data output (receive path from the LIN driver); no electrical limits given. |
| 6 | LIN | bidirectional | LIN bus driver output, listed as power in/out; no electrical limits given. |
| 7 | VB_STBY | power_in | Supply voltage for the standby function; no electrical limits given. |
| 8 | VSENSE4_MON | input | Monitor analog input for the tracking sensor supply; no electrical limits given. |
| 9 | Key in | power_in | Key signal input, listed as power in; no electrical limits given. |
| 10 | Wake in | power_in | Wake-up signal input, listed as power in; no electrical limits given. |
| 11 | MRD | power_out | Main relay driver output voltage; no electrical limits given. |
| 12 | INJ3 | power_out | Injector driver output voltage; no electrical limits given. |
| 13 | INJ34_PGND | power_in | Ground for injector drivers 3 and 4. |
| 14 | INJ4 | power_out | Injector driver output voltage; no electrical limits given. |
| 15 | STR1_DRN | power_out | Configurable high/low side drain voltage for driver 1; no electrical limits given. |
| 16 | STR1_SRC | power_out | Configurable high/low side source voltage for driver 1; no electrical limits given. |
| 17 | STR2_SRC | power_out | Configurable high/low side source voltage for driver 2; no electrical limits given. |
| 18 | STR2_DRN | power_out | Configurable high/low side drain voltage for driver 2; no electrical limits given. |
| 19 | STR3_DRN | power_out | Configurable high/low side drain voltage for driver 3; no electrical limits given. |
| 20 | STR3_SRC | power_out | Configurable high/low side source voltage for driver 3; no electrical limits given. |
| 21 | LED1 | power_out | LED driver output voltage; no electrical limits given. |
| 22 | LED2 | power_out | LED driver output voltage; no electrical limits given. |
| 23 | GND | power_in | Ground. |
| 24 | WDA | bidirectional | Watchdog input/output. |
| 25 | RSTN | output | Reset output for VDD5. |
| 26 | SEO_OUT | output | SEO output pin (digital output). |
| 27 | VDD_IO | power_in | Dedicated supply for FLW_OUT, MSC_DO, LIN_RX and CAN_RX; no voltage limits given. |
| 28 | MSC_DO | output | MSC digital I/O (digital output). |
| 29 | INJ_ENA | input | Enable input for the injector drivers. |
| 30 | EN_N | input | Enable signal input (N side). |
| 31 | EN_P | input | Enable signal input (P side). |
| 32 | IGN1 | power_out | Ignition pre-driver output voltage; no electrical limits given. |
| 33 | IGN2 | power_out | Ignition pre-driver output voltage; no electrical limits given. |
| 34 | RLY1 | power_out | Relay driver output voltage; no electrical limits given. |
| 35 | RLY2 | power_out | Relay driver output voltage; no electrical limits given. |
| 36 | INJ1 | power_out | Injector driver output voltage; no electrical limits given. |
| 37 | INJ1_PGND | power_in | Ground for injector driver 1. |
| 38 | INJ2_PGND | power_in | Ground for injector driver 2. |
| 39 | INJ2 | power_out | Injector driver output voltage; no electrical limits given. |
| 40 | RLY3 | power_out | Relay driver output voltage; no electrical limits given. |
| 41 | RLY4 | power_out | Relay driver output voltage; no electrical limits given. |
| 42 | RLY5 | power_out | Relay driver output voltage; no electrical limits given. |
| 43 | IGN3 | power_out | Ignition pre-driver output voltage; no electrical limits given. |
| 44 | IGN4 | power_out | Ignition pre-driver output voltage; no electrical limits given. |
| 45 | MSC_EN | input | MSC digital I/O enable (digital input). |
| 46 | MSC_CK_P | input | MSC clock, positive (digital input). |
| 47 | MSC_CK_N | input | MSC clock, negative (digital input). |
| 48 | MSC_DI_P | input | MSC data input, positive (digital input). |
| 49 | MSC_DI_N | input | MSC data input, negative (digital input). |
| 50 | GND1 | power_in | Power ground, shorted to GND by the package. |
| 51 | PRD5_GATE | power_out | Gate voltage output of general purpose pre-driver 5. |
| 52 | PRD5_DRN | power_in | Feedback voltage input (drain) of general purpose pre-driver 5. |
| 53 | PRD4_DRN | power_in | Feedback voltage input (drain) of general purpose pre-driver 4. |
| 54 | PRD4_GATE | power_out | Gate voltage output of general purpose pre-driver 4. |
| 55 | PRD2_GATE | power_out | Gate voltage output of general purpose pre-driver 2. |
| 56 | PRD2_DRN | power_in | Feedback voltage input (drain) of general purpose pre-driver 2. |
| 57 | PRD3_DRN | power_in | Feedback voltage input (drain) of general purpose pre-driver 3. |
| 58 | PRD3_GATE | power_out | Gate voltage output of general purpose pre-driver 3. |
| 59 | PRD1_GATE | power_out | Gate voltage output of general purpose pre-driver 1. |
| 60 | PRD1_DRN | power_in | Feedback voltage input (drain) of general purpose pre-driver 1. |
| 61 | IGN6 | power_out | Ignition pre-driver output voltage; no electrical limits given. |
| 62 | IGN5 | power_out | Ignition pre-driver output voltage; no electrical limits given. |
| 63 | SOL2 | power_out | Valve driver output voltage; no electrical limits given. |
| 64 | SOL12_PGND | power_in | Ground for valve drivers 1 and 2. |
| 65 | SOL1 | power_out | Valve driver output voltage; no electrical limits given. |
| 66 | VSENSE3 | power_out | 5 V tracking sensor supply output voltage. |
| 67 | VSENSE2 | power_out | 5 V tracking sensor supply output voltage. |
| 68 | VSENSE1 | power_out | 5 V tracking sensor supply output voltage. |
| 69 | VPRE | power_out | Pre-buck regulator output voltage. |
| 70 | PDR_GND | power_in | Ground pin for the predriver supply feedback input. |
| 71 | AD_TEST | output | AD test pin (analog output). |
| 72 | VDD5_IN | power_in | 5 V regulator feedback voltage input. |
| 73 | VDD5_GATE | power_out | Pre-driver output for the 5 V linear regulator. |
| 74 | RSTC | output | Reset output for the VDDIO supply. |
| 75 | GND | power_in | Ground. |
| 76 | Boost_G | power_out | Boost low-side gate voltage output. |
| 77 | VBAT_Sense | power_in | Battery supply voltage sense input. |
| 78 | VB_IN | power_in | Battery supply voltage input. |
| 79 | CP | power_out | Charge pump output. |
| 80 | Buck_C_BST | power_out | Bootstrap capacitor pin for the buck regulator. |
| 81 | Buck_SW | power_out | Buck switching pin. |
| 82 | VB_IN_SW | power_in | Buck regulator supply voltage input. |
| 83 | CURR_Sense_O2H2 | output | O2 heater driver 2 output current value (analog output). |
| 84 | O2H2_PGNDB | power_in | Ground for O2 heater driver 2, B side. |
| 85 | O2H2B | power_out | O2 heater driver 2, B output voltage. |
| 86 | O2H2A | power_out | O2 heater driver 2, A output voltage. |
| 87 | O2H2_PGNDA | power_in | Ground for O2 heater driver 2, A side. |
| 88 | O2H1_PGNDB | power_in | Ground for O2 heater driver 1, B side. |
| 89 | O2H1B | power_out | O2 heater driver 1, B output voltage. |
| 90 | O2H1A | power_out | O2 heater driver 1, A output voltage. |
| 91 | O2H1_PGNDA | power_in | Ground for O2 heater driver 1, A side. |
| 92 | VDD_CAN | power_in | CAN supply, 5 V. |
| 93 | CURR_Sense_O2H1 | output | O2 heater driver 1 output current value (analog output). |
| 94 | CANH | bidirectional | CANH bus output (power in/out). |
| 95 | CANL | bidirectional | CANL bus output (power in/out). |
| 96 | CAN_RX | bidirectional | CAN receive data output (digital in/out). |
| 97 | GND | power_in | Ground. |
| 98 | CAN_TX | input | CAN transmit data input. |
| 99 | VB_CAN | power_in | CAN enable signal supply input. |
| 100 | GND_CAN | power_in | CAN ground. |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | STMicroelectronics |
| Package | LQFP-100(14x14) |
| Category | Power Supply Chip |
| Pins | 100 |

## CAD (KiCad official)

- Symbol: `L9788TR`
- Footprint: `Package_QFP:LQFP-100_14x14mm_P0.5mm`
- 3D model: LQFP-100(14x14) (KiCad packages3D, STEP)
- 3D model files: `l9788tr-etched.step` / `l9788tr-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `l9788tr.step` / `l9788tr.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [STMicroelectronics datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588925414081507328) (12 pp, sha256 `ed97c1ea9c8775f2`, retrieved 2026-10-12, tier: lcsc)
- **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/l9788tr-datasheet.pdf)