# AD8232ACPZ-R7

**Analog Devices** · Analog To Digital Converters (ADC) · LFCSP-20(4x4)

AD8232ACPZ-R7 from Analog Devices, in a LFCSP-20(4x4). 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 | HPDRIVE | output | High-pass driver output that connects to the capacitor of the first high-pass filter, driven by the AD8232 to keep HPSENSE at the reference voltage. |
| 2 | +IN | input | Instrumentation amplifier positive input, typically connected to the left arm (LA) electrode. |
| 3 | -IN | input | Instrumentation amplifier negative input, typically connected to the right arm (RA) electrode. |
| 4 | RLDFB | input | Right leg drive feedback input, the feedback terminal for the right leg drive circuit. |
| 5 | RLD | output | Right leg drive output, to which the driven electrode (typically the right leg) is connected. |
| 6 | SW | passive | Fast restore switch terminal, connected to the output of the second high-pass filter. |
| 7 | OPAMP+ | input | Operational amplifier noninverting input. |
| 8 | REFOUT | output | Reference buffer output that serves as the signal reference (virtual ground) for the instrumentation amplifier output and any circuit point needing a reference. |
| 9 | OPAMP- | input | Operational amplifier inverting input. |
| 10 | OUT | output | Operational amplifier output carrying the fully conditioned heart rate signal, which can drive an ADC input. |
| 11 | LOD- | output | Leads off comparator output: in dc leads off mode it is high when the -IN electrode is disconnected and low when connected, and in ac leads off mode it is always low. |
| 12 | LOD+ | output | Leads off comparator output: in dc leads off mode it is high when the +IN electrode is disconnected, and in ac leads off mode it is high when either -IN or +IN is disconnected and low only when both are connected. |
| 13 | SDN | input | Shutdown control input; driving SDN low enters the low power shutdown mode. |
| 14 | AC/DC | input | Leads off mode control input; low selects dc leads off mode and high selects ac leads off mode. |
| 15 | FR | input | Fast restore control input; high enables fast recovery mode, otherwise drive low. |
| 16 | GND | power_in | Power supply ground. |
| 17 | +VS | power_in | Power supply terminal; single-supply operation from 2.0 V to 3.5 V per the features list. |
| 18 | REFIN | input | Reference buffer input, a high impedance terminal used to set the level of the reference buffer. |
| 19 | IAOUT | output | Instrumentation amplifier output terminal. |
| 20 | HPSENSE | input | High-pass sense input for the instrumentation amplifier, connected to the junction of the R and C that sets the dc blocking corner frequency. |
| 21 | EP | passive | Exposed pad (from the footprint; not named in the datasheet pin table). |

## Key specifications

| Parameter | Value |
|---|---|
| Manufacturer | Analog Devices |
| Package | LFCSP-20(4x4) |
| Category | Data Acquisition |
| Pins | 21 |

## Electrical characteristics

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

| Parameter | Symbol | Min | Typ | Max | Unit | Conditions | Page |
|---|---|---|---|---|---|---|---|
| Common-Mode Rejection Ratio, DC to 60 Hz | CMRR | 80 | 86 |  | dB | VCM = 0.35 V to 2.85 V, VDIFF = 0 V | 3 |
| Common-Mode Rejection Ratio, DC to 60 Hz (differential input) | CMRR | 80 |  |  | dB | VCM = 0.35 V to 2.85 V, VDIFF = ±0.3 V | 3 |
| Power Supply Rejection Ratio | PSRR | 76 | 90 |  | dB | VS = 2.0 V to 3.5 V | 3 |
| Offset Voltage (RTI), Instrumentation Amplifier Inputs | VOS |  | 3 | 8 | mV | Instrumentation Amplifier Inputs | 3 |
| Offset Voltage (RTI), DC Blocking Input | VOS |  | 5 | 50 | µV | DC Blocking Input | 3 |
| Input Bias Current | IB |  | 50 | 200 | pA |  | 3 |
| Input Bias Current | IB |  |  | 1 | nA | TA = 0°C to 70°C | 3 |
| Input Offset Current | IOS |  | 25 | 100 | pA |  | 3 |
| Input Offset Current | IOS |  |  | 1 | nA | TA = 0°C to 70°C | 3 |
| Input Voltage Range |  | 0.2 |  |  | V | TA = 0°C to 70°C | 3 |
| DC Differential Input Range | VDIFF | -300 |  | 300 | mV |  | 3 |
| Output Swing |  | 0.1 |  |  | V | RL = 50 kΩ | 3 |
| Gain Error |  |  | 1 | 3.5 | % | VDIFF = −300 mV to +300 mV | 3 |
| Offset Voltage (Operational Amplifier A1) | VOS |  | 1 | 5 | mV |  | 3 |
| Input Bias Current (Operational Amplifier A1) | IB |  |  | 1 | nA | TA = 0°C to 70°C | 3 |
| Input Offset Current (Operational Amplifier A1) | IOS |  |  | 1 | nA | TA = 0°C to 70°C | 3 |
| Input Voltage Range (Operational Amplifier A1) |  | 0.1 |  |  | V |  | 3 |
| Output Voltage Range (Operational Amplifier A1) |  | 0.1 |  |  | V | RL = 50 kΩ | 3 |
| Output Swing (Right Leg Drive Amplifier A2) |  | 0.1 |  |  | V | RL = 50 kΩ | 4 |
| Integrator Input Resistor (Right Leg Drive Amplifier A2) |  | 120 | 150 | 180 | kΩ |  | 4 |
| Offset Error (Reference Buffer A3) | VOS |  |  | 1 | mV | RL > 50 kΩ | 4 |
| Voltage Range (Reference Buffer A3) |  | 0.1 |  |  | V | RL = 50 kΩ | 4 |
| Square Wave Frequency (AC Leads Off Detector) | FAC | 50 | 100 | 175 | kHz |  | 4 |
| Impedance Threshold (AC Leads Off Detector) |  | 10 | 20 |  | MΩ | Between +IN and −IN | 4 |
| On Resistance, Switches S1 and S2 | RON | 8 | 10 | 12 | kΩ |  | 4 |
| Input Voltage (AC/DC and FR) Low | VIL |  |  | 1.24 | V |  | 4 |
| Input Voltage (AC/DC and FR) High | VIH | 1.35 |  |  | V |  | 4 |
| Input Voltage (SDN) Low | VIL |  |  | 2.1 | V |  | 4 |
| Input Voltage (SDN) High | VIH | 0.5 |  |  | V |  | 4 |
| Output Voltage Low (LOD+ and LOD− terminals) | VOL |  |  | 0.05 | V |  | 4 |
| Output Voltage High (LOD+ and LOD− terminals) | VOH | 2.95 |  |  | V |  | 4 |
| Quiescent Supply Current |  |  | 170 | 230 | µA |  | 4 |
| Quiescent Supply Current |  |  |  | 210 | µA | TA = 0°C to 70°C | 4 |
| Shutdown Current |  |  | 40 | 500 | nA |  | 4 |
| Shutdown Current |  |  |  | 100 | nA | TA = 0°C to 70°C | 4 |
| Supply Range |  | 2 |  | 3.5 | V |  | 4 |
| Specified Temperature Range |  | 0 |  | 70 | °C |  | 4 |
| Operational Temperature Range |  | -40 |  | 85 | °C |  | 4 |
| Supply Voltage |  |  |  | 3.6 | V |  | 5 |
| Minimum Voltage, Any Terminal |  | -0.3 |  |  | V |  | 5 |
| Storage Temperature Range |  | -65 |  | 125 | °C |  | 5 |
| Operating Temperature Range |  | -40 |  | 85 | °C |  | 5 |
| Maximum Junction Temperature |  |  |  | 140 | °C |  | 5 |
| Thermal Impedance, Junction-to-Ambient | θJA |  | 48 |  | °C/W | Device in free air on a 4-layer JEDEC board | 5 |
| Thermal Impedance, Junction-to-Case | θJC |  | 4.4 |  | °C/W |  | 5 |
| ESD Rating, Human Body Model |  |  |  | 8 | kV | Human Body Model (HBM) | 5 |
| ESD Rating, Charged Device Model |  |  |  | 1.25 | kV | Charged Device Model (FICDM) | 5 |
| ESD Rating, Machine Model |  |  |  | 200 | V | Machine Model (MM) | 5 |

## CAD (KiCad official)

- Symbol: `AD8232ACPZ-R7`
- Footprint: `Package_DFN_QFN:QFN-20-1EP_4x4mm_P0.5mm_EP2.5x2.5mm`
- 3D model: LFCSP-20(4x4) (KiCad packages3D, STEP)
- 3D model files: `ad8232acpz-r7-etched.step` / `ad8232acpz-r7-etched.glb` carry the MPN laser-etched on the die in a toggleable `Adom.LaserEtch` group (Fusion-ready); `ad8232acpz-r7.step` / `ad8232acpz-r7.glb` are the bare package body.

## Provenance

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

- **Datasheet:** [Analog Devices datasheet](https://jlcpcb.com/api/file/downloadByFileSystemAccessId/8588881946016927744) (28 pp, sha256 `7c205ac952614a6f`, retrieved 2026-10-17, 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/ad8232acpz-r7-datasheet.pdf)