| Pin | Name | Description |
|---|---|---|
| 1 | GND | Charger/System Ground |
| 2 | V_OUT | Accessory Output Supply. (3.4V...10V - 50mA) |
| 3 | XMIC | External Microphone Input and Accessory Identification |
| 4 | EXT_RF | External RF Control Input |
| 5 | TX | FBUS Transmit (N/C in 1610?) |
| 6 | MBUS | Serial Control Bus |
| 7 | BENA | Not Connected |
| 8 | SGND | Signal Ground |
| 9 | XEAR | External Speaker and Mute Control |
| 10 | Hook | Hook Signal |
| 11 | RX | FBUS Receive (N/C in 1610?) |
| 12 | V_IN | Charging Supply Voltage (Max 16V) |
XMIC: External Microphone Input and Accessory Identification
| U low | U high | Description |
|---|---|---|
| 1.15 V | 1.4 V | Compact Handsfree Unit Connected |
| 1.7 V | 2.05 | Headset Adapter Connected |
| 2.22 V | 2.56 V | Infra Red Link Conneceted |
EXT_RF: External RF Control Input
| U low | U high | Description |
|---|---|---|
| 0.0 V | 0.5 V | External RF in use |
| 2.4 V | 3.2 V | Internal Antenna in use |
MBUS: Serial Control Bus
| U low | U high | Description |
|---|---|---|
| 0.0 V | 0.5 V | Logic Low Level |
| 2.4 V | 3.2 V | Logic High Level |
XEAR: External Speaker and Mute Control
| U low | U high | Description |
|---|---|---|
| 0.0 V | 0.5 V | Mute ON (HF Speaker Mute) |
| 1.0 V | 1.7 V | Mute OFF (HF Speaker Active) |
Hook: Hook Signal
| U low | U high | Description |
|---|---|---|
| 0.0 V | 0.5 V | Hook Off (Handset in Use) |
| 2.4 V | 3.2 V | Hook On (Handset in Use) |