SLOS743M August 2011 – March 2020 TRF7970A
PRODUCTION DATA.
Table 6-25 describes the Chip Status Control register.
| Function: Control of Power mode, RF on or off, Active or Passive mode, Direct mode | |||
| Default: 0x01, preset at EN = L or POR = H | |||
| Bit | Name | Function | Description |
| B7 | stby | 1 = Standby mode | Standby mode keeps all supply regulators and the 13.56-MHz SYS_CLK oscillator running. (Typical start-up time to full operation is 100 µs.) |
| 0 = Active mode | Active mode (default) | ||
| B6 | direct | 1 = Direct mode 0 or 1 | Provides user direct access to AFE (direct mode 0) or allows user to add custom framing (direct mode 1). Bit 6 of the ISO Control register must be set by user before entering direct mode 0 or 1. |
| 0 = Direct l 2 (default) | Uses SPI or parallel communication with automatic framing and ISO decoders | ||
| B5 | rf_on | 1 = RF output active | Transmitter on, receivers on |
| 0 = RF output not active | Transmitter off | ||
| B4 | rf_pwr | 1 = Half output power | TX_OUT (pin 5) = 8-Ω output impedance P = 100 mW (20 dBm) at 5 V, P = 33 mW (+15 dBm) at 3.3 V |
| 0 = Full output power | TX_OUT (pin 5) = 4-Ω output impedance P = 200 mW (+23 dBm) at 5 V, P = 70 mW (+18 dBm) at 3.3 V | ||
| B3 | pm_on | 1 = Selects aux RX input | RX_IN2 input is used |
| 0 = Selects main RX input | RX_IN1 input is used | ||
| B2 | Reserved | ||
| B1 | rec_on | 1 = Receiver activated for external field measurement | Forced enabling of receiver and TX oscillator. Used for external field measurement. |
| 0 = Automatic enable | Allows enable of the receiver by bit 5 of this register (0x00) | ||
| B0 | vrs5_3 | 1 = 5-V operation
0 = 3-V operation |
Selects the VIN voltage range |