ZHCS761F December 2011 – May 2017 TRF7962A
PRODUCTION DATA.
The input supply voltage mode of the reader must be selected. This is done in the Chip Status Control register (0x00). Bit 0 in register 0x00 selects either 5-V or 3-V input supply voltage. The default configuration is 5 V, which reflects an operating supply voltage range of 4.3 V to 5.5 V. If the supply voltage is below 4.3 V, the 3-V configuration should be used.
The various regulators can be configured to operate in automatic or manual mode. This is done in the
Regulator and I/O Control register (0x0B) (see Table 6-1 and Table 6-2).
| REGISTER ADDRESS | OPTION BITS SETTING IN REGULATOR CONTROL REGISTER(1) | COMMENTS | |||||||
|---|---|---|---|---|---|---|---|---|---|
| B7 | B6 | B5 | B4 | B3 | B2 | B1 | B0 | ||
| Automatic Mode (default) | |||||||||
| 0B | 1 | x | x | x | x | x | 1 | 1 | Automatic regulator setting with 250-mV difference |
| 0B | 1 | x | x | x | x | x | 1 | 0 | Automatic regulator setting with 350-mV difference |
| 0B | 1 | x | x | x | x | x | 0 | 0 | Automatic regulator setting with 400-mV difference |
| Manual Mode | |||||||||
| 0B | 0 | x | x | x | x | 1 | 1 | 1 | VDD_RF = 5 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 1 | 1 | 0 | VDD_RF = 4.9 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 1 | 0 | 1 | VDD_RF = 4.8 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 1 | 0 | 0 | VDD_RF = 4.7 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 0 | 1 | 1 | VDD_RF = 4.6 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 0 | 1 | 0 | VDD_RF = 4.5 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 0 | 0 | 1 | VDD_RF = 4.4 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 0 | 0 | 0 | VDD_RF = 4.3 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| REGISTER ADDRESS | OPTION BITS SETTING IN REGULATOR CONTROL REGISTER(1) | COMMENTS | |||||||
|---|---|---|---|---|---|---|---|---|---|
| B7 | B6 | B5 | B4 | B3 | B2 | B1 | B0 | ||
| Automatic Mode (default) | |||||||||
| 0B | 1 | x | x | x | x | x | 1 | 1 | Automatic regulator setting with 250-mV difference |
| 0B | 1 | x | x | x | x | x | 1 | 0 | Automatic regulator setting with 350-mV difference |
| 0B | 1 | x | x | x | x | x | 0 | 0 | Automatic regulator setting with 400-mV difference |
| Manual Mode | |||||||||
| 0B | 0 | x | x | x | x | 1 | 1 | 1 | VDD_RF = 3.4 V, VDD_A = 3.4 V, VDD_X = 3.4 V |
| 0B | 0 | x | x | x | x | 1 | 1 | 0 | VDD_RF = 3.3 V, VDD_A = 3.3 V, VDD_X = 3.3 V |
| 0B | 0 | x | x | x | x | 1 | 0 | 1 | VDD_RF = 3.2 V, VDD_A = 3.2 V, VDD_X = 3.2 V |
| 0B | 0 | x | x | x | x | 1 | 0 | 0 | VDD_RF = 3.1 V, VDD_A = 3.1 V, VDD_X = 3.1 V |
| 0B | 0 | x | x | x | x | 0 | 1 | 1 | VDD_RF = 3.0 V, VDD_A = 3.0 V, VDD_X = 3.0 V |
| 0B | 0 | x | x | x | x | 0 | 1 | 0 | VDD_RF = 2.9 V, VDD_A = 2.9 V, VDD_X = 2.9 V |
| 0B | 0 | x | x | x | x | 0 | 0 | 1 | VDD_RF = 2.8 V, VDD_A = 2.8 V, VDD_X = 2.8 V |
| 0B | 0 | x | x | x | x | 0 | 0 | 0 | VDD_RF = 2.7 V, VDD_A = 2.7 V, VDD_X = 2.7 V |
The regulator configuration function adjusts the regulator outputs by default to 250 mV below VIN level, but not higher than 5 V for VDD_RF, 3.4 V for VDD_A and VDD_X. This ensures the highest possible supply voltage for the RF output stage while maintaining an adequate PSRR (power supply rejection ratio).
To further improve the PSRR, it is possible to increase the target voltage difference across VDD_X and VDD_A from its default to 350 mV or even 400 mV (for details, see Regulator and I/O Control register 0x0B definition and Table 6-2.)