Texas Instruments TRF7970A BoosterPack, Manual

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TRF7970A
SLOS743L – AUGUST 2011 – REVISED MARCH 2017 www.ti.com
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Detailed Description
Copyright © 2011–2017, Texas Instruments Incorporated
6.15.3.2.10 Regulator and I/O Control Register (0x0B)
Table 6-38 describes the Regulator and I/O Control register.
Table 6-38. Regulator and I/O Control Register (0x0B)
Function: Control the three voltage regulators
Default: 0x87 at POR = H or EN = L
Bit Name Function Description
B7 auto_reg
0 = Manual settings; see B0
to B2 in
Table 6-39 and
Table 6-40
1 = Automatic setting (see
Table 6-41 and Table 6-42 )
Auto system sets V
DD_RF
= V
IN
– 250 mV and V
DD_A
= V
IN
– 250 mV and
V
DD_X
= V
IN
– 250 mV, but not higher than 3.4 V.
B6 en_ext_pa
Support for external power
amplifier
Internal peak detectors are disabled, receiver inputs (RX_IN1 and RX_IN2)
accept externally demodulated subcarrier. At the same time ASK/OOK pin 12
becomes modulation output for external TX amplifier.
B5 io_low
1 = enable low peripheral
communication voltage
When B5 = 1, maintains the output driving capabilities of the I/O pins connected
to the level shifter under low voltage operation. Should be set 1 when V
DD_I/O
voltage is between 1.8 V to 2.7 V.
B4 Unused No function Default is 0.
B3 Unused No function Default is 0.
B2 vrs2
Voltage set MSB voltage
set LSB Vrs3_5 = L: V
DD_RF
, V
DD_A
, V
DD_X
range 2.7 V to 3.4 V; see Table 6-39 and
Table 6-40
B1 vrs1
B0 vrs0
Table 6-39. Supply-Regulator Setting – Manual 5-V System
REGISTER
OPTION BITS SETTING IN CONTROL REGISTER
ACTION
B7 B6 B5 B4 B3 B2 B1 B0
00 1 5-V system
0B 0 Manual regulator setting
0B 0 1 1 1 V
DD_RF
= 5 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 1 1 0 V
DD_RF
= 4.9 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 1 0 1 V
DD_RF
= 4.8 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 1 0 0 V
DD_RF
= 4.7 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 0 1 1 V
DD_RF
= 4.6 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 0 1 0 V
DD_RF
= 4.5 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 0 0 1 V
DD_RF
= 4.4 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
0B 0 0 0 0 V
DD_RF
= 4.3 V, V
DD_A
= 3.4 V, V
DD_X
= 3.4 V
Table 6-40. Supply-Regulator Setting – Manual 3-V System
REGISTER
OPTION BITS SETTING IN CONTROL REGISTER
ACTION
B7 B6 B5 B4 B3 B2 B1 B0
00 0 3-V system
0B 0 Manual regulator setting
0B 0 1 1 1 V
DD_RF
= 3.4 V, V
DD_A
and V
DD_X
= 3.4 V
0B 0 1 1 0 V
DD_RF
= 3.3 V, V
DD_A
and V
DD_X
= 3.3 V
0B 0 1 0 1 V
DD_RF
= 3.2 V, V
DD_A
and V
DD_X
= 3.2 V
0B 0 1 0 0 V
DD_RF
= 3.1 V, V
DD_A
and V
DD_X
= 3.1 V
0B 0 0 1 1 V
DD_RF
= 3.0 V, V
DD_A
and V
DD_X
= 3.0 V
0B 0 0 1 0 V
DD_RF
= 2.9 V, V
DD_A
and V
DD_X
= 2.9 V
0B 0 0 0 1 V
DD_RF
= 2.8 V, V
DD_A
and V
DD_X
= 2.8 V
0B 0 0 0 0 V
DD_RF
= 2.7 V, V
DD_A
and V
DD_X
= 2.7 V