This page describes the performance of different passive components with the voltage regulators on Sulu and Spock PCBs.
Introduction
The Spock and Sulu PCBs have voltage regulators so that a 3 V battery can power SCuM, which takes up to 2 V. The voltage regulators have been noisier and less efficient than expected.
Component selection
Friendly name | Model number | Designator | Notes | Datasheet |
spock 10 uF cap | GRJ155R60J106ME11D | C_1.1_IN1, C_1.1_OUT1, C_1.8_IN2 , C_1.8_OUT2 | ||
old 10 uF cap | CL05A106MP8NUB8 | C_1.1_IN1, C_1.8_IN2 | ||
new 10 uF cap | GRM155R60J106ME15D | C_1.1_IN1, C_1.1_OUT1, C_1.8_IN2 , C_1.8_OUT2 | Recommended on datasheet | |
100 uF cap | GRM21BR60E107ME15L | C_1.1_OUT1, C_1.8_OUT2 | ||
old inductor | MLZ1005M2R2WT000 | L1, L2 | ||
new inductor | 74438343022 | L1, L2 | Recommended on datasheet | |
1.1V DC-DC | S-85S1AB11-I6T1U | U3 | https://www.ablic.com/en/doc/datasheet/switching_regulator/S85S1A_E.pdf | |
1.8V DC-DC | S-85S1AB18-I6T1U | U2 | https://www.ablic.com/en/doc/datasheet/switching_regulator/S85S1A_E.pdf |
Note that the 1.1V DC-DC converters were missing so 1.0V DC-DC converters were used as a substitute.
Boards
Friendly name | Designator | Board | L1, L2 | C_1.x_INy | C_1.x_OUTy | VBAT converter | VDDD converter |
Recommended components | DC1 | Sulu v1.0 | 74438343022 | GRM155R60J106ME15D | GRM155R60J106ME15D | S-85S1AB18-I6T1U | S-85S1AB10-I6T1U |
Spock components | DC2 | Sulu v1.0 | MLZ1005M2R2WT000 | GRJ155R60J106ME11D | GRJ155R60J106ME11D | S-85S1AB18-I6T1U | S-85S1AB10-I6T1U |
L6/L7 | Sulu v1.0 | MLZ1005M2R2WT000 | CL05A106MP8NUB8 | GRM21BR60E107ME15L | S-85S1AB18-I6T1U | S-85S1AB11-I6T1U |
Figures
Waveforms
DC1
DC2
L6
I-V measurements
Board | V_ext (V) | R_load (k Ohm) | R_ext (k Ohm) | I_ext (mA) | V_bat (V) | I_bat (mA) | P_ext (mW) | P_bat (mW) | P_bat/P_ext (%) |
DC1 | 3 | 11.94 | 0 | 1.389 | 1.791 | 0.1506 | 4.167 | 0.269725 | 6% |
DC1 | 3 | 5.25 | 0 | 1.502 | 1.765 | 0.3365 | 4.506 | 0.593923 | 13% |
DC1 | 3 | 1.194 | 0 | 2.304 | 1.783 | 1.494 | 6.912 | 2.663802 | 39% |
DC2 | 3 | 11.94 | 0 | 1.781 | 1.799 | 0.1509 | 5.343 | 0.271469 | 5% |
DC2 | 3 | 5.25 | 0 | 1.951 | 1.8 | 0.3431 | 5.853 | 0.61758 | 11% |
DC2 | 3 | 1.194 | 0 | 2.95 | 1.779 | 1.483 | 8.850 | 2.638257 | 30% |
L6 | 3 | 11.94 | 0 | 1.88 | 1.757 | 0.147 | 5.640 | 0.258279 | 5% |
L6 | 3 | 5.25 | 0 | 2.1 | 1.821 | 0.347 | 6.300 | 0.631887 | 10% |
L6 | 3 | 1.194 | 0 | 3.15 | 1.814 | 1.52 | 9.450 | 2.75728 | 29% |