520 Pi Snake

520 : Pi Snake

Design render
  • Author: htfab
  • Description: Voltage divider that generates π volts
  • GitHub repository
  • Clock: 0 Hz

How it works

The blue circle has unit radius and therefore an area of π units. We can enclose it by a polygon with exactly 3.3 units of area, adding the parts marked red. Using precision resistors that meander through the blue and red areas respectively we can construct a voltage divider that subdivides the the 3.3 V power and ground rails to achieve a π V output.

blue line meanders through circle, red line meanders through polygon minus circle

How to test

Measure the voltage between the single analog output pin and ground. It should read approximately π volts.

External hardware

Multimeter or other test equipment

IO

#InputOutputBidirectional
0
1
2
3
4
5
6
7

Analog pins

uaanalogDescription
06voltage output

Chip location

Controller Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Analog Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Analog Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux tt_um_chip_rom (Chip ROM) tt_um_factory_test (TinyTapeout 8 Factory Test) tt_um_oscillating_bones (Oscillating Bones) tt_um_urish_charge_pump (Dickson Charge Pump) tt_um_bgr_agolmanesh (Bandgap Reference) tt_um_tnt_diff_rx (TT08 Differential Receiver test) tt_um_rejunity_vga_logo (VGA Tiny Logo (1 tile)) tt_um_tommythorn_maxbw (Asynchronous Multiplier) tt_um_mattvenn_r2r_dac_3v3 (Analog 8 bit 3.3v R2R DAC) tt_um_urish_simon (Simon Says memory game) tt_um_rebeccargb_universal_decoder (Universal Binary to Segment Decoder) tt_um_mattvenn_rgb_mixer (RGB Mixer demo5) tt_um_rebeccargb_hardware_utf8 (Hardware UTF Encoder/Decoder) tt_um_find_the_damn_issue (Find The Damn Issue) tt_um_brandonramos_VGA_Pong_with_NES_Controllers (VGA Pong with NES Controllers) tt_um_kb2ghz_xalu (4-bit minicomputer ALU) tt_um_rebeccargb_intercal_alu (INTERCAL ALU) tt_um_a1k0n_demo (Demo by a1k0n) tt_um_rburt16_bias_generator (Bias Generator) tt_um_zec_square1 ("SQUARE-1": VGA/audio demo) tt_um_jmack2201 (Sprite Bouncer with Looping Background Options) tt_um_ran_DanielZhu (Dice) tt_um_gfg_development_tinymandelbrot (TinyMandelbrot) tt_um_LnL_SoC (Lab and Lectures SoC) tt_um_htfab_pi_snake (Pi Snake) tt_um_tt08_aicd_playground (AICD Playground) tt_um_toivoh_demo (Sequential Shadows [TT08 demo competition]) tt_um_quarren42_demoscene_top (asic design is my passion) tt_um_crispy_vga (Crispy VGA) tt_um_MichaelBell_canon (TT08 Pachelbel's Canon demo) tt_um_shuangyu_top (Calculator) tt_um_wokwi_407306064811090945 (DDR throughput and flop aperature test) tt_um_08_sws (Sine Wave Synthesizer) tt_um_favoritohjs_scroller (VGA Scroller) tt_um_tt08_wirecube (Wirecube) tt_um_vga_glyph_mode (Glyph Mode) tt_um_a1k0n_vgadonut (VGA donut) tt_um_roy1707018 (RO) tt_um_analog_factory_test (TT08 Analog Factory Test) tt_um_sign_addsub (CMOS design of 4-bit Signed Adder Subtractor) tt_um_tinytapeout_logo_screensaver (VGA Screensaver with Tiny Tapeout Logo) tt_um_patater_demokit (Patater Demo Kit Waggling Rainbow on a Chip) tt_um_algofoogle_tt08_vga_fun (TT08 VGA FUN!) tt_um_simon_cipher (simon_cipher) tt_um_thexeno_rgbw_controller (Color Controller) tt_um_demosiine_sda (DemoSiine) tt_um_bytex64_munch (Munch) tt_um_alexjaeger_ringoscillator (5MHz Ring Oscillator) tt_um_cfib_demo (cfib Demoscene Entry) tt_um_wokwi_407852791999030273 (Simple 8 Bit ALU) tt_um_Richard28277 (4-bit ALU) tt_um_betz_morse_keyer (Morse Code Keyer) tt_um_nvious_graphics (nVious Graphics) tt_um_tiny_pll (Tiny PLL) tt_um_ezchips_calc (8-Bit Calculator) tt_um_hack_cpu (HACK CPU) tt_um_noritsuna_Vctrl_LC_oscillator (Voltage Controlled LC-Oscillator) tt_um_ring_divider (Divided Ring Oscillator) tt_um_2048_vga_game (2048 sliding tile puzzle game (VGA)) tt_um_morningjava_r2r_from_matt (Bucket Brigade) tt_um_ephrenm_tsal (TSAL_TT) tt_um_kapilan_alarm (Alarm Clock) tt_um_stochastic_addmultiply_CL123abc (Stochastic Multiplier, Adder and Self-Multiplier) tt_um_wokwi_407760296956596225 (tt08-octal-alu) tt_um_dlfloatmac (DL float MAC) tt_um_wakki_0123_Raw_Transistors (Raw_Transistors) tt_um_faramire_rotary_ring_wrapper (Rotary Encoder WS2812B Control) tt_um_devstdin_LDO_OSC (LDO BG IREF OSC) tt_um_frequency_counter (Frequency Counter SSD1306 OLED) tt_um_rom_test (TT08 SKY130 ROM 'YOLO' Test) tt_um_i2c_peripheral_stevej (i2c peripherals: leading zero count and fnv-1a hash) tt_um_yuri_panchul_schoolriscv_cpu_with_fibonacci_program (schoolRISCV CPU with Fibonacci program) tt_um_yuri_panchul_adder_with_flow_control (Adder with Flow Control) tt_um_brailliance (Brailliance) tt_um_nyan (nyan) tt_um_MichaelBell_mandelbrot (VGA Mandelbrot) tt_um_ssp_opamp (2-stage Opamp Designs) tt_um_fountaincoder_top_ad (pulse_add) tt_um_edwintorok (Rounding error) tt_um_mac (MAC) tt_um_dpmu (DPMU) tt_um_JAC_EE_segdecode (7 Segment Decode) tt_um_wokwi_408118380088342529 (Traffic-light-sequence) tt_um_shiftreg_test (TT08 SKY130 Shift Register 'YOLO' Test) tt_um_yuri_panchul_sea_battle_vga_game (Sea Battle) tt_um_benpayne_ps2_decoder (PS2 Decoder) tt_um_meriac_play_tune (Super Mario Tune on A Piezo Speaker) tt_um_comm_ic_bhavuk (Comm_IC) tt_um_daosvik_aesinvsbox (AES Inverse S-box) tt_um_wokwi_408216451206371329 (Logic Test) tt_um_micro_tiles_container (Micro tile container) tt_um_cattuto_sr_latch (TT08 - 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