MX25U4033EZUI-12G connection guide
MX25U4033EZUI-12G (USON-8 (4 × 4)) connection guide. Power, ground and chip select. Single SPI and identification.
USON-8 (4 × 4)
9 contacts Current packagePower, ground and chip select
RequiredUse a regulated 1.8 V supply and a host with compatible 1.8 V I/O. If the host uses 3.3 V or 5 V, use a level translator that meets the flash and host thresholds, speed and lane direction requirements. A supply adapter alone does not translate signals.
With power off, connect common ground and place C1 (100 nF ceramic) close to VCC and GND. R1 (10 kΩ) is an example pull-up from CS# to flash VCC; the host still drives CS# during transfers.
Keep the exposed metal clear of PCB copper, including traces and pads. Maintain at least 0.2 mm separation from the terminals. Use pin 4 for GND.
- 1.8 V
- Regulator output
- C1.1
- R1.1
- Ground
- Supply return
- Host ground
- C1.2
- CS# idle bias
- →
- R1.2
Bench checks
- Measure 1.65–2.00 V across the flash supply pins. Budget at least 25 mA for flash program and erase current, plus other loads on the rail.
- With the host outputs high impedance during supply transitions, check that CS# follows VCC. Wait at least 300 µs after VCC reaches 1.65 V before selecting the flash. Avoid driving any flash line from a powered host while flash power is off.
Macronix PM1755 rev. 1.9 · §§3–4, 11, 13–14 and Tables 13, 15. The 10 kΩ pull-up is an example value.
Connection scenarios
Dual I/O read
Use the same pins as single SPI, but route SIO0 and SIO1 to bidirectional host lines. The flash receives the opcode on SIO0, then receives the address and returns data over both lines.
Complete the required power step first.
For a dedicated non-quad design, verify QE = 0. If WP# and HOLD# are unused, their internal pull-high circuits are available; optional 10 kΩ pull-ups give defined external bias.
- CS#
- Host CS#
- →
- SCLK
- Host SCLK
- →
- SI/SIO0
- Host IO0
- SO/SIO1
- Host IO1
- Ground
- Host ground
Bench checks
- Use 2READ (BBh): single-lane opcode, 24 address bits over two lanes, then four dummy clocks. Release the host data outputs before the flash drives them.
- Compare the result with a single SPI read at the same address before increasing SCLK. 2READ is rated up to 80 MHz under Table 14 conditions.
Macronix PM1755 rev. 1.9 · §§8–10 and Table 14; Figs. 16–22 for identification and read sequences.
USON-8 (4 × 4) wiring map
Dashed outline shows the underside pad schematically. See the package drawing for the footprint.
6 · SCLK
Host clock. The flash samples input on rising edges and changes output on falling edges. Use SPI mode 0 or 3.
- SCLK
- Host SCLK
- →
Models and documents
PM1755 rev. 1.9 lists five orderable package codes: M1, ZU, ZB, ZN and BA. Select the actual package before wiring; USON and WSON exposed-metal rules differ.
- MX25U4033EZUI-12G
- USON-8 (4 × 4) · −40 to +85 °C · speed code 12 (command-dependent limits) · RoHS compliant and halogen-free.
- Macronix MX25U4033E datasheet (PDF)· PM1755 rev. 1.9 · 12 January 2016 · pinout p. 8, ordering p. 62, package outlines pp. 64–68.
- Datasheet provenance (JSON)· Official download URL, revision, applicable order codes and SHA-256.
- Macronix models and reference designs· Manufacturer simulation models for M1, ZU, ZB, ZN and BA.
