The Miniature Card was an Intel-promoted flash and SRAM memory-card standard introduced in 1995, governed by the Intel Miniature Card Specification Release 1.0 (February 1996). The card measures 35 × 33 × 3.5 mm and uses a 60-pin elastomeric connector — no metal connector is required on the card itself and no ejection mechanism is required on the host, keeping both card and socket costs low. The interface carries a 16-bit parallel data bus with a 25-pin address bus supporting up to 64 MB of linear address space, and accommodates both 5V and 3.3V supply voltages. Although architected primarily for linear Flash memory without requiring ASICs or microcontrollers, the standard also defined DRAM and ROM variants. The format was never widely adopted, being superseded by CompactFlash and SmartMedia, and is now entirely obsolete.
60 Pin Connector Miniature Card
| Pin | Name | Description | Dir |
|---|---|---|---|
| 1 | A18 | Address Bus | IN |
| 2 | A16 | Address Bus | IN |
| 3 | A14 | Address Bus | IN |
| 4 | Vccr | Voltage Refresh | IN |
| 5 | CEH# | Card Enable High Byte | IN |
| 6 | A11 | Address Bus | IN |
| 7 | A9 | Address Bus | IN |
| 8 | A8 | Address Bus | IN |
| 9 | A6 | Address Bus | IN |
| 10 | A5 | Address Bus | IN |
| 11 | A3 | Address Bus | IN |
| 12 | A2 | Address Bus | IN |
| 13 | A0 | Address Bus | IN |
| 14 | RAS# | Row Address Strobe | IN |
| 15 | A24 | Address Bus | IN |
| 16 | A23 | Address Bus | IN |
| 17 | A22 | Address Bus | IN |
| 18 | OE# | Output Enable | IN |
| 19 | D15 | Data Bus | IN/OUT |
| 20 | D13 | Data Bus | IN/OUT |
| 21 | D12 | Data Bus | IN/OUT |
| 22 | D10 | Data Bus | IN/OUT |
| 23 | D9 | Data Bus | IN/OUT |
| 24 | D0 | Data Bus | IN/OUT |
| 25 | D2 | Data Bus | IN/OUT |
| 26 | D4 | Data Bus | IN/OUT |
| 27 | RFU | Reserved for future use | |
| 28 | D7 | Data Bus | IN/OUT |
| 29 | SDA | Serial Data and Address | IN/OUT |
| 30 | SCL | Serial Clock | IN |
| 31 | A19 | Address Bus | IN |
| 32 | A17 | Address Bus | IN |
| 33 | A15 | Address Bus | IN |
| 34 | A13 | Address Bus | IN |
| 35 | A12 | Address Bus | IN |
| 36 | RESET# | Reset | IN |
| 37 | A10 | Address Bus | IN |
| 38 | VS1# | Voltage Sense 1 | OUT |
| 39 | A7 | Address Bus | IN |
| 40 | BS8# | Bus Size 8 | IN |
| 41 | A4 | Address Bus | IN |
| 42 | CEL# | Card Enable Low Byte | IN |
| 43 | A1 | Address Bus | IN |
| 44 | CASL# | Column Address Strobe Low Byte | IN |
| 45 | CASH# | Column Address Strobe High Byte | IN |
| 46 | CD# | Card Detect | OUT |
| 47 | A21 | Address Bus | IN |
| 48 | BUSY# | Ready/Busy | OUT |
| 49 | WE# | Write Enable | IN |
| 50 | D14 | Data Bus | IN/OUT |
| 51 | RFU | Reserved for future use | |
| 52 | D11 | Data Bus | IN/OUT |
| 53 | VS2# | Voltage Sense 2 | OUT |
| 54 | D8 | Data Bus | IN/OUT |
| 55 | D1 | Data Bus | IN/OUT |
| 56 | D3 | Data Bus | IN/OUT |
| 57 | D5 | Data Bus | IN/OUT |
| 58 | D6 | Data Bus | IN/OUT |
| 59 | RFU | Reserved for future use | |
| 60 | A20 | Address Bus | IN |
The following three are separate:
| Name | Description | Dir |
|---|---|---|
| GND | Ground | |
| VCC | Power | |
| CINS# | Card Insertion | OUT |
- Direction is card relative to host device.
Notes
- The Miniature Card connector is elastomeric (pressure-contact): the card itself carries no metal connector, and the host socket requires no ejection mechanism, minimising both card and host cost.
- Card dimensions are 35 × 33 × 3.5 mm (single thickness only).
- Supply voltage is selectable: 5V (standard Vcc) or 3.3V as signalled by VS1#/VS2#.
- The 25-bit address bus (A0–A24) supports a 32 Mword (64 MB) linear address space; smaller cards may not decode the upper address lines and will repeat their address space at card-capacity boundaries.
- The three signals GND, VCC, and CINS# listed in the separate table are routed as dedicated contacts outside the main 60-pin array.
- CINS# makes contact before the 60 main interface pins during insertion and is the last to disconnect during removal, making it suitable for early card-detect logic distinct from CD#.
- The format is entirely obsolete; it was superseded by CompactFlash and SmartMedia in consumer applications.
Signals
- A0–A24 — 25-bit address bus; addresses up to 32 Mwords (64 MB). Cards smaller than 64 MB may not decode upper address lines, causing the address space to repeat at card-capacity boundaries.
- D0–D15 — 16-bit bidirectional data bus; low byte D[7:0], high byte D[15:8].
- CEL# — Card Enable Low Byte: selects the low byte (D[7:0]) for the current bus cycle; not used on DRAM cards.
- CEH# — Card Enable High Byte: selects the high byte (D[15:8]) for the current bus cycle; not used on DRAM cards.
- OE# — Output Enable: asserted by the host to indicate a read cycle.
- WE# — Write Enable: asserted by the host to indicate a write cycle.
- RAS# — Row Address Strobe: latches the row address into DRAM cards.
- CASL# — Column Address Strobe Low Byte: latches the low-byte column address into DRAM cards.
- CASH# — Column Address Strobe High Byte: latches the high-byte column address into DRAM cards.
- RESET# — Card reset; a low-to-high transition causes the card to initialise to a predetermined state.
- BUSY# — Ready/Busy output from card: high = card ready to accept the next command; low = card busy (e.g. Flash erase or program in progress). Flash cards tie this to the device RY/BY# signal; ROM cards hold it permanently high.
- BS8# — Bus Size 8: driven by the host; low = 8-bit host (host must bridge D[15:8] to D[7:0]); high = 16-bit host.
- VS1# — Voltage Sense 1: card grounds this signal to indicate it can operate at 3.3V; must be connected to card GND or left open.
- VS2# — Voltage Sense 2: card grounds this signal to indicate support for a further reduced voltage (value reserved for future definition in Release 1.0 of the spec); must be connected to card GND or left open.
- Vccr — Voltage Refresh: low-current supply used by DRAM cards to maintain self-refresh during sleep mode.
- SDA — I²C Serial Data/Address: used with SCL to read the Attribute Information Structure (AIS) from a serial EEPROM fitted on DRAM cards.
- SCL — I²C Serial Clock: clock signal for reading the AIS EEPROM on DRAM cards (see SDA).
- CD# — Card Detect: grounded on the card; forced low once the card is fully seated. Positioned near the centre of the second contact row so it is one of the last signals to connect during insertion. Not to be confused with CINS#.
- RFU — Reserved for Future Use (pins 27, 51, 59): must be left unconnected.
- GND — Ground (dedicated contact outside the 60-pin array).
- VCC — Card power supply (dedicated contact outside the 60-pin array).
- CINS# — Card Insertion Detect: grounded contact at the front edge of the card; makes contact before the 60 main interface pins during insertion, allowing the host to detect an incoming card before the interface signals are live.
References
- Intel Miniature Card Specification, Release 1.0 (Intel Corporation, February 1996) — primary governing document for this connector.