Microchip Technology ATF20V8B-7JC

Overview

ATF20V8B-7JC from Atmel is a high-performance, electrically-erasable programmable logic device (PLD) in 28-lead PLCC packaging, delivering 7.5 ns pin-to-pin propagation delay, 5V ±5% operation, and commercial temperature range (0°C to 70°C). It implements registered, complex, or simple PAL emulation with eight macrocells, each configurable as input, combinatorial I/O, or registered output - used in legacy system upgrades, glue logic consolidation, and industrial control state machines.

For engineers reviewing the ATF20V8B-7JC datasheet, ATF20V8B-7JC pinout, ATF20V8B-7JC application, or ATF20V8B-7JC equivalent, this page provides verified functional architecture, mode-specific timing, power consumption under active/standby conditions, PLCC package mechanical data, and direct PAL-family replacement guidance - all confirmed for the exact ATF20V8B-7JC variant.

Technical Context

The ATF20V8B-7JC uses Atmel's Flash-based CMOS process to implement a universal 20-input, 8-output PLD architecture supporting three automatic configuration modes: Registered (emulates 20R8/20RP8), Complex (emulates 20L8/20H8), and Simple (emulates 14L8/16L6). Each macrocell allocates up to eight product terms to its sum term and supports output enable via dedicated OE pin or product-term control.

It features internal input/I/O pull-up resistors, 20-year data retention, 100 erase/write cycles, 2,000V ESD protection, and 200 mA latchup immunity. Power supply current is 60 mA (standby) and 80–110 mA (active, f = 15 MHz) at VCC = 5V ±5%, with tS = 5 ns setup and tCO = 5 ns clock-to-output under commercial conditions.

Key Specifications

Pinout & Package

ATF20V8B-7JC is housed in a 28-lead Plastic J-Leaded Chip Carrier (PLCC) package per JEDEC MS-018 AB, with 11.43 mm × 11.43 mm body, 0.51 mm max lead thickness, and 1.27 mm pitch. Pin 1 identifier is marked by a corner chamfer.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable logic device applications.

Compared with GAL20V8-15LPN, ATF20V8B-7JC offers field-upgradable logic and tighter timing; compared with ATF20V8B-10JC, it delivers 2.5 ns faster path delay at the cost of higher active current - making it optimal for time-critical legacy replacements where reprogrammability is essential.

Availability

ATF20V8B-7JC is available at Aetrix Electronics and suitable for industrial control logic, legacy system glue logic replacement, automated test equipment, and medical instrumentation interface applications requiring stable component supply and long-term obsolescence management.

Supply support for ATF20V8B-7JC includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Atmel Corporation was a U.S.-based semiconductor manufacturer specializing in microcontrollers, nonvolatile memory, and programmable logic, acquired by Microchip Technology in 2016.

The ATF20V8B series was designed as a Flash-based, drop-in replacement for industry-standard 24-pin PAL devices, targeting legacy system modernization and long-lifecycle industrial electronics.

FAQ

What is the maximum clock frequency supported by ATF20V8B-7JC in Registered Mode?

The ATF20V8B-7JC supports a maximum external feedback clock frequency of 100 MHz in Registered Mode, calculated as 1/(tS + tCO) = 1/(5 ns + 5 ns). This assumes nominal 5V ±5% supply and commercial temperature conditions. The actual achievable frequency depends on board layout, load capacitance, and signal integrity - the 100 MHz value represents the guaranteed minimum timing specification, not an overclocking limit. ATF20V8B-7JC maintains this rating across all eight macrocells simultaneously.

Does ATF20V8B-7JC require external pull-up resistors on input pins?

No, ATF20V8B-7JC does not require external pull-up resistors on input or I/O pins because it integrates internal weak pull-up resistors on all such terminals. These ensure defined logic-high states when pins are left unconnected or tri-stated, eliminating the need for discrete components in most designs. However, external drivers must be capable of overdriving these internal pull-ups - TTL-compatible sources meet this requirement. ATF20V8B-7JC's internal pull-ups are intentionally weak to avoid contention during active driving.

Can ATF20V8B-7JC be programmed using standard PLD programmers?

Yes, ATF20V8B-7JC is fully compatible with industry-standard PLD programmers that support Atmel's Flash-based PLDs, including Data I/O PS-28/PS-30, BP Microsystems Series, and Xeltek SuperPro programmers. Programming follows JEDEC file format and requires no special voltage sequences beyond standard 5V VCC and 12.5V VPP (if used for enhanced verification). ATF20V8B-7JC does not require UV erasure or socket removal - in-system programming is supported via standard ISP protocols.

What is the purpose of the 64-bit electronic signature word in ATF20V8B-7JC?

The 64-bit electronic signature word in ATF20V8B-7JC provides user-accessible nonvolatile memory that remains readable even after the security fuse is programmed. It is intended for storing project identifiers, version numbers, calibration constants, or manufacturing traceability data - not for logic configuration. This feature allows unique device identification and field diagnostics without compromising protected fuse pattern integrity. ATF20V8B-7JC exposes this memory independently of the main logic array, ensuring persistent access throughout the device's lifetime.

How does the power-up reset behavior of ATF20V8B-7JC affect system initialization?

ATF20V8B-7JC performs an asynchronous power-up reset that forces all registers to low state when VCC crosses VRST (3.8–4.5 V), resulting in high registered outputs at power-on. This guarantees deterministic initialization for state machines but requires monotonic VCC ramp-up and adherence to tPR (600–1000 ns) before clock activation. Failure to meet these conditions may cause metastability. ATF20V8B-7JC's reset behavior is intrinsic to its Flash architecture and cannot be disabled or configured - it is a hardwired feature critical for legacy PAL compatibility.