Microchip Technology ATF1502ASV-20AI44

Overview

ATF1502ASV-20AI44 from Atmel is a high-density, electrically-erasable Complex Programmable Logic Device (CPLD) with 32 macrocells, 5 base product terms per macrocell (expandable to 40), 44-pin TQFP package, 20 ns maximum pin-to-pin delay, and industrial temperature support (–40°C to +85°C). It integrates legacy TTL/SSI/MSI logic and supports in-system programming via IEEE 1149.1 JTAG for field reconfiguration in embedded control systems.

For engineers reviewing the ATF1502ASV-20AI44 datasheet, ATF1502ASV-20AI44 pinout, ATF1502ASV-20AI44 application, or ATF1502ASV-20AI44 equivalent, key selection criteria include its 3.0–3.6 V operation, programmable slew rate and open-collector outputs, three global clock inputs, JTAG boundary-scan compliance, and pin-controlled power-down mode enabling sub-5 mA standby current.

Technical Context

The ATF1502ASV-20AI44 implements a flexible macrocell architecture with configurable D/T-latch flip-flops, individual register control signals, and combinatorial or registered output modes. Its enhanced routing includes a 40-signal global bus and regional foldback buses supporting up to nine-product-term sum logic with minimal delay.

It features three dedicated global clock pins (GCLK1–GCLK3), two power-down pins (PD1/PD2), four JTAG boundary-scan pins (TDI/TMS/TCK/TDO), and programmable pin-keeper circuits that eliminate external pull-ups. The device supports both standard and reduced-power macrocell modes, with tRPA = 13–14 ns added to AC timing when reduced-power is enabled.

Key Specifications

Pinout & Package

ATF1502ASV-20AI44 is packaged in a 44-lead Thin Quad Flat Package (TQFP), RoHS-compliant, with 32 user I/O pins, 4 dedicated input pins (GCLR, OE1, OE2, GCLK1–GCLK3 shared), 4 JTAG pins, 4 VCCI pins, and 4 GND pins.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar CPLD applications.

Compared with ATF1502ASV-20AI44, the -20AC44 offers no electrical advantage in industrial settings but lower cost in benign environments, while the -15AI44 delivers measurable timing headroom at the expense of higher ICC1 and reduced power efficiency at low frequencies.

Availability

ATF1502ASV-20AI44 is available at Aetrix Electronics and suitable for industrial automation, legacy system modernization, and automotive body electronics requiring stable component supply across extended lifecycles.

Supply support for ATF1502ASV-20AI44 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 (now part of Microchip Technology) is a semiconductor innovator specializing in non-volatile memory and programmable logic solutions for industrial and embedded markets.

The ATF1502ASV product line was designed to replace obsolete PAL/GAL devices with electrically erasable, in-system programmable CPLDs targeting long-lifecycle industrial control and instrumentation applications.

FAQ

What is the maximum operating frequency of the ATF1502ASV-20AI44?

The ATF1502ASV-20AI44 supports a maximum internal clock frequency of 83.3 MHz under industrial conditions (–40°C to +85°C), as specified by fACNT in Table 13-1. This applies to array clock paths; global clock paths achieve 76.9 MHz. The 20 ns speed grade reflects worst-case pin-to-pin delay, not clock frequency - actual system timing depends on logic depth and routing.

Does the ATF1502ASV-20AI44 support 5 V tolerant I/O?

No, the ATF1502ASV-20AI44 operates strictly at 3.0–3.6 V and is not 5 V tolerant. Input voltage limits are –0.6 V to VCC + 0.75 V DC (with 7.0 V overshoot allowance for <20 ns pulses). Driving it with 5 V signals risks permanent damage. Level-shifting circuitry is required for interfacing with 5 V systems.

How does the pin-keeper feature work on the ATF1502ASV-20AI44?

The ATF1502ASV-20AI44's programmable pin-keeper holds the last driven logic state (high or low) on unused input and I/O pins, preventing floating conditions that cause shoot-through current and EMI. Enabled per-pin in the design file, it replaces external pull-up/down resistors and reduces static power consumption without affecting functional timing.

Can the JTAG pins of the ATF1502ASV-20AI44 be used as general-purpose I/O?

Yes - the JTAG pins (TDI, TMS, TCK, TDO) are fully configurable as user I/O when JTAG boundary-scan and ISP functions are disabled in the design file. However, doing so forfeits in-system programming capability and eliminates boundary-scan test coverage for those pins and associated logic paths.

What is the purpose of the PD1 and PD2 pins on the ATF1502ASV-20AI44?

PD1 and PD2 are dedicated power-down control inputs. When either pin is driven high (with power-down mode enabled in the design), the ATF1502ASV-20AI44 enters a sub-5 mA standby state while latching all internal registers and output states. Inputs other than PD1/PD2 are ignored during power-down, but pin-keeper circuits remain active to prevent floating.