Analog Devices Inc./Maxim Integrated MAX1840EUB+TG65

Overview

MAX1840EUB+TG65 from Maxim Integrated is a SIM/smart card level translator IC with integrated ±10kV ESD protection, two unidirectional level shifters (CLK, RST), and one bidirectional level shifter (DATA/IO). It operates with DVCC = +1.4V to +5.5V (controller side) and VCC = +1.7V to +5.5V (card side), draws 1.0µA quiescent current, and features SHDN-controlled shutdown for safe SIM insertion/removal in GSM handsets.

For engineers reviewing the MAX1840EUB+TG65 datasheet, MAX1840EUB+TG65 pinout, MAX1840EUB+TG65 application, or MAX1840EUB+TG65 equivalent, this device is selected for low-power multivoltage smart card interfaces requiring guaranteed ESD robustness, automatic supply-loss shutdown, and precise bidirectional data translation without external pull-ups.

Technical Context

The MAX1840EUB+TG65 implements three independent level-shifting paths: CIN→CLK and RIN→RST are unidirectional CMOS-compatible translators; DATA↔IO forms a bidirectional path using internal 20kΩ (DATA-to-DVCC) and 10kΩ (IO-to-VCC) pull-up resistors. All translations function correctly whether DVCC ≥ VCC or DVCC ≤ VCC.

Shutdown is activated by driving SHDN low, which actively pulls CLK, RST, and IO to GND, disables the DATA–IO transfer gate, and reduces total supply current to 0.01µA. ESD protection on CLK, RST, IO, VCC, and GND meets ±10kV IEC 61000-4-2 contact discharge requirements when a 1µF bypass capacitor is used on VCC.

Key Specifications

Pinout & Package

MAX1840EUB+TG65 is housed in a 10-pin µMAX package (3.0mm × 3.0mm, 1.09mm height), pin-compatible with industry-standard 10-pin µMAX footprint and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SIM/smart card level translation applications.

Compared with MAX1841EUB+, MAX1840EUB+TG65 provides dedicated SHDN control for safe SIM insertion but requires an open-drain controller DATA output; compared with MAX3232ESE+, it delivers SIM-specific ESD, level-shifting architecture, and GSM compliance - making it the only valid option for certified SIM interface designs.

Availability

MAX1840EUB+TG65 is available at Aetrix Electronics and suitable for GSM handset design, smart card reader manufacturing, and mixed-voltage SPI bridge applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for MAX1840EUB+TG65 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

Maxim Integrated (now part of Analog Devices) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.

The MAX1840EUB+TG65 belongs to Maxim's SIM/smart card interface product line, designed specifically to simplify multivoltage smart card integration in space-constrained, battery-sensitive portable electronics while meeting stringent GSM certification requirements.

FAQ

What is the primary function of the MAX1840EUB+TG65 in a GSM handset design?

The MAX1840EUB+TG65 serves as a dedicated SIM/smart card level translator and ESD protector in GSM handsets. It shifts logic levels between the baseband processor (DVCC = 1.4V–5.5V) and the SIM card (VCC = 1.7V–5.5V) for CLK, RST, and bidirectional DATA/IO signals, while providing ±10kV ESD protection on all card-facing pins and enabling safe hot-swap via SHDN-controlled shutdown. Its 1.0µA quiescent current and GSM 11.11/11.12 compliance make it essential for certified mobile designs.

Does the MAX1840EUB+TG65 require external pull-up resistors for DATA or IO lines?

No, the MAX1840EUB+TG65 integrates internal pull-up resistors: a 13–28kΩ resistor from DATA to DVCC and a 6.5–14kΩ resistor from IO to VCC. These eliminate the need for external pull-ups in standard open-drain configurations. The values are process-trimmed and temperature-stable, ensuring reliable rise times across the full operating range without board-level component count increase.

How does the SHDN pin on the MAX1840EUB+TG65 improve SIM card insertion safety?

The SHDN pin on the MAX1840EUB+TG65 enables controlled shutdown: when driven low, it actively pulls CLK, RST, and IO to GND and disables the DATA–IO transfer gate. This satisfies GSM 11.11's requirement that all SIM card contacts be at ground potential before insertion. The total supply current drops to 0.01µA, preventing backfeeding and eliminating risk of latch-up or damage during hot-swap - a critical feature absent in generic level shifters.

Can the MAX1840EUB+TG65 translate between 1.8V and 5V logic domains?

Yes, the MAX1840EUB+TG65 supports bidirectional level translation across asymmetric voltage domains: DVCC can be as low as +1.4V (e.g., 1.8V ASIC core) while VCC is +5.0V (standard SIM card), and vice versa. Its architecture guarantees correct logic thresholds (VIL = 0.2×DVCC, VIH = 0.7×DVCC) and output drive (VOH = 0.9×VCC, VOL = 0.4V) regardless of relative supply magnitudes - a key differentiator from basic MOSFET-based translators.

Is the MAX1840EUB+TG65 pin-compatible with other Maxim SIM translators like the MAX1841EUB+?

No, the MAX1840EUB+TG65 is not pin-compatible with the MAX1841EUB+. While both use the same 10-pin µMAX package, Pin 5 is SHDN on MAX1840EUB+TG65 but DDRV on MAX1841EUB+, and Pin 10 is IO on MAX1840EUB+TG65 but unused on MAX1841EUB+. Swapping them without PCB revision will cause functional failure. The MAX1840EUB+TG65 is selected for SHDN-driven hot-swap; MAX1841EUB+ is selected for push-pull controller compatibility.