Microchip Technology TC7662ACPA

Overview

TC7662ACPA from Microchip Technology is a pin-compatible charge pump DC-DC voltage converter IC that inverts +3V to +18V input to -3V to -18V output using only two external capacitors-no inductors required. It delivers up to 40mA output current, features 12kHz nominal oscillator frequency, 40Ω typical output source resistance at 20mA, and operates in 0°C to +70°C commercial temperature range. It is used in laptop computers and µP-based controllers for compact dual-rail power generation.

For engineers reviewing the TC7662ACPA datasheet, TC7662ACPA pinout, TC7662ACPA application, or TC7662ACPA equivalent, key selection criteria include its wide 3–18V input range, no-external-diode architecture, low 40Ω output impedance at 20mA load, oscillator frequency adjustability via OSC pin, and compatibility with legacy TC7660 designs requiring higher output current and lower dropout.

Technical Context

The TC7662ACPA implements a four-switch MOSFET charge pump topology controlled by an internal oscillator and flip-flop-driven level shifters. Its switching action alternates between charging CP to VDD and transferring inverted charge to CR, enabling efficient voltage inversion without magnetic components.

Pin 7 (OSC) allows external capacitor-based frequency tuning-adding capacitance lowers oscillator frequency (e.g., 100pF reduces 12kHz to ~2kHz), enabling optimized efficiency at light loads while requiring proportional increase in CP/CR values to maintain low output impedance.

Key Specifications

Pinout & Package

TC7662ACPA is housed in an 8-pin PDIP (Plastic Dual In-line Package) with 0.300-inch width, standard through-hole mounting, and RoHS-compliant lead finish per Microchip DS21468B.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar charge pump voltage inverter applications.

Compared with LTC1044CSW#PBF and ICL7662CPA, TC7662ACPA provides 2× higher output current, 20% wider input range, and oscillator tunability-making it optimal for new designs requiring robust negative rail generation without inductors or diodes.

Availability

TC7662ACPA is available at Aetrix Electronics and suitable for laptop computers, disk drives, process instrumentation, and µP-based controllers requiring stable component supply across commercial temperature grades.

Supply support for TC7662ACPA 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

Microchip Technology Inc. is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and power management ICs, with global manufacturing and quality certifications including ISO/TS-16949.

The TC7662A product line was designed specifically for compact, inductorless DC-DC voltage inversion in space-constrained portable and embedded systems-emphasizing pin compatibility, wide input range, and ease of implementation with minimal external components.

FAQ

What is the maximum output current capability of the TC7662ACPA?

The TC7662ACPA delivers up to 40mA of continuous output current under specified conditions (VDD = 15V, TA = +25°C). At higher temperatures or lower input voltages, derating applies-e.g., output current drops to ~30mA at 70°C ambient. The device sustains short-circuit conditions continuously only at VDD ≤ 5.5V; above that, transient protection is recommended. This performance is confirmed in DS21468B Electrical Characteristics tables and Typical Characteristics curves.

Can the TC7662ACPA generate positive voltage doubling?

Yes, the TC7662ACPA can be configured for positive voltage doubling using external diodes and capacitors as shown in Figure 4-6 of DS21468B. In this mode, it produces approximately (2 × VDD) – (2 × VF), where VF is the combined forward voltage of two diodes. Output impedance rises to ~60Ω at 10mA load (VDD = 5V), making it suitable for moderate-current applications like LCD bias or low-power logic level shifting-but not for high-current digital rails.

Does the TC7662ACPA require external diodes for basic inverting operation?

No, the TC7662ACPA does not require external diodes for standard inverting operation (Figure 4-1). Its integrated CMOS switch array replaces discrete diodes, reducing component count, forward voltage loss, and board area. External diodes are only needed in specialized configurations such as positive voltage doubling (Figure 4-6) or cascaded topologies where polarity control is required beyond the native inverter function.

How does the OSC pin on the TC7662ACPA affect performance?

The OSC pin (Pin 7) controls the internal oscillator frequency: connecting an external capacitor to GND lowers the frequency (e.g., 100pF reduces 12kHz to ~2kHz). This reduces switching losses at light loads, improving power efficiency-but requires proportionally larger CP and CR capacitors to maintain low output impedance and ripple. The relationship is documented in DS21468B Figure 4-5 and Oscillator Frequency vs. COSC graph.

What is the output source resistance specification for the TC7662ACPA?

The TC7662ACPA has a typical output source resistance (RO) of 40Ω at IL = 20mA and VDD = 15V, with a maximum of 100Ω under worst-case conditions. This value represents the effective series impedance of the inverted rail and directly impacts load regulation and ripple suppression. RO varies with temperature, input voltage, and capacitor ESR-detailed in DS21468B Section 1.0 Electrical Characteristics and Output Resistance vs. Temperature graph.