Texas Instruments TL7660IDGKT

Overview

TL7660IDGKT from Texas Instruments is a CMOS switched-capacitor voltage converter that generates a regulated negative output voltage (–V_CC) from a positive input supply (1.5 V to 10 V), requiring only two external noncritical capacitors. It operates as a negative voltage converter or voltage doubler, features an internal 10 kHz RC oscillator (adjustable via OSC pin), supports –40°C to 125°C operation, and delivers up to 99.9% open-circuit voltage conversion efficiency - used in portable instrumentation and low-power analog signal chains.

For engineers reviewing the TL7660IDGKT datasheet, TL7660IDGKT pinout, TL7660IDGKT application, or TL7660IDGKT equivalent, key selection considerations include its LV pin logic for low-voltage bypass, output source resistance (120 Ω max at 125°C/10 mA), oscillator frequency tuning capability, latchup protection architecture, and VSSOP-8 package thermal performance (θ_JA = 172°C/W).

Technical Context

The TL7660IDGKT integrates four power MOS switches (one p-channel, three n-channel), an RC oscillator, a voltage-level translator, and a linear regulator with dynamic substrate bias control to prevent latchup across temperature and load conditions. Its anti-latchup logic network continuously monitors V_OUT and adjusts switch substrates to maintain reverse bias on S3/S4 sources.

Oscillator frequency defaults to ~10 kHz at V_CC = 5 V but is scalable downward via external capacitor on OSC pin or upward via external TTL/CMOS clock (with 1 kΩ series resistor). The LV pin must be tied to GND below 3.5 V to disable the internal regulator and avoid excessive dropout; above 3.5 V, it must remain floating to ensure safe operation.

Key Specifications

Pinout & Package

VSSOP-8 (DGK) package: 3.0 mm × 3.0 mm body, 0.65 mm pitch, exposed thermal pad (not electrically connected), moisture sensitivity level 1, RoHS-compliant NiPdAu finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX1044CSA+ and ICL7660SIPAZ, TL7660IDGKT offers the only combination of VSSOP-8 packaging, –40°C to 125°C qualification, LV-controlled low-voltage bypass, and adjustable oscillator - making it uniquely suited for modern automotive and industrial SMT designs demanding extended temperature reliability and flexible biasing.

Availability

TL7660IDGKT is available at Aetrix Electronics and suitable for portable instrumentation, automotive sensor modules, and industrial data loggers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for TL7660IDGKT 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and connectivity technologies, with decades of expertise in power management ICs and high-reliability industrial components.

The TL7660 product line delivers integrated switched-capacitor voltage conversion for space- and cost-sensitive applications where inductorless negative or doubled supplies are essential - targeting portable, medical, and automotive systems.

FAQ

What is the maximum allowable supply voltage for TL7660IDGKT?

The absolute maximum supply voltage (V_CC) for TL7660IDGKT is 10.5 V. Operation beyond this risks permanent damage. The recommended operating range is 1.5 V to 10 V. Exceeding 10 V - even briefly - may trigger destructive latchup or oxide breakdown. Always verify input rail stability and transient margins before deploying TL7660IDGKT in production systems.

How does the LV pin affect TL7660IDGKT performance below 3.5 V?

When V_CC is below 3.5 V, the LV pin must be tied to GND to disable the internal linear regulator. This bypass reduces dropout voltage and quiescent current, enabling stable operation down to 1.5 V. Leaving LV floating under low-voltage conditions causes excessive regulator dropout and possible failure to start. TL7660IDGKT's LV logic is integral to its wide-input-range capability.

Can TL7660IDGKT generate positive voltage doubling?

Yes, TL7660IDGKT can be configured as a positive voltage doubler using two external diodes and two capacitors, delivering up to (2×V_CC) – 2V_F. This mode requires careful diode selection (low V_F, fast recovery) and is less efficient than negative conversion due to diode losses. The TL7660IDGKT datasheet provides Figure 9 as a validated reference schematic for this configuration.

What is the purpose of the NC pin (Pin 1) on TL7660IDGKT?

Pin 1 of TL7660IDGKT is designated NC (No internal connection). It has no electrical function and must remain unconnected - neither grounded nor routed. TI confirms no internal bond wire or circuit node connects to this pin. Routing or loading Pin 1 may introduce parasitic coupling or mechanical stress without benefit, so standard practice is to omit any trace or pad connection.

How does temperature affect TL7660IDGKT's oscillator frequency?

TL7660IDGKT's oscillator frequency varies with temperature: at V_CC = 5 V, it ranges from ~3 kHz at –40°C to ~11 kHz at 125°C (no external capacitor). This drift is inherent to the RC oscillator topology. For stable timing-critical applications, use the OSC pin to inject an external clock or add a temperature-stable capacitor to reduce variation - TL7660IDGKT's datasheet characterizes this behavior in Figure 5.