전원 관리 AC/DC 및 DC/DC 컨트롤러(외장 FET)

TL497A

활성

500mA 피크 스텝업, 스텝다운, 인버팅 스위칭 전압 레귤레이터

이 제품의 최신 버전이 있습니다

open-in-new 대안 비교
다른 핀 출력을 지원하지만 비교 대상 장치와 동일한 기능
LM5157 활성 6A/4A, 50V, 2.2MHz 와이드 VIN 부스트, 플라이백 및 SEPIC 컨버터, 듀얼 랜덤 확산 스펙트럼 지원 Lower quiescent current, wider voltage range

제품 상세 정보

Vin (min) (V) 4.5 Vin (max) (V) 12 Operating temperature range (°C) -40 to 85 Topology Boost, Buck, Flyback, Forward, SEPIC Rating Catalog Vout (min) (V) -25 Vout (max) (V) 30 Features Enable, Nonsynchronous rectification Iq (typ) (µA) 11000
Vin (min) (V) 4.5 Vin (max) (V) 12 Operating temperature range (°C) -40 to 85 Topology Boost, Buck, Flyback, Forward, SEPIC Rating Catalog Vout (min) (V) -25 Vout (max) (V) 30 Features Enable, Nonsynchronous rectification Iq (typ) (µA) 11000
PDIP (N) 14 181.42 mm² 19.3 x 9.4 SOIC (D) 14 51.9 mm² 8.65 x 6 SOP (NS) 14 79.56 mm² 10.2 x 7.8 TSSOP (PW) 14 32 mm² 5 x 6.4
  • High Efficiency . . . 60% or Greater
  • Peak Switch Current . . . 500 mA
  • Input Current Limit Protection
  • TTL-Compatible Inhibit
  • Adjustable Output Voltage
  • Input Regulation . . . 0.2% Typ
  • Output Regulation . . . 0.4% Typ
  • Soft Start-Up Capability
  • Can be Used in Buck, Boost, and Inverting Configurations

  • High Efficiency . . . 60% or Greater
  • Peak Switch Current . . . 500 mA
  • Input Current Limit Protection
  • TTL-Compatible Inhibit
  • Adjustable Output Voltage
  • Input Regulation . . . 0.2% Typ
  • Output Regulation . . . 0.4% Typ
  • Soft Start-Up Capability
  • Can be Used in Buck, Boost, and Inverting Configurations

The TL497A incorporates all the active functions required in the construction of switching voltage regulators. It also can be used as the control element to drive external components for high-power-output applications. The TL497A was designed for ease of use in step-up, step-down, or voltage-inversion applications requiring high efficiency.

The TL497A is a fixed-on-time variable-frequency switching-voltage-regulator control circuit. The switch-on time is programmed by a single external capacitor connected between FREQ CONTROL and GND. This capacitor, CT, is charged by an internal constant-current generator to a predetermined threshold. The charging current and the threshold vary proportionally with VCC. Thus, the switch-on time remains constant over the specified range of input voltage (4.5 V to 12 V). Typical on times for various values of CT are as follows:

TIMING CAPACITOR, CT (pF) 200 250 350 400 500 750 1000 1500 2000
ON TIME (µs) 19 22 26 32 44 56 80 120 180

The output voltage is controlled by an external resistor ladder network (R1 and R2 in Figures 1, 2, and 3) that provides a feedback voltage to the comparator input. This feedback voltage is compared to the reference voltage of 1.2 V (relative to SUBSTRATE) by the high-gain comparator. When the output voltage decays below the value required to maintain 1.2 V at the comparator input, the comparator enables the oscillator circuit, which charges and discharges CT as described above. The internal pass transistor is driven on during the charging of CT. The internal transistor can be used directly for switching currents up to 500 mA. Its collector and emitter are uncommitted, and it is current driven to allow operation from the positive supply voltage or ground. An internal Schottky diode matched to the current characteristics of the internal transistor also is available for blocking or commutating purposes. The TL497A also has on-chip current-limit circuitry that senses the peak currents in the switching regulator and protects the inductor against saturation and the pass transistor against overstress. The current limit is adjustable and is programmed by a single sense resistor, RCL, connected between VCC and CUR LIM SENS. The current-limit circuitry is activated when 0.7 V is developed across RCL. External gating is provided by the INHIBIT input. When the INHIBIT input is high, the output is turned off.

Simplicity of design is a primary feature of the TL497A. With only six external components (three resistors, two capacitors, and one inductor), the TL497A operates in numerous voltage-conversion applications (step-up, step-down, invert) with as much as 85% of the source power delivered to the load. The TL497A replaces the TL497 in all applications.

The TL497AC is characterized for operation from 0°C to 70°C. The TL497AI is characterized for operation from -40°C to 85°C.

The TL497A incorporates all the active functions required in the construction of switching voltage regulators. It also can be used as the control element to drive external components for high-power-output applications. The TL497A was designed for ease of use in step-up, step-down, or voltage-inversion applications requiring high efficiency.

The TL497A is a fixed-on-time variable-frequency switching-voltage-regulator control circuit. The switch-on time is programmed by a single external capacitor connected between FREQ CONTROL and GND. This capacitor, CT, is charged by an internal constant-current generator to a predetermined threshold. The charging current and the threshold vary proportionally with VCC. Thus, the switch-on time remains constant over the specified range of input voltage (4.5 V to 12 V). Typical on times for various values of CT are as follows:

TIMING CAPACITOR, CT (pF) 200 250 350 400 500 750 1000 1500 2000
ON TIME (µs) 19 22 26 32 44 56 80 120 180

The output voltage is controlled by an external resistor ladder network (R1 and R2 in Figures 1, 2, and 3) that provides a feedback voltage to the comparator input. This feedback voltage is compared to the reference voltage of 1.2 V (relative to SUBSTRATE) by the high-gain comparator. When the output voltage decays below the value required to maintain 1.2 V at the comparator input, the comparator enables the oscillator circuit, which charges and discharges CT as described above. The internal pass transistor is driven on during the charging of CT. The internal transistor can be used directly for switching currents up to 500 mA. Its collector and emitter are uncommitted, and it is current driven to allow operation from the positive supply voltage or ground. An internal Schottky diode matched to the current characteristics of the internal transistor also is available for blocking or commutating purposes. The TL497A also has on-chip current-limit circuitry that senses the peak currents in the switching regulator and protects the inductor against saturation and the pass transistor against overstress. The current limit is adjustable and is programmed by a single sense resistor, RCL, connected between VCC and CUR LIM SENS. The current-limit circuitry is activated when 0.7 V is developed across RCL. External gating is provided by the INHIBIT input. When the INHIBIT input is high, the output is turned off.

Simplicity of design is a primary feature of the TL497A. With only six external components (three resistors, two capacitors, and one inductor), the TL497A operates in numerous voltage-conversion applications (step-up, step-down, invert) with as much as 85% of the source power delivered to the load. The TL497A replaces the TL497 in all applications.

The TL497AC is characterized for operation from 0°C to 70°C. The TL497AI is characterized for operation from -40°C to 85°C.

다운로드 스크립트와 함께 비디오 보기 동영상

기술 자료

star =TI에서 선정한 이 제품의 인기 문서
검색된 결과가 없습니다. 검색어를 지우고 다시 시도하십시오.
6개 모두 보기
유형 직함 날짜
* Data sheet TL497A datasheet (Rev. F) 2005/02/22
Application note Understanding Inverting Buck-Boost Power Stages in Switch Mode Power Supplies (Rev. B) 2019/03/12
Selection guide Power Management Guide 2018 (Rev. R) 2018/06/25
Application note Designing Switching Voltage Regulators with TL497A 2003/08/11
Application note Understanding Boost Power Stages In Switchmode Power Supplies 1999/03/04
Application note Understanding Buck Power Stages In Switchmode Power Supplies 1999/03/04

설계 및 개발

추가 조건 또는 필수 리소스는 사용 가능한 경우 아래 제목을 클릭하여 세부 정보 페이지를 확인하세요.

패키지 CAD 기호, 풋프린트 및 3D 모델
PDIP (N) 14 Ultra Librarian
SOIC (D) 14 Ultra Librarian
SOP (NS) 14 Ultra Librarian
TSSOP (PW) 14 Ultra Librarian

주문 및 품질

포함된 정보:
  • RoHS
  • REACH
  • 디바이스 마킹
  • 납 마감/볼 재질
  • MSL 등급/피크 리플로우
  • MTBF/FIT 예측
  • 물질 성분
  • 인증 요약
  • 지속적인 신뢰성 모니터링
포함된 정보:
  • 팹 위치
  • 조립 위치

지원 및 교육

TI 엔지니어의 기술 지원을 받을 수 있는 TI E2E™ 포럼

콘텐츠는 TI 및 커뮤니티 기고자에 의해 "있는 그대로" 제공되며 TI의 사양으로 간주되지 않습니다. 사용 약관을 참조하십시오.

품질, 패키징, TI에서 주문하는 데 대한 질문이 있다면 TI 지원을 방문하세요. ​​​​​​​​​​​​​​

동영상