Datasheet

ManualsBrandsLINEAR TECHNOLOGY ManualsPMICsPMIC - voltage reference Shunt Adjustable SOIC 8

LT1634

1634fb

DESCRIPTIO

FEATURES

APPLICATIO S

TYPICAL APPLICATIO

Micropower Precision

Shunt Voltage Reference

■

Initial Voltage Accuracy: 0.05%

■

Low Operating Current: 10

■

Low Drift: 10ppm/

C Max

■

Less Than 1Ω Dynamic Impedance

■

Available in 1.25V, 2.5V, 4.096V and 5V in SO-8

and TO-92 Packages

■

1.25V and 2.5V Available in MSOP Package

■

Both Commercial and Industrial Temperature Range

Parts Are Available

The LT

1634 is a micropower, precision, shunt voltage

reference. The bandgap reference uses trimmed precision

thin film resistors to achieve 0.05% initial voltage accu-

racy. Improved curvature correction technique guaran-

tees 10ppm/°C maximum temperature drift. Advances in

design, processing and packaging techniques guarantee

10µA operation and low temperature cycling hysteresis.

The LT1634 does not require an output compensation

capacitor, but is stable with capacitive loads. Low dynamic

impedance makes the LT1634 reference easy to use from

unregulated supplies.

The LT1634 reference can be used as a high performance

upgrade to the LM185/LM385, LT1004 and LT1034

where lower power and guaranteed temperature drift is

required.

, LTC and LT are registered trademarks of Linear Technology Corporation.

–

LT1495

–5V

LT1634-4.096

= 200µA

OUTPUT ACCURACY

BETTER THAN 0.075%

AT ±500µA OUTPUT

LTC

1043

–5V

1634 TA01

1µF

45k

OUT

4.096V

–

LT1495

OUT

–4.096V

Super Accurate ±4.096V Output References

Temperature Drift

TEMPERATURE (°C)

–40

REVERSE VOLTAGE CHANGE (mV)

1.5

1634 TA02

–1.0

–20 20

–1.5

–2.0

2.0

1.0

0.5

–0.5

40 60 80 100

= 10µA

OUT

= 1.25V

■

Portable Meters

■

Precision Regulators

■

A/D and D/A Converters

■

Calibrators

Summary of content (12 pages)

PAGE 1
LT1634 Micropower Precision Shunt Voltage Reference U FEATURES ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO Initial Voltage Accuracy: 0.05% Low Operating Current: 10µA Low Drift: 10ppm/°C Max Less Than 1Ω Dynamic Impedance Available in 1.25V, 2.5V, 4.096V and 5V in SO-8 and TO-92 Packages 1.25V and 2.5V Available in MSOP Package Both Commercial and Industrial Temperature Range Parts Are Available The LT ®1634 is a micropower, precision, shunt voltage reference.
PAGE 2
LT1634 W W U W ABSOLUTE MAXIMUM RATINGS (Note 1) Operating Current 1.25V ............................................................. 100mA 2.5V ................................................................. 50mA 4.096V, 5V ....................................................... 30mA Forward Current .................................................. 20mA Operating Temperature Range Commercial ............................................. 0°C to 70°C Industrial .....................................
PAGE 3
LT1634 U AVAILABLE OPTIO S TEMPERATURE 0°C to 70°C ACCURACY (%) 0.05 TEMPERATURE COEFFICIENT (ppm/°C) 10 – 40°C to 85°C 0.05 10 0°C to 70°C 0.05 25 – 40°C to 85°C 0.05 25 0°C to 70°C 0.20 25 MS8 LT1634BCMS8-1.25 LT1634BCMS8-2.5 PACKAGE TYPE S8 LT1634ACS8-1.25 LT1634ACS8-2.5 LT1634ACS8-4.096 LT1634ACS8-5 LT1634AIS8-1.25 LT1634AIS8-2.5 LT1634AIS8-4.096 LT1634AIS8-5 LT1634BCS8-1.25 LT1634BCS8-2.5 LT1634BCS8-4.096 LT1634BCS8-5 LT1634BIS8-1.25 LT1634BIS8-2.5 LT1634BIS8-4.
PAGE 4
LT1634 2.5V ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C.
PAGE 5
LT1634 4.096V ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. (Note 3) PARAMETER CONDITIONS Temperature Coefficient (Note 8) LT1634A, IR = 20µA LT1634B/LT1634C, IR = 20µA Reverse Dynamic Impedance (Note 5) 20µA ≤ IR ≤ 2mA MIN TYP MAX UNITS ● ● 4 10 10 25 ppm/°C ppm/°C ● 0.15 0.20 0.75 1.50 Ω Ω Low Frequency Noise (Note 6) IR = 20µA, 0.
PAGE 6
LT1634 U W 1.25V TYPICAL PERFOR A CE CHARACTERISTICS 10µA 100µA 200µA 500µA 1mA REVERSE VOLTAGE CHANGE (mV) 1.5 6 4 2 0.8 0.4 1.2 REVERSE VOLTAGE (V) 0 1.0 TA = – 40°C TO 85°C REVERSE VOLTAGE CHANGE (mV) TA = – 40°C TO 85°C 8 0.5 0 – 0.5 –1.0 –1.5 –2.0 – 40 1.6 –20 20 40 0 TEMPERATURE (°C) 60 1 TA = 25°C f = 25Hz Forward Characteristics TA = 25°C DYNAMIC IMPEDANCE (Ω) TA = 25°C 1 0.01 10 0.1 1 REVERSE CURRENT (mA) 100 1.2 10000 10 0.1 1 10 REVERSE CURRENT (mA) 1634-1.
PAGE 7
LT1634 U W 2.5V TYPICAL PERFOR A CE CHARACTERISTICS Reverse Characteristics 6 4 REVERSE VOLTAGE CHANGE (mV) 8 6 4 2 0.5 0 1.5 2.0 1.0 REVERSE VOLTAGE (V) 2.5 3 2 1 0 –1 –2 –3 –4 – 40 0 3.0 TA = – 40°C TO 85°C 10µA 100µA 200µA 500µA 1mA TA = – 40°C TO 85°C REVERSE VOLTAGE CHANGE (mV) 10 –20 20 40 0 TEMPERATURE (°C) 60 Reverse Dynamic Impedance 10 1 0.01 0.1 1 10 REVERSE CURRENT (mA) 100 TA = 25°C IR = 10µA COUT = 0µF 100 IR = 10µA COUT = 0.068µF IR = 100µA COUT = 0.
PAGE 8
LT1634 U W 4.096V TYPICAL PERFOR A CE CHARACTERISTICS 6 5 REVERSE VOLTAGE CHANGE (mV) 16 12 8 4 0 4 2 0 –2 –4 –6 – 40 5 2 3 4 REVERSE VOLTAGE (V) 1 20µA 100µA 200µA 500µA 1mA – 20 0 40 20 TEMPERATURE (°C) 1634-4 G01 3 2 1 DYNAMIC IMPEDANCE (Ω) 0.01 0.1 1 10 REVERSE CURRENT (mA) 100 Forward Characteristics TA = 25°C IR = 20µA COUT = 0µF 1000 100 IR = 20µA COUT = 0.033µF 10 IR = 100µA COUT = 0.33µF IR = 100µA COUT = 0µF 1 0.1 0.01 0.1 1 10 FREQUENCY (kHz) 100 0.8 0.4 0 0.
PAGE 9
LT1634 U W 5V TYPICAL PERFOR A CE CHARACTERISTICS Reverse Characteristics 20 8 5 16 12 8 4 0 2 3 4 REVERSE VOLTAGE (V) 1 5 6 4 2 0 –2 –4 –6 –8 – 40 6 TA = –40°C TO 85°C 20µA 100µA 200µA 500µA 1mA REVERSE VOLTAGE CHANGE (mV) REVERSE VOLTAGE CHANGE (mV) – 20 0 40 20 TEMPERATURE (°C) 60 1634-5 G01 DYNAMIC IMPEDANCE (Ω) DYNAMIC IMPEDANCE (Ω) 1 0.01 0.1 1 10 REVERSE CURRENT (mA) 100 TA = 25°C 1000 IR = 20µA COUT = 0µF 100 10 IR = 100µA COUT = 0µF 1 0.1 0.01 0.
PAGE 10
LT1634 U U W U APPLICATIONS INFORMATION The reverse characteristics of the LT1634 behave like a resistor in parallel with a Zener diode. This simple, well behaved characteristic is important to the proper operation of circuits like Figure 1. The adjustable output voltage reference depends upon positive feedback from the LT1495’s output to start-up and regulate the bias current for the LT1634. VIN ≥ 10.5V – 1.25V V RB = OUT 10µA + VOUT 1.5V TO 10V LT1495 LT1634-1.25 – R1 50k TO 1.
PAGE 11
LT1634 U PACKAGE DESCRIPTION MS8 Package 8-Lead Plastic MSOP (Reference LTC DWG # 05-08-1660) 0.254 (.010) 0.889 ± 0.127 (.035 ± .005) DETAIL “A” 0° – 6° TYP GAUGE PLANE 5.23 (.206) MIN 0.53 ± 0.015 (.021 ± .006) 3.2 – 3.45 (.126 – .136) 1.10 (.043) MAX 3.00 ± 0.102 (.118 ± .004) (NOTE 3) 0.86 (.034) REF 8 0.52 (.206) REF 7 6 5 0.18 (.077) 0.42 ± 0.04 (.0165 ± .0015) TYP SEATING PLANE 0.65 (.0256) BSC DETAIL “A” RECOMMENDED SOLDER PAD LAYOUT NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2.
PAGE 12
LT1634 U TYPICAL APPLICATIONS Single Cell Li-Ion Battery Supervisory Circuit (IQ = 20µA) OFF CHARGER VBAT SW T0 LOAD 1.75V – A2 1/4 LT1496 RS 51k 5% + + A1 1/4 LT1496 R1 500k 0.1% – 1.25V VBAT + A3 1/4 LT1496 RH1 10M 5% D1 RH2 10M 5% D2 A RSW 1M 5% BATTERY – A4 1/4 LT1496 – + R2 1.25M 0.1% LT1634-1.25 R3 1.75M 0.1% R4 1.25M 0.1% 1634 TA05 D1, D2: 1N458 R1 TO R4: CAR6 SERIES IRC (512) 992-7900 Micropower Voltage and Current Reference R3 249k 0.