Keithley 487, 486 Datasheet

486 and 487 Picoammeters

AMMETER ANALOG OUTPUT

ACCURACY (1 Year)* (10%–90%)

RANGE RESOLUTION ±(%rdg + offset) OFF ON

2 nA 10 fA 0.3 + 500 fA 12 ms 70 ms

20 nA 100 fA 0.2 + 3 pA 4 ms 17 ms

200 nA 1 pA 0.15 + 20 pA 800 µs 4 ms

2 µA 10 pA 0.15 + 200 pA 380 µs 2 ms

20 µA 100 pA 0.1 + 2 nA 160 µs 370 µs

200 µA 1 nA 0.1 + 20 nA 160 µs 370 µs

2 mA 10 nA 0.1 + 200 nA 160 µs 370 µs

* When properly zeroed.

MAXIMUM OVERLOAD: 350V peak on nA ranges and 2µA range; 50V peak on 20µA, 200µA, and

2mA ranges. Higher voltage sources must be current limited at 3mA.

INPUT VOLTAGE BURDEN: <200µV (18°–28°C) for inputs <100µA; <2mV for 2mA input; 20µV/°C

temperature coefficient.

TEMPERATURE COEFFICIENT (0°–18°C & 28°–50°C): ±(0.15 ×applicable accuracy specification)/ °C. NMRR: >60dB at 50Hz (LINE 50Hz integration) or 60Hz (LINE 60Hz integration). ANALOG OUTPUT:

Range: ±2V for full range input (non-inverting). Accuracy: ±(2.5% + 3mV ); resistive loads >2kΩ; 18°–28°C. Impedance: <100Ω, DC–2kHz.

RANGING: Automatic or manual. AUTORANGING TIME: <200ms to final range (analog filter OFF).

MAXIMUM READING RATES (readings/second):

INTEGRATION INTO INTO IEEE-488

SETTING RESOLUTION DATA STORE DATA STORE BUS**

FAST 41⁄2-Digit 100 180 16 LINE 60Hz 5 LINE 50Hz 51⁄2-Digit 33 38 12

** One-shot on TALK, G7 data format.

⁄2-Digit 40 44 14

18°–28°C Analog Filter

CONTINUOUS TRIGGERED VIA

Rise Time

EXTERNAL TRIGGERED

VOLTAGE SOURCE (487 only):

RANGE STEP (1 Year) NOISE COEFFICIENT

(maximum SIZE 18°–28°C (p-p)*** 0°–18°C &

value) (typical) ±(%setting + offset) 0.1–10Hz 28°–50°C

±505.00 V 10 mV 0.15 + 40 mV <1.5 mV 80 ppm + 2 mV/°C ±50.500 V 1 mV 0.1 + 4 mV <150 µV 50 ppm + 200µV/°C

*** With LO terminal connected to chassis.

SELECTABLE CURRENT LIMIT: 2.5mA ±0.5mA or 25µA ±5µA.

WIDEBAND NOISE: <60/400mV p-p ±50/±500V range, 0.1Hz to 20MHz.

TIME STABILITY: ±(0.003% + 1mV ) over 24 hours at constant temperature. OUTPUT RESISTANCE: <2.5Ω.

ACCURACY TEMPERATURE

V/I OHMS (487 only)

Used with voltage source; resistance calculated from voltage setting and measured current. V/I OHMS accuracy equals voltage source accuracy plus ammeter accuracy. Typical accuracy better than 0.6% for readings between 1kΩ and 1TΩ.

IEEE-488 BUS IMPLEMENTATION

MULTILINE COMMANDS: DCL, SDC, GET, GTL, UNT, UNL, SPE,

SPD.

UNILINE COMMANDS: IFC, REN, EOI, SRQ, ATN.

INTERFACE FUNCTIONS: SH1, AH1, T5, TE0, L4, LE0, SR1, RL1, PP0,

DC1, DT1, C0, E1.

PROGRAMMABLE PARAMETERS: All parameters programmable

except for IEEE-488 bus address and frequency for line integration.

TRIGGER TO FIRST BYTE: <50ms (trigger on TALK, ATN false to talk-

er DAV true, G7 data format).

GENERAL

DATA STORE and MIN/MAX: Stores up to 512 readings and identifies

minimum and maximum reading.

PROGRAMMABLE READING INTERVAL: 10ms to 999.999s in 1ms

increments.

TRIGGER: One-shot or continuous from front panel, IEEE-488 bus,

and rear panel BNC.

PROGRAMMABLE TRIGGER DELAY: 1ms to 999.999s in 1ms incre-

ments.

DISPLAY: One ten character plus one eight character alphanumeric

LED displays with normal/dim/off intensity control.

MAXIMUM VOLTAGE BETWEEN VOLTAGE SOURCE AND CURRENT

METER: 500V DC.

MAXIMUM VOLTAGE BETWEEN CHASSIS AND VOLTAGE SOURCE

OR CURRENT METER: 500V DC.

REAR PANEL CONNECTORS:

Input Connector: 3-lug triax.

Analog Output: 5-way binding post.

External Trigger and Meter Complete: BNC connectors.

IEEE-488 Connector: Chassis grounded.

Voltage Source Output (487 only): 5-way binding post.

Interlock Connector (487 only): 3-pin miniature DIN.

EMC: Conforms to European Union Directive 89/336/EEC.

SAFETY: Conforms to European Union Directive 73/23/EEC (meets

EN61010-1/IEC 1010).

ENVIRONMENT:

Operating: 0°–50°C, <70% RH up to 35°C; linearly derate 3% RH/°C,

up to 50°C.

Storage: –25° to 60°C.

WARM-UP: 2 hours to rated accuracy.

POWER: 105–125V AC or 210–250V AC (external switch selectable),

90–110V and 180–220V AC version available. 50Hz or 60Hz, 45VA maximum.

DIMENSIONS, WEIGHT: 90mm high × 213mm wide × 397mm deep

⁄

in × 8

ACCESSORIES SUPPLIED:

Instruction Manual Quick Reference Guide Model 236-ILC-3 (487 only): Interlock Cable Model 7078-ALG: 3-slot Triax to Alligator Clip Cable

⁄

in × 15

⁄8in). Net weight 4.25kg (9.3 lb).

2/23/01

Rev. P