Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsPMICsPMIC - ELCs Low side TSSOP 20

AVAILABLE

Functional Diagrams

Pin Configurations appear at end of data sheet.

Functional Diagrams continued at end of data sheet.

UCSP is a trademark of Maxim Integrated Products, Inc.

For pricing, delivery, and

ordering information, please contact Maxim Direct

at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.

General Description

The MAX4820/MAX4821 8-channel relay drivers offer

built-in kickback protection and drive +3.3V/+5V non-

latching or dual-coil-latching relays. These devices are

especially useful when driving +3V relays. Each inde-

pendent open-drain output features a 2Ω on-resistance

and is guaranteed to sink 70mA (min) of load current.

Both devices consume less than 50µA (max) quiescent

current and have 1µA output off-leakage current.

The MAX4820 features an SPI™-/QSPI™-/MICROWIRE™-

compatible serial interface. Input data is shifted into an 8-

bit shift register and latched to the outputs when CS

transitions from low to high. Each data bit in the shift reg-

ister corresponds to a specific output, allowing indepen-

dent control of all outputs.

The MAX4821 features a 4-bit (A0, A1, A2, LVL) paral-

lel-input interface. The first three bits (A0, A1, A2) deter-

mine the output address, and the fourth bit (LVL)

determines whether the selected output is switched on

or off. Data is latched to the outputs when CS transi-

tions from low to high.

Both devices feature separate set and reset functions

that allow the user to turn on or turn off all outputs simul-

taneously with a single control line. Built-in hysteresis

(Schmidt trigger) on all digital inputs allows this device

to be used with slow rising and falling signals, such as

those from optocouplers or RC power-up initialization

circuits. The MAX4820/MAX4821 are available in 20-pin

TSSOP and space-saving 20-pin Thin QFN packages.

Applications

Central Office

ATE

DSL, ADSL Line Cards

Industrial Equipment

E1/T1 Redundancy

Features

♦ 8 Independent Output Channels

♦ Built-In Inductive Kickback Protection

♦ Drive +3V and +5V Relays

♦ Guaranteed 70mA (min) Coil Drive Current

♦ SET Function to Turn On All Outputs

Simultaneously

♦ RESET Function to Turn Off All Outputs

Simultaneously

♦ SPI-/QSPI-/MICROWIRE-Compatible Serial

Interface (MAX4820)

♦ Serial Digital Output for Daisy Chaining

(MAX4820)

♦ Parallel Interface (MAX4821)

♦ Low 50µA (max) Quiescent Supply Current

♦ Space-Saving 20-Pin Thin QFN Package

TOP VIEW

*CONNECT EP TO GND.

*EP

SET

OUT1

OUT2

16 PGND

OUT5

COM

OUT4

OUT3

OUT6

SCLK

DIN

5DOUT

N.C.

GND

OUT8

OUT7

10PGND

MAX4820

THIN QFN

RESET

Pin Configurations

Ordering Information

19-2751; Rev 2; 1/10

Denotes a lead(Pb)-free/RoHS-compliant package.

EP = Exposed pad.

Pin Configurations continued at end of data sheet.

Typical Application Circuits and Functional Diagrams

appear at end of data sheet.

SPI and QSPI are trademarks of Motorola, Inc.

MICROWIRE is a trademark of National Semiconductor Corp.

PART TEMP RANGE PIN-PACKAGE

MAX4820ETP+ -40°C to +85°C 20 Thin QFN-EP*

MAX4820EUP+ -40°C to +85°C 20 TSSOP-EP*

MAX4821ETP+ -40°C to +85°C 20 Thin QFN-EP*

MAX4821EUP+ -40°C to +85°C 20 TSSOP-EP*

MAX4820/MAX4821

Ordering Information

+3.3V/+5V, 8-Channel, Cascadable Relay Drivers

with Serial/Parallel Interface

Summary of content (12 pages)

PAGE 1
MAX4820/MAX4821 LE AVAILAB +3.
PAGE 2
MAX4820/MAX4821 +3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) VCC, COM..............................................................-0.3V to +6.0V OUT_........................................................-0.3V to (VCOM + 0.3V) CS, SCLK, DIN, SET, RESET, A0, A1, A2, LVL......-0.3V to +6.0V DOUT..........................................................-0.3V to (VCC + 0.
PAGE 3
MAX4820/MAX4821 3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface ELECTRICAL CHARACTERISTICS (continued) (VCC = +3V to +5.5V, VCOM = VCC, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS SPI TIMING (MAX4820) Turn-On Time (OUT_) tON From rising edge of CS, RL = 50Ω, CL = 50pF 1.0 µs Turn-Off Time (OUT_) tOFF From rising edge of CS, RL = 50Ω, CL = 50pF 1.0 µs 2.
PAGE 4
MAX4820/MAX4821 +3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface Typical Operating Characteristics (VCOM = VCC, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) 20 SUPPLY CURRENT (μA) 20 15 10 VCC = 5.5V VCC = 5V 15 10 VCC = 3.3V VCC = 2.3V 5 5 0 0 1000 ALL LOGIC INPUTS CONNECTED 900 800 SUPPLY CURRENT (μA) ALL LOGIC INPUTS = 0 MAX4820 toc02 25 MAX4820 toc01 25 SUPPLY CURRENT (μA) SUPPLY CURRENT vs.
PAGE 5
MAX4820/MAX4821 3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface Typical Operating Characteristics (continued) (VCOM = VCC, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) INPUT LOGIC THRESHOLD BACK EMF CLAMPING vs. SUPPLY VOLTAGE WITH STANDARD 3V RELAY MAX4820 toc11 MAX4820 toc10 2.50 INPUT LOGIC THRESHOLD (V) 2.25 2.00 VCS 5V/div 0 1.75 1.50 1.25 OUT_ 1V/div 1.00 0 0.75 OUT_ TURNS OFF VCC = 3.3V 0.50 2.3 2.7 3.1 3.5 3.9 4.3 4.
PAGE 6
MAX4820/MAX4821 +3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface Pin Description (continued) PIN MAX4820 MAX4821 NAME FUNCTION THIN QFN TSSOP THIN QFN TSSOP 12 14 12 14 OUT5 Open-Drain Output 5. Connect OUT5 to the low side of a relay coil. This output is pulled to PGND when activated, but otherwise is high impedance. 13 15 13 15 COM Common Free-Wheeling Diodes. Connect COM to VCC. COM can also be connected to a separate supply that is higher than VCC.
PAGE 7
MAX4820/MAX4821 3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface CS tCSW tCL tCSS tCSO tCSH tCH SCLK tDH tDS DIN D6 D7 D0 D1 tDO DOUT tON, tOFF OUT_ Figure 1. 3-Wire Serial-Interface Timing Diagram (MAX4820 only) Table 1.
PAGE 8
MAX4820/MAX4821 +3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface Table 2.
PAGE 9
MAX4820/MAX4821 3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface is shifted through all the MAX4820s in series. When CS goes high, all outputs update simultaneously. The MAX4820 can also be used in a slave configuration that allows the user to address individual devices. Connect all the DIN pins together, and use the CS input to address one device at a time. Drive CS low to select a slave and input the data into the shift register.
PAGE 10
MAX4820/MAX4821 +3.
PAGE 11
MAX4820/MAX4821 3.
PAGE 12
MAX4820/MAX4821 +3.3V/+5V, 8-Channel, Cascadable Relay Drivers with Serial/Parallel Interface Revision History REVISION NUMBER REVISION DATE 0 1/03 Initial release. 1 4/09 Corrected error in the Electrical Characteristics table. 2 1/10 Added exposed pad to TSSOP package in the Ordering Information, Pin Description, and Pin Configurations. DESCRIPTION PAGES CHANGED — Added Reflow Temperature to the Absolute Maximum Ratings section.