ST STM6904 User Manual

Features

■ Quad voltage monitoring

■ Accurate ±1.8% across temperature voltage

threshold (±1% at 25 °C)

■ Primary supply (V

programmed) reset thresholds: 3.078
to 2.188 V

■ Second fixed (V2IN) monitor. Fixed (factory-

programmed) reset thresholds: 2.333
to 1.110 V

■ Two additional adjustable supply monitor

inputs (externally adjustable)

■ 0.6 V internal reference

■ RST output (open drain)

■ Output guaranteed for V

■ Reset delay time (t

■ Manual reset input (MR)

■ Low supply current of 12 µA (typ)

■ Power supply voltage 0.8 to 5.5 V

■ RoHS compliant (green package)

■ 8-pin MSOP/TSSOP

■ Operating temperature: –40 to 85 °C (industrial

grade)

Table 1. Device summary

) monitor. Fixed (factory -

CC

≥ 0.8 V

CC

) pin selectable

REC

(1)

STM6904

Quad, ultralow voltage supervisor

with push-button reset

MSOP8

(TSSOP8) (DS)

Applications

■ Set-top boxes

■ Multi-voltage systems

■ Cable/satellite applications

■ Computer systems

■ Data storage equipment

Order code V

(V) V

RST1

(V) t

RST2

(ms) Package

REC

STM6904TZEDS6F 3.078 2.333 210 MSOP8(TSSOP8)

STM6904TWEDS6F 3.078 1.683 210 MSOP8(TSSOP8)

STM6904TGEDS6F 3.078 1.110 210 MSOP8(TSSOP8)

STM6904SYEDS6F 2.955 2.188 210 MSOP8(TSSOP8)

STM6904SFEDS6F 2.955 1.050 210 MSOP8(TSSOP8)

STM6904PWEDS6F 2.866 1.683 210 MSOP8(TSSOP8)

1. Other reset threshold voltages and t
ST sales office for availability.

timeout periods are offered. Minimum order quantities may apply. Contact local

REC

December 2011 Doc ID 14289 Rev 3 1/20

www.st.com

1

Contents STM6904

Contents

1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

2 Pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.1 Push-button reset input (MR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.2 V

2.3 V2IN second fixed voltage monitoring input . . . . . . . . . . . . . . . . . . . . . . . . 7

2.4 V

2.5 V3IN and V4IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

2.6 RST

2.7 TR

primary supply voltage monitoring input . . . . . . . . . . . . . . . . . . . . . . . 7

CC

SS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

active-low, open drain reset output . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

SEL

3 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.1 Setting the adjustable voltage levels for V3IN and V4IN inputs . . . . . . . . . 9

3.2 Power on reset (t

) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

REC

4 Voltage monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

5 Maximum rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

6 DC and AC parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

7 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

8 Part numbering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

9 Package marking information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

10 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2/20 Doc ID 14289 Rev 3

STM6904 List of tables

List of tables

Table 1. Device summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Table 2. Signal names and functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Table 3. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Table 4. DC and AC characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Table 5. TSSOP 8-lead package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Table 6. Ordering information scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Table 7. Marking description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Table 8. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Doc ID 14289 Rev 3 3/20

List of figures STM6904

List of figures

Figure 1. Logic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 2. MSOP/TSSOP-8 connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Figure 3. Functional block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 4. Typical hardware hookup application diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Figure 5. MR

Figure 6. Voltage monitoring diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Figure 7. TSSOP8, 3 x 3mm, package mechanical outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

timing waveforms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4/20 Doc ID 14289 Rev 3

STM6904 Description

1 Description

The STM6904 supervisor is a low voltage/low supply current processor supervisor,
designed to monitor up to four system power supply voltages. This device is targeted at
applications such as “Set-Top Boxes” (STBs), portable, battery-powered systems,
networking and communication systems.

The device supports a push-button type manual reset input (MR
monitors (V
(V

RST1

and V

and V2IN) have fixed (customer-selectable, factory-trimmed) thresholds

CC

). The other two voltage monitor inputs (V3IN and V4IN) are monitored

RST2

). Two of the four supply

using externally adjustable threshold (0.600 V internal reference) to meet specific level
requirements.

If any of the four monitored voltages drops below its factory-trimmed or adjustable
thresholds, or if the MR
low). Once asserted, RST is maintained low for a minimum delay period (t

is asserted to logic low, the reset output RST is asserted (driven

) after ALL

REC

monitored supplies rise above their respective thresholds and MR returns to high. This
device is in the correct reset output logic state when V

greater than 0.8 V.

CC

The STM6904 is available in a standard 8-lead MSOP (TSSOP) package.

Figure 1. Logic diagram

V

CC

V2IN
V3IN
V4IN

TR

MR

SEL

STM6904

V

SS

RST

ai13976

Figure 2. MSOP/TSSOP-8 connections

MR

V

CC

V2IN

V

SS

Doc ID 14289 Rev 3 5/20

1

2

3

4

RST

8

TR

7

6

5

SEL

V4IN

V3IN

ai13977

Description STM6904

Table 2. Signal names and functions

Pin Name Type Function

1MR

2V

CC

Input Active-low manual reset input with internal pull-up resistor

Supply

Primary supply voltage input and integrated fixed threshold under­voltage monitor

3 V2IN Input Second fixed threshold input monitor

4V

SS

Supply Ground

5 V3IN Input Adjustable third reset comparator input

6 V4IN Input Adjustable fourth reset comparator input

7TR

SEL

8RST

Controls selectable t

Input

If pin is tied high (V
If pin is tied low (V
Note: Pin must be tied to V

Output Active-low open drain reset output (10 kΩ internal pull-up)

SS

CC

REC

), t

), t

. Two t

REC

= 420 ms

REC

= 210 ms

REC

or VSS (do not float)

CC

options available.

6/20 Doc ID 14289 Rev 3